Vim documentation: eval

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*eval.txt*      For Vim version 7.0.  Last change: 2006 May 06


                  VIM REFERENCE MANUAL    by Bram Moolenaar



Expression evaluation                   *expression* *expr* *E15* *eval*

Using expressions is introduced in chapter 41 of the user manual |usr_41.txt|.

Note: Expression evaluation can be disabled at compile time.  If this has been
done, the features in this document are not available.  See |+eval| and
|no-eval-feature|.

1.  Variables                   |variables|
    1.1 Variable types
    1.2 Function references             |Funcref|
    1.3 Lists                           |Lists|
    1.4 Dictionaries                    |Dictionaries|
    1.5 More about variables            |more-variables|
2.  Expression syntax           |expression-syntax|
3.  Internal variable           |internal-variables|
4.  Builtin Functions           |functions|
5.  Defining functions          |user-functions|
6.  Curly braces names          |curly-braces-names|
7.  Commands                    |expression-commands|
8.  Exception handling          |exception-handling|
9.  Examples                    |eval-examples|
10. No +eval feature           |no-eval-feature|
11. The sandbox                 |eval-sandbox|
12. Textlock                    |textlock|

{Vi does not have any of these commands}

==============================================================================

1. Variables                                            *variables*

1.1 Variable types 

                                                        *E712*
There are five types of variables:

Number          A 32 bit signed number.
                Examples:  -123  0x10  0177

String          A NUL terminated string of 8-bit unsigned characters (bytes).
                Examples: "ab\txx\"--"  'x-z''a,c'

Funcref         A reference to a function |Funcref|.
                Example: function("strlen")

List            An ordered sequence of items |List|.
                Example: [1, 2, ['a', 'b']]

Dictionary    An associative, unordered array: Each entry has a key and a
                value. |Dictionary|
                Example: {'blue': "#0000ff", 'red': "#ff0000"}

The Number and String types are converted automatically, depending on how they
are used.

Conversion from a Number to a String is by making the ASCII representation of
the Number.  Examples:
     Number 123      -->  String "123"
     Number 0        -->  String "0"
     Number -1       -->  String "-1"

Conversion from a String to a Number is done by converting the first digits
to a number.  Hexadecimal "0xf9" and Octal "017" numbers are recognized.  If
the String doesn't start with digits, the result is zero.  Examples:
     String "456"    -->  Number 456
     String "6bar"   -->  Number 6
     String "foo"    -->  Number 0
     String "0xf1"   -->  Number 241
     String "0100"   -->  Number 64
     String "-8"     -->  Number -8
     String "+8"     -->  Number 0

To force conversion from String to Number, add zero to it:
     :echo "0100" + 0
        64 

To avoid a leading zero to cause octal conversion, or for using a different
base, use |str2nr()|.

For boolean operators Numbers are used.  Zero is FALSE, non-zero is TRUE.

Note that in the command
     :if "foo"
"foo" is converted to 0, which means FALSE.  To test for a non-empty string,
use strlen():
     :if strlen("foo")

                                *E745* *E728* *E703* *E729* *E730* *E731*
List, Dictionary and Funcref types are not automatically converted.


                                                                *E706*
You will get an error if you try to change the type of a variable.  You need
to |:unlet| it first to avoid this error.  String and Number are considered
equivalent though.  Consider this sequence of commands:
     :let l = "string"
     :let l = 44             " changes type from String to Number
     :let l = [1, 2, 3]      " error!


1.2 Function references 

                                        *Funcref* *E695* *E718*
A Funcref variable is obtained with the |function()| function.  It can be used
in an expression in the place of a function name, before the parenthesis
around the arguments, to invoke the function it refers to.  Example:

     :let Fn = function("MyFunc")
     :echo Fn()

                                                        *E704* *E705* *E707*
A Funcref variable must start with a capital, "s:", "w:", "t:" or "b:".  You
cannot have both a Funcref variable and a function with the same name.

A special case is defining a function and directly assigning its Funcref to a
Dictionary entry.  Example:
     :function dict.init() dict
     :   let self.val = 0
     :endfunction

The key of the Dictionary can start with a lower case letter.  The actual
function name is not used here.  Also see |numbered-function|.

A Funcref can also be used with the |:call| command:
     :call Fn()
     :call dict.init()

The name of the referenced function can be obtained with |string()|.
     :let func = string(Fn)

You can use |call()| to invoke a Funcref and use a list variable for the
arguments:
     :let r = call(Fn, mylist)


1.3 Lists 

                                                        *List* *Lists* *E686*
A List is an ordered sequence of items.  An item can be of any type.  Items
can be accessed by their index number.  Items can be added and removed at any
position in the sequence.


List creation 

                                                        *E696* *E697*
A List is created with a comma separated list of items in square brackets.
Examples:
     :let mylist = [1, two, 3, "four"]
     :let emptylist = []

An item can be any expression.  Using a List for an item creates a
List of Lists:
     :let nestlist = [[11, 12], [21, 22], [31, 32]]

An extra comma after the last item is ignored.


List index 

                                                        *list-index* *E684*
An item in the List can be accessed by putting the index in square brackets
after the List.  Indexes are zero-based, thus the first item has index zero.
     :let item = mylist[0]           " get the first item: 1
     :let item = mylist[2]           " get the third item: 3

When the resulting item is a list this can be repeated:
     :let item = nestlist[0][1]      " get the first list, second item: 12
 
A negative index is counted from the end.  Index -1 refers to the last item in
the List, -2 to the last but one item, etc.
     :let last = mylist[-1]          " get the last item: "four"

To avoid an error for an invalid index use the |get()| function.  When an item
is not available it returns zero or the default value you specify:
     :echo get(mylist, idx)
     :echo get(mylist, idx, "NONE")


List concatenation 

Two lists can be concatenated with the "+" operator:
     :let longlist = mylist + [5, 6]
     :let mylist += [7, 8]

To prepend or append an item turn the item into a list by putting [] around
it.  To change a list in-place see |list-modification| below.


Sublist 

A part of the List can be obtained by specifying the first and last index,
separated by a colon in square brackets:
     :let shortlist = mylist[2:-1]   " get List [3, "four"]

Omitting the first index is similar to zero.  Omitting the last index is
similar to -1.
        :let endlist = mylist[2:]   " from item 2 to the end: [3, "four"]
        :let shortlist = mylist[2:2]        " List with one item: [3]
        :let otherlist = mylist[:]  " make a copy of the List

If the first index is beyond the last item of the List or the second item is
before the first item, the result is an empty list.  There is no error
message.

If the second index is equal to or greater than the length of the list the
length minus one is used:
     :let mylist = [0, 1, 2, 3]
     :echo mylist[2:8]               " result: [2, 3]

NOTE: mylist[s:e] means using the variable "s:e" as index.  Watch out for
using a single letter variable before the ":".  Insert a space when needed:
mylist[s : e].


List identity 

                                                        *list-identity*
When variable "aa" is a list and you assign it to another variable "bb", both
variables refer to the same list.  Thus changing the list "aa" will also
change "bb":
     :let aa = [1, 2, 3]
     :let bb = aa
     :call add(aa, 4)
     :echo bb
        [1, 2, 3, 4]

Making a copy of a list is done with the |copy()| function.  Using [:] also
works, as explained above.  This creates a shallow copy of the list: Changing
a list item in the list will also change the item in the copied list:
     :let aa = [[1, 'a'], 2, 3]
     :let bb = copy(aa)
     :call add(aa, 4)
     :let aa[0][1] = 'aaa'
     :echo aa
        [[1, aaa], 2, 3, 4]
     :echo bb
        [[1, aaa], 2, 3]

To make a completely independent list use |deepcopy()|.  This also makes a
copy of the values in the list, recursively.  Up to a hundred levels deep.

The operator "is" can be used to check if two variables refer to the same
List.  "isnot" does the opposite.  In contrast "==" compares if two lists have
the same value.
     :let alist = [1, 2, 3]
     :let blist = [1, 2, 3]
     :echo alist is blist
        0
     :echo alist == blist
        1

Note about comparing lists: Two lists are considered equal if they have the
same length and all items compare equal, as with using "==".  There is one
exception: When comparing a number with a string they are considered
different.  There is no automatic type conversion, as with using "==" on
variables.  Example:
     echo 4 == "4"
        1
     echo [4] == ["4"]
        0

Thus comparing Lists is more strict than comparing numbers and strings.  You
can compare simple values this way too by putting them in a string:

     :let a = 5
     :let b = "5"
     echo a == b
        1
     echo [a] == [b]
        0


List unpack 

To unpack the items in a list to individual variables, put the variables in
square brackets, like list items:
     :let [var1, var2] = mylist

When the number of variables does not match the number of items in the list
this produces an error.  To handle any extra items from the list append ";"
and a variable name:
     :let [var1, var2; rest] = mylist

This works like:
     :let var1 = mylist[0]
     :let var2 = mylist[1]
     :let rest = mylist[2:]

Except that there is no error if there are only two items.  "rest" will be an
empty list then.


List modification 

                                                        *list-modification*
To change a specific item of a list use |:let| this way:
     :let list[4] = "four"
     :let listlist[0][3] = item

To change part of a list you can specify the first and last item to be
modified.  The value must at least have the number of items in the range:
     :let list[3:5] = [3, 4, 5]

Adding and removing items from a list is done with functions.  Here are a few
examples:
     :call insert(list, 'a')         " prepend item 'a'
     :call insert(list, 'a', 3)      " insert item 'a' before list[3]
     :call add(list, "new")          " append String item
     :call add(list, [1, 2])         " append a List as one new item
     :call extend(list, [1, 2])      " extend the list with two more items
     :let i = remove(list, 3)        " remove item 3
     :unlet list[3]                  " idem
     :let l = remove(list, 3, -1)    " remove items 3 to last item
     :unlet list[3 : ]               " idem
     :call filter(list, 'v:val !~ "x"')  " remove items with an 'x'

Changing the order of items in a list:
     :call sort(list)                " sort a list alphabetically
     :call reverse(list)             " reverse the order of items


For loop 

The |:for| loop executes commands for each item in a list.  A variable is set
to each item in the list in sequence.  Example:
     :for item in mylist
     :   call Doit(item)
     :endfor

This works like:
     :let index = 0
     :while index < len(mylist)
     :   let item = mylist[index]
     :   :call Doit(item)
     :   let index = index + 1
     :endwhile

Note that all items in the list should be of the same type, otherwise this
results in error |E706|.  To avoid this |:unlet| the variable at the end of
the loop.

If all you want to do is modify each item in the list then the |map()|
function will be a simpler method than a for loop.

Just like the |:let| command, |:for| also accepts a list of variables.  This
requires the argument to be a list of lists.
     :for [lnum, col] in [[1, 3], [2, 8], [3, 0]]
     :   call Doit(lnum, col)
     :endfor

This works like a |:let| command is done for each list item.  Again, the types
must remain the same to avoid an error.

It is also possible to put remaining items in a List variable:
     :for [i, j; rest] in listlist
     :   call Doit(i, j)
     :   if !empty(rest)
     :      echo "remainder: " . string(rest)
     :   endif
     :endfor


List functions 

                                                *E714*
Functions that are useful with a List:
     :let r = call(funcname, list)   " call a function with an argument list
     :if empty(list)                 " check if list is empty
     :let l = len(list)              " number of items in list
     :let big = max(list)            " maximum value in list
     :let small = min(list)          " minimum value in list
     :let xs = count(list, 'x')      " count nr of times 'x' appears in list
     :let i = index(list, 'x')       " index of first 'x' in list
     :let lines = getline(1, 10)     " get ten text lines from buffer
     :call append('$', lines)        " append text lines in buffer
     :let list = split("a b c")      " create list from items in a string
     :let string = join(list, ', ')  " create string from list items
     :let s = string(list)           " String representation of list
     :call map(list, '">> " . v:val')  " prepend ">> " to each item

Don't forget that a combination of features can make things simple.  For
example, to add up all the numbers in a list:
     :exe 'let sum = ' . join(nrlist, '+')


1.4 Dictionaries 

                                                *Dictionaries* *Dictionary*
A Dictionary is an associative array: Each entry has a key and a value.  The
entry can be located with the key.  The entries are stored without a specific
ordering.


Dictionary creation 

                                                *E720* *E721* *E722* *E723*
A Dictionary is created with a comma separated list of entries in curly
braces.  Each entry has a key and a value, separated by a colon.  Each key can
only appear once.  Examples:
     :let mydict = {1: 'one', 2: 'two', 3: 'three'}
     :let emptydict = {}

                                                        *E713* *E716* *E717*
A key is always a String.  You can use a Number, it will be converted to a
String automatically.  Thus the String '4' and the number 4 will find the same
entry.  Note that the String '04' and the Number 04 are different, since the
Number will be converted to the String '4'.

A value can be any expression.  Using a Dictionary for a value creates a
nested Dictionary:
     :let nestdict = {1: {11: 'a', 12: 'b'}, 2: {21: 'c'}}

An extra comma after the last entry is ignored.


Accessing entries 

The normal way to access an entry is by putting the key in square brackets:
     :let val = mydict["one"]
     :let mydict["four"] = 4

You can add new entries to an existing Dictionary this way, unlike Lists.

For keys that consist entirely of letters, digits and underscore the following
form can be used YXXYexpr-entry|:
     :let val = mydict.one
     :let mydict.four = 4

Since an entry can be any type, also a List and a Dictionary, the indexing and
key lookup can be repeated:
     :echo dict.key[idx].key


Dictionary to List conversion 

You may want to loop over the entries in a dictionary.  For this you need to
turn the Dictionary into a List and pass it to |:for|.

Most often you want to loop over the keys, using the |keys()| function:
     :for key in keys(mydict)
     :   echo key . ': ' . mydict[key]
     :endfor

The List of keys is unsorted.  You may want to sort them first:
     :for key in sort(keys(mydict))

To loop over the values use the |values()| function: 
     :for v in values(mydict)
     :   echo "value: " . v
     :endfor

If you want both the key and the value use the |items()| function.  It returns
a List in which each item is a  List with two items, the key and the value:
     :for entry in items(mydict)
     :   echo entry[0] . ': ' . entry[1]
     :endfor


Dictionary identity 

                                                        *dict-identity*
Just like Lists you need to use |copy()| and |deepcopy()| to make a copy of a
Dictionary.  Otherwise, assignment results in referring to the same
Dictionary:
     :let onedict = {'a': 1, 'b': 2}
     :let adict = onedict
     :let adict['a'] = 11
     :echo onedict['a']
     11

Two Dictionaries compare equal if all the key-value pairs compare equal.  For
more info see |list-identity|.


Dictionary modification 

                                                        *dict-modification*
To change an already existing entry of a Dictionary, or to add a new entry,
use |:let| this way:
     :let dict[4] = "four"
     :let dict['one'] = item

Removing an entry from a Dictionary is done with |remove()| or |:unlet|.
Three ways to remove the entry with key "aaa" from dict:
     :let i = remove(dict, 'aaa')
     :unlet dict.aaa
     :unlet dict['aaa']

Merging a Dictionary with another is done with YXXYextend()|:
     :call extend(adict, bdict)
This extends adict with all entries from bdict.  Duplicate keys cause entries
in adict to be overwritten.  An optional third argument can change this.
Note that the order of entries in a Dictionary is irrelevant, thus don't
expect ":echo adict" to show the items from bdict after the older entries in
adict.

Weeding out entries from a Dictionary can be done with YXXYfilter()|:
     :call filter(dict 'v:val =~ "x"')
This removes all entries from "dict" with a value not matching 'x'.


Dictionary function 

                                        *Dictionary-function* *self* *E725*
When a function is defined with the "dict" attribute it can be used in a
special way with a dictionary.  Example:
     :function Mylen() dict
     :   return len(self.data)
     :endfunction
     :let mydict = {'data': [0, 1, 2, 3], 'len': function("Mylen")}
     :echo mydict.len()

This is like a method in object oriented programming.  The entry in the
Dictionary is a |Funcref|.  The local variable "self" refers to the dictionary
the function was invoked from.

It is also possible to add a function without the "dict" attribute as a
Funcref to a Dictionary, but the "self" variable is not available then.


                                *numbered-function* *anonymous-function*
To avoid the extra name for the function it can be defined and directly
assigned to a Dictionary in this way:
     :let mydict = {'data': [0, 1, 2, 3]}
     :function mydict.len() dict
     :   return len(self.data)
     :endfunction
     :echo mydict.len()

The function will then get a number and the value of dict.len is a |Funcref|
that references this function.  The function can only be used through a
|Funcref|.  It will automatically be deleted when there is no |Funcref|
remaining that refers to it.

It is not necessary to use the "dict" attribute for a numbered function.


Functions for Dictionaries 

                                                        *E715*
Functions that can be used with a Dictionary:
     :if has_key(dict, 'foo')        " TRUE if dict has entry with key "foo"
     :if empty(dict)                 " TRUE if dict is empty
     :let l = len(dict)              " number of items in dict
     :let big = max(dict)            " maximum value in dict
     :let small = min(dict)          " minimum value in dict
     :let xs = count(dict, 'x')      " count nr of times 'x' appears in dict
     :let s = string(dict)           " String representation of dict
     :call map(dict, '">> " . v:val')  " prepend ">> " to each item


1.5 More about variables 

                                                        *more-variables*
If you need to know the type of a variable or expression, use the |type()|
function.

When the '!' flag is included in the 'viminfo' option, global variables that
start with an uppercase letter, and don't contain a lowercase letter, are
stored in the viminfo file |viminfo-file|.

When the 'sessionoptions' option contains "global", global variables that
start with an uppercase letter and contain at least one lowercase letter are
stored in the session file |session-file|.

variable name           can be stored where 
my_var_6                not
My_Var_6                session file
MY_VAR_6                viminfo file


It's possible to form a variable name with curly braces, see
|curly-braces-names|.

==============================================================================

2. Expression syntax                                   *expression-syntax*

Expression syntax summary, from least to most significant:

|expr1| expr2 ? expr1 : expr1 if-then-else

|expr2|    expr3 || expr3 ..   logical OR

|expr3|    expr4 && expr4 ..     logical AND

|expr4|    expr5 == expr5           equal
        expr5 != expr5                not equal
        expr5 >      expr5             greater than
        expr5 >= expr5             greater than or equal
        expr5 <      expr5             smaller than
        expr5 <= expr5             smaller than or equal
        expr5 =~ expr5                regexp matches
        expr5 !~ expr5                regexp doesn't match

        expr5 ==? expr5          equal, ignoring case
        expr5 ==# expr5               equal, match case
        etc.                    As above, append ? for ignoring case, # for
                                matching case

        expr5 is expr5                same |List| instance
        expr5 isnot expr5     different |List| instance

|expr5|    expr6 +     expr6 ..  number addition or list concatenation
        expr6 -     expr6 ..  number subtraction
        expr6 .     expr6 ..  string concatenation

|expr6|    expr7 *         expr7 ..  number multiplication
        expr7 /     expr7 ..  number division
        expr7 %     expr7 ..  number modulo

|expr7|    ! expr7                 logical NOT
        - expr7                    unary minus
        + expr7                    unary plus


|expr8|    expr8[expr1]            byte of a String or item of a |List|
        expr8[expr1 : expr1]    substring of a String or sublist of a |List|
        expr8.name              entry in a |Dictionary|
        expr8(expr1, ...)       function call with |Funcref| variable

|expr9| number                     number constant
        "string"              string constant, backslash is special
        'string'                string constant, '' is doubled
        [expr1, ...]            |List|
        {expr1: expr1, ...}        |Dictionary|
        &option                     option value
        (expr1)                 nested expression
        variable                internal variable
        va{ria}ble              internal variable with curly braces
        $VAR                    environment variable
        @r                      contents of register 'r'
        function(expr1, ...)    function call
        func{ti}on(expr1, ...)  function call with curly braces


".." indicates that the operations in this level can be concatenated.
Example:
     &nu || &list && &shell == "csh"

All expressions within one level are parsed from left to right.



expr1                                                      *expr1* *E109*

expr2 ? expr1 : expr1

The expression before the '?' is evaluated to a number.  If it evaluates to
non-zero, the result is the value of the expression between the '?' and ':',
otherwise the result is the value of the expression after the ':'.
Example:
     :echo lnum == 1 ? "top" : lnum

Since the first expression is an "expr2", it cannot contain another ?:.  The
other two expressions can, thus allow for recursive use of ?:.
Example:
     :echo lnum == 1 ? "top" : lnum == 1000 ? "last" : lnum

To keep this readable, using |line-continuation| is suggested:
     :echo lnum == 1
     :\      ? "top"
     :\      : lnum == 1000
     :\              ? "last"
     :\              : lnum



expr2 and expr3                                               *expr2* *expr3*


                                        *expr-barbar* *expr-&&*
The "||" and "&&" operators take one argument on each side.  The arguments
are (converted to) Numbers.  The result is:

         input                           output 
n1              n2              n1 || n2        n1 && n2 
zero            zero            zero            zero
zero            non-zero        non-zero        zero
non-zero        zero            non-zero        zero
non-zero        non-zero        non-zero        non-zero

The operators can be concatenated, for example:

     &nu || &list && &shell == "csh"

Note that "&&" takes precedence over "||", so this has the meaning of:

     &nu || (&list && &shell == "csh")

Once the result is known, the expression "short-circuits", that is, further
arguments are not evaluated.  This is like what happens in C.  For example:

     let a = 1
     echo a || b

This is valid even if there is no variable called "b" because "a" is non-zero,
so the result must be non-zero.  Similarly below:

     echo exists("b") && b == "yes"

This is valid whether "b" has been defined or not.  The second clause will
only be evaluated if "b" has been defined.



expr4                                                      *expr4*

expr5 {cmp} expr5

Compare two expr5 expressions, resulting in a 0 if it evaluates to false, or 1
if it evaluates to true.


                        *expr-==*  *expr-!=*  *expr->*   *expr->=*

                        *expr-<*   *expr-<=*  *expr-=~*  *expr-!~*

                        *expr-==#* *expr-!=#* *expr->#*  *expr->=#*

                        *expr-<#*  *expr-<=#* *expr-=~#* *expr-!~#*

                        *expr-==?* *expr-!=?* *expr->?*  *expr->=?*

                        *expr-<?*  *expr-<=?* *expr-=~?* *expr-!~?*

                        *expr-is*
                use 'ignorecase'    match case     ignore case 
equal                   ==         ==#             ==?
not equal               !=              !=#             !=?
greater than            >                >#           >?
greater than or equal   >=           >=#          >=?
smaller than            <                <#           <?
smaller than or equal   <=           <=#          <=?
regexp matches                =~              =~#             =~?
regexp doesn't match  !~              !~#             !~?
same instance           is
different instance      isnot

Examples:
"abc" ==# "Abc"       evaluates to 0
"abc" ==? "Abc"          evaluates to 1
"abc" == "Abc"   evaluates to 1 if 'ignorecase' is set, 0 otherwise


                                                        *E691* *E692*
A |List| can only be compared with a |List| and only "equal", "not equal" and
"is" can be used.  This compares the values of the list, recursively.
Ignoring case means case is ignored when comparing item values.


                                                        *E735* *E736*
A |Dictionary| can only be compared with a |Dictionary| and only "equal", "not
equal" and "is" can be used.  This compares the key/values of the |Dictionary|
recursively.  Ignoring case means case is ignored when comparing item values.


                                                        *E693* *E694*
A |Funcref| can only be compared with a |Funcref| and only "equal" and "not
equal" can be used.  Case is never ignored.

When using "is" or "isnot" with a |List| this checks if the expressions are
referring to the same |List| instance.  A copy of a |List| is different from
the original |List|.  When using "is" without a |List| it is equivalent to
using "equal", using "isnot" equivalent to using "not equal".  Except that a
different type means the values are different.  "4 == '4'"' is true, "4 is '4'"'
is false.

When comparing a String with a Number, the String is converted to a Number,
and the comparison is done on Numbers.  This means that "0 == 'x'"' is TRUE,
because 'x' converted to a Number is zero.

When comparing two Strings, this is done with strcmp() or stricmp().  This
results in the mathematical difference (comparing byte values), not
necessarily the alphabetical difference in the local language.

When using the operators with a trailing '#", or the short version and
'ignorecase' is off, the comparing is done with strcmp().

When using the operators with a trailing '?', or the short version and
'ignorecase' is set, the comparing is done with stricmp().

The "=~" and "!~" operators match the lefthand argument with the righthand
argument, which is used as a pattern.  See |pattern| for what a pattern is.
This matching is always done like 'magic' was set and 'cpoptions' is empty, no
matter what the actual value of 'magic' or 'cpoptions' is.  This makes scripts
portable.  To avoid backslashes in the regexp pattern to be doubled, use a
single-quote string, see |literal-string|.
Since a string is considered to be a single line, a multi-line pattern
(containing \n, backslash-n) will not match.  However, a literal NL character
can be matched like an ordinary character.  Examples:
        "foo\nbar" =~ "\n"  evaluates to 1
        "foo\nbar" =~ "\\n" evaluates to 0



expr5 and expr6                                               *expr5* *expr6*

expr6 +     expr6 ..  Number addition or |List| concatenation     *expr-+*

expr6 -     expr6 ..  Number subtraction                      *expr--*

expr6 .     expr6 ..  String concatenation                    *expr-.*

For |Lists| only "+" is possible and then both expr6 must be a list.  The
result is a new list with the two lists Concatenated.


expr7 *         expr7 ..  number multiplication                   *expr-star*

expr7 /     expr7 ..  number division                         *expr-/*

expr7 %     expr7 ..  number modulo                           *expr-%*

For all, except ".", Strings are converted to Numbers.

Note the difference between "+" and ".":
        "123" + "456" = 579
        "123" . "456" = "123456"

When the righthand side of '/' is zero, the result is 0x7fffffff.
When the righthand side of '%' is zero, the result is 0.

None of these work for |Funcref|s.



expr7                                                      *expr7*

! expr7                    logical NOT             *expr-!*

- expr7                    unary minus             *expr-unary--*

+ expr7                    unary plus              *expr-unary-+*

For '!' non-zero becomes zero, zero becomes one.
For '-' the sign of the number is changed.
For '+' the number is unchanged.

A String will be converted to a Number first.

These three can be repeated and mixed.  Examples:
        !-1         == 0
        !!8         == 1
        --9         == 9



expr8                                                      *expr8*

expr8[expr1]            item of String or |List|    *expr-[]* *E111*

If expr8 is a Number or String this results in a String that contains the
expr1'th single byte from expr8.  expr8 is used as a String, expr1 as a
Number.  Note that this doesn't recognize multi-byte encodings.

Index zero gives the first character.  This is like it works in C.  Careful:
text column numbers start with one!  Example, to get the character under the
cursor:
     :let c = getline(".")[col(".") - 1]

If the length of the String is less than the index, the result is an empty
String.  A negative index always results in an empty string (reason: backwards
compatibility).  Use [-1:] to get the last byte.

If expr8 is a |List| then it results the item at index expr1.  See |list-index|
for possible index values.  If the index is out of range this results in an
error.  Example:
     :let item = mylist[-1]          " get last item

Generally, if a |List| index is equal to or higher than the length of the
|List|, or more negative than the length of the |List|, this results in an
error.



expr8[expr1a : expr1b]  substring or sublist            *expr-[:]*

If expr8 is a Number or String this results in the substring with the bytes
from expr1a to and including expr1b.  expr8 is used as a String, expr1a and
expr1b are used as a Number.  Note that this doesn't recognize multi-byte
encodings.

If expr1a is omitted zero is used.  If expr1b is omitted the length of the
string minus one is used.

A negative number can be used to measure from the end of the string.  -1 is
the last character, -2 the last but one, etc.

If an index goes out of range for the string characters are omitted.  If
expr1b is smaller than expr1a the result is an empty string.

Examples:
     :let c = name[-1:]              " last byte of a string
     :let c = name[-2:-2]            " last but one byte of a string
     :let s = line(".")[4:]          " from the fifth byte to the end
     :let s = s[:-3]                 " remove last two bytes

If expr8 is a |List| this results in a new |List| with the items indicated by
the indexes expr1a and expr1b.  This works like with a String, as explained
just above, except that indexes out of range cause an error.  Examples:
     :let l = mylist[:3]             " first four items
     :let l = mylist[4:4]            " List with one item
     :let l = mylist[:]              " shallow copy of a List

Using expr8[expr1] or expr8[expr1a : expr1b] on a |Funcref| results in an
error.



expr8.name              entry in a |Dictionary|               *expr-entry*

If expr8 is a |Dictionary| and it is followed by a dot, then the following
name will be used as a key in the |Dictionary|.  This is just like:
expr8[name].

The name must consist of alphanumeric characters, just like a variable name,
but it may start with a number.  Curly braces cannot be used.

There must not be white space before or after the dot.

Examples:
     :let dict = {"one": 1, 2: "two"}
     :echo dict.one
     :echo dict .2

Note that the dot is also used for String concatenation.  To avoid confusion
always put spaces around the dot for String concatenation.


expr8(expr1, ...)       |Funcref| function call

When expr8 is a |Funcref| type variable, invoke the function it refers to.




                                                        *expr9*
number

number                  number constant         *expr-number*

Decimal, Hexadecimal (starting with 0x or 0X), or Octal (starting with 0).



string                                                  *expr-string* *E114*

"string"              string constant         *expr-quote*

Note that double quotes are used.

A string constant accepts these special characters:
\...    three-digit octal number (e.g., "\316")
\..     two-digit octal number (must be followed by non-digit)
\.      one-digit octal number (must be followed by non-digit)
\x..    byte specified with two hex numbers (e.g., "\x1f")
\x.     byte specified with one hex number (must be followed by non-hex char)
\X..    same as \x..
\X.     same as \x.
\u....  character specified with up to 4 hex numbers, stored according to the
        current value of 'encoding' (e.g., "\u02a4")
\U....  same as \u....
\b      backspace <BS>
\e      escape <Esc>
\f      formfeed <FF>
\n      newline <NL>
\r      return <CR>
\t      tab <Tab>
\\      backslash
\" double quote
\<xxx>    Special key named "xxx".  e.g. "\<C-W>" for CTRL-W.

Note that "\000" and "\x00" force the end of the string.



literal-string                                            *literal-string* *E115*

'string'                string constant                 *expr-'*

Note that single quotes are used.

This string is taken as it is.  No backslashes are removed or have a special
meaning.  The only exception is that two quotes stand for one quote.

Single quoted strings are useful for patterns, so that backslashes do not need
to be doubled.  These two commands are equivalent:
     if a =~ "\\s*"
     if a =~ '\s*'



option                                          *expr-option* *E112* *E113*
&option                     option value, local value if possible
&g:option           global option value
&l:option           local option value

Examples:
     echo "tabstop is " . &tabstop
     if &insertmode

Any option name can be used here.  See |options|.  When using the local value
and there is no buffer-local or window-local value, the global value is used
anyway.



register                                            *expr-register*
@r                      contents of register 'r'

The result is the contents of the named register, as a single string.
Newlines are inserted where required.  To get the contents of the unnamed
register use @" or @@.  See |registers| for an explanation of the available
registers.

When using the '=' register you get the expression itself, not what it
evaluates to.  Use |eval()| to evaluate it.



nesting                                                 *expr-nesting* *E110*
(expr1)                 nested expression



environment variable                                    *expr-env*
$VAR                    environment variable

The String value of any environment variable.  When it is not defined, the
result is an empty string.

                                                *expr-env-expand*
Note that there is a difference between using $VAR directly and using
expand("$VAR").  Using it directly will only expand environment variables that
are known inside the current Vim session.  Using expand() will first try using
the environment variables known inside the current Vim session.  If that
fails, a shell will be used to expand the variable.  This can be slow, but it
does expand all variables that the shell knows about.  Example:
     :echo $version
     :echo expand("$version")
The first one probably doesn't echo anything, the second echoes the $version
variable (if your shell supports it).



internal variable                                       *expr-variable*
variable                internal variable
See below |internal-variables|.



function call           *expr-function* *E116* *E118* *E119* *E120*
function(expr1, ...)    function call
See below |functions|.


==============================================================================

3. Internal variable                            *internal-variables* *E121*

                                                                        *E461*
An internal variable name can be made up of letters, digits and '_'.  But it
cannot start with a digit.  It's also possible to use curly braces, see
|curly-braces-names|.

An internal variable is created with the ":let" command |:let|.
An internal variable is explicitly destroyed with the ":unlet" command
|:unlet|.
Using a name that is not an internal variable or refers to a variable that has
been destroyed results in an error.

There are several name spaces for variables.  Which one is to be used is
specified by what is prepended:

                (nothing) In a function: local to a function; otherwise: global
|buffer-variable|    b:    Local to the current buffer.
|window-variable|    w:    Local to the current window.
|tabpage-variable|   t:   Local to the current tab page.
|global-variable|    g:    Global.
|local-variable|     l:     Local to a function.
|script-variable|    s:    Local to a |:source|'ed Vim script.
|function-argument|  a:          Function argument (only inside a function).
|vim-variable|       v:       Global, predefined by Vim.

The scope name by itself can be used as a |Dictionary|.  For example, to
delete all script-local variables:
     :for k in keys(s:)
     :    unlet s:[k]
     :endfor
 

                                                *buffer-variable* *b:var*
A variable name that is preceded with "b:" is local to the current buffer.
Thus you can have several "b:foo" variables, one for each buffer.
This kind of variable is deleted when the buffer is wiped out or deleted with
|:bdelete|.

One local buffer variable is predefined:

                                        *b:changedtick-variable* *changetick*
b:changedtick   The total number of changes to the current buffer.  It is
                incremented for each change.  An undo command is also a change
                in this case.  This can be used to perform an action only when
                the buffer has changed.  Example:
                 :if my_changedtick != b:changedtick
                 :   let my_changedtick = b:changedtick
                 :   call My_Update()
                 :endif
 

                                                *window-variable* *w:var*
A variable name that is preceded with "w:" is local to the current window.  It
is deleted when the window is closed.


                                                *tabpage-variable* *t:var*
A variable name that is preceded with "t:" is local to the current tab page,
It is deleted when the tab page is closed. {not available when compiled
without the +windows feature}


                                                *global-variable* *g:var*
Inside functions global variables are accessed with "g:".  Omitting this will
access a variable local to a function.  But "g:" can also be used in any other
place if you like.


                                                *local-variable* *l:var*
Inside functions local variables are accessed without prepending anything.
But you can also prepend "l:" if you like.


                                                *script-variable* *s:var*
In a Vim script variables starting with "s:" can be used.  They cannot be
accessed from outside of the scripts, thus are local to the script.

They can be used in:
- commands executed while the script is sourced
- functions defined in the script
- autocommands defined in the script
- functions and autocommands defined in functions and autocommands which were
  defined in the script (recursively)
- user defined commands defined in the script
Thus not in:
- other scripts sourced from this one
- mappings
- etc.

script variables can be used to avoid conflicts with global variable names.
Take this example:

        let s:counter = 0
        function MyCounter()
          let s:counter = s:counter + 1
          echo s:counter
        endfunction
        command Tick call MyCounter()

You can now invoke "Tick" from any script, and the "s:counter" variable in
that script will not be changed, only the "s:counter" in the script where
"Tick" was defined is used.

Another example that does the same:

     let s:counter = 0
     command Tick let s:counter = s:counter + 1 | echo s:counter

When calling a function and invoking a user-defined command, the context for
script variables is set to the script where the function or command was
defined.

The script variables are also available when a function is defined inside a
function that is defined in a script.  Example:

     let s:counter = 0
     function StartCounting(incr)
       if a:incr
         function MyCounter()
           let s:counter = s:counter + 1
         endfunction
       else
         function MyCounter()
           let s:counter = s:counter - 1
         endfunction
       endif
     endfunction

This defines the MyCounter() function either for counting up or counting down
when calling StartCounting().  It doesn't matter from where StartCounting() is
called, the s:counter variable will be accessible in MyCounter().

When the same script is sourced again it will use the same script variables.
They will remain valid as long as Vim is running.  This can be used to
maintain a counter:

     if !exists("s:counter")
       let s:counter = 1
       echo "script executed for the first time"
     else
       let s:counter = s:counter + 1
       echo "script executed " . s:counter . " times now"
     endif

Note that this means that filetype plugins don't get a different set of script
variables for each buffer.  Use local buffer variables instead |b:var|.



Predefined Vim variables:                      *vim-variable* *v:var*


                                        *v:beval_col* *beval_col-variable*
v:beval_col  The number of the column, over which the mouse pointer is.
                This is the byte index in the |v:beval_lnum| line.
                Only valid while evaluating the 'balloonexpr' option.


                                        *v:beval_bufnr* *beval_bufnr-variable*
v:beval_bufnr      The number of the buffer, over which the mouse pointer is. Only
                valid while evaluating the 'balloonexpr' option.


                                        *v:beval_lnum* *beval_lnum-variable*
v:beval_lnum        The number of the line, over which the mouse pointer is. Only
                valid while evaluating the 'balloonexpr' option.


                                        *v:beval_text* *beval_text-variable*
v:beval_text        The text under or after the mouse pointer.  Usually a word as
                it is useful for debugging a C program.  'iskeyword' applies,
                but a dot and "->" before the position is included.  When on a
                ']' the text before it is used, including the matching '[' and
                word before it.  When on a Visual area within one line the
                highlighted text is used.
                Only valid while evaluating the 'balloonexpr' option.


                                        *v:beval_winnr* *beval_winnr-variable*
v:beval_winnr      The number of the window, over which the mouse pointer is. Only
                valid while evaluating the 'balloonexpr' option.


                                        *v:char* *char-variable*
v:char            Argument for evaluating 'formatexpr'.


                        *v:charconvert_from* *charconvert_from-variable*
v:charconvert_from
                The name of the character encoding of a file to be converted.
                Only valid while evaluating the 'charconvert' option.


                        *v:charconvert_to* *charconvert_to-variable*
v:charconvert_to
                The name of the character encoding of a file after conversion.
                Only valid while evaluating the 'charconvert' option.


                                        *v:cmdarg* *cmdarg-variable*
v:cmdarg        This variable is used for two purposes:
                1. The extra arguments given to a file read/write command.
                   Currently these are "++enc=" and "++ff=".  This variable is
                   set before an autocommand event for a file read/write
                   command is triggered.  There is a leading space to make it
                   possible to append this variable directly after the
                   read/write command.  Note: The "+cmd" argument isn't
                   included here, because it will be executed anyway.
                2. When printing a PostScript file with ":hardcopy" this is
                   the argument for the ":hardcopy" command.  This can be used
                   in 'printexpr'.


                                        *v:cmdbang* *cmdbang-variable*
v:cmdbang      Set like v:cmdarg for a file read/write command.  When a "!"
                was used the value is 1, otherwise it is 0.  Note that this
                can only be used in autocommands.  For user commands |<bang>|
                can be used.


                                        *v:count* *count-variable*
v:count          The count given for the last Normal mode command.  Can be used
                to get the count before a mapping.  Read-only.  Example:
     :map _x :<C-U>echo "the count is " . v:count<CR>
                Note: The <C-U> is required to remove the line range that you
                get when typing ':' after a count.
                Also used for evaluating the 'formatexpr' option.
                "count" also works, for backwards compatibility.


                                        *v:count1* *count1-variable*
v:count1        Just like "v:count", but defaults to one when no count is
                used.


                                                *v:ctype* *ctype-variable*
v:ctype          The current locale setting for characters of the runtime
                environment.  This allows Vim scripts to be aware of the
                current locale encoding.  Technical: it's the value of
                LC_CTYPE.  When not using a locale the value is "C".
                This variable can not be set directly, use the |:language|
                command.
                See |multi-lang|.


                                        *v:dying* *dying-variable*
v:dying          Normally zero.  When a deadly signal is caught it's set to
                one.  When multiple signals are caught the number increases.
                Can be used in an autocommand to check if Vim didn't
                terminate normally. {only works on Unix}
                Example:
     :au VimLeave * if v:dying | echo "\nAAAAaaaarrrggghhhh!!!\n" | endif
 

                                        *v:errmsg* *errmsg-variable*
v:errmsg        Last given error message.  It's allowed to set this variable.
                Example:
     :let v:errmsg = ""
     :silent! next
     :if v:errmsg != ""
     :  ... handle error
                "errmsg" also works, for backwards compatibility.


                                        *v:exception* *exception-variable*
v:exception  The value of the exception most recently caught and not
                finished.  See also |v:throwpoint| and |throw-variables|.
                Example:
     :try
     :  throw "oops"
     :catch /.*/
     :  echo "caught" v:exception
     :endtry
                Output: "caught oops".


                                        *v:fcs_reason* *fcs_reason-variable*
v:fcs_reason        The reason why the |FileChangedShell| event was triggered.
                Can be used in an autocommand to decide what to do and/or what
                to set v:fcs_choice to.  Possible values:
                        deleted         file no longer exists
                        conflict        file contents, mode or timestamp was
                                        changed and buffer is modified
                        changed         file contents has changed
                        mode            mode of file changed
                        time            only file timestamp changed


                                        *v:fcs_choice* *fcs_choice-variable*
v:fcs_choice        What should happen after a |FileChangedShell| event was
                triggered.  Can be used in an autocommand to tell Vim what to
                do with the affected buffer:
                        reload          Reload the buffer (does not work if
                                        the file was deleted).
                        ask             Ask the user what to do, as if there
                                        was no autocommand.  Except that when
                                        only the timestamp changed nothing
                                        will happen.
                        <empty>           Nothing, the autocommand should do
                                        everything that needs to be done.
                The default is empty.  If another (invalid) value is used then
                Vim behaves like it is empty, there is no warning message.


                                        *v:fname_in* *fname_in-variable*
v:fname_in    The name of the input file.  Valid while evaluating:
                        option          used for 
                        'charconvert'  file to be converted
                        'diffexpr'        original file
                        'patchexpr'      original file
                        'printexpr'      file to be printed
                And set to the swap file name for |SwapExists|.


                                        *v:fname_out* *fname_out-variable*
v:fname_out  The name of the output file.  Only valid while
                evaluating:
                        option          used for 
                        'charconvert'  resulting converted file (*)
                        'diffexpr'        output of diff
                        'patchexpr'      resulting patched file
                (*) When doing conversion for a write command (e.g., ":w
                file") it will be equal to v:fname_in.  When doing conversion
                for a read command (e.g., ":e file") it will be a temporary
                file and different from v:fname_in.


                                        *v:fname_new* *fname_new-variable*
v:fname_new  The name of the new version of the file.  Only valid while
                evaluating 'diffexpr'.


                                        *v:fname_diff* *fname_diff-variable*
v:fname_diff        The name of the diff (patch) file.  Only valid while
                evaluating 'patchexpr'.


                                        *v:folddashes* *folddashes-variable*
v:folddashes        Used for 'foldtext': dashes representing foldlevel of a closed
                fold.
                Read-only in the |sandbox|. |fold-foldtext|


                                        *v:foldlevel* *foldlevel-variable*
v:foldlevel  Used for 'foldtext': foldlevel of closed fold.
                Read-only in the |sandbox|. |fold-foldtext|


                                        *v:foldend* *foldend-variable*
v:foldend      Used for 'foldtext': last line of closed fold.
                Read-only in the |sandbox|. |fold-foldtext|


                                        *v:foldstart* *foldstart-variable*
v:foldstart  Used for 'foldtext': first line of closed fold.
                Read-only in the |sandbox|. |fold-foldtext|


                                        *v:insertmode* *insertmode-variable*
v:insertmode        Used for the |InsertEnter| and |InsertChange| autocommand
                events.  Values:
                        i   Insert mode
                        r   Replace mode
                        v   Virtual Replace mode


                                                *v:key* *key-variable*
v:key              Key of the current item of a |Dictionary|.  Only valid while
                evaluating the expression used with |map()| and |filter()|.
                Read-only.


                                                *v:lang* *lang-variable*
v:lang            The current locale setting for messages of the runtime
                environment.  This allows Vim scripts to be aware of the
                current language.  Technical: it's the value of LC_MESSAGES.
                The value is system dependent.
                This variable can not be set directly, use the |:language|
                command.
                It can be different from |v:ctype| when messages are desired
                in a different language than what is used for character
                encoding.  See |multi-lang|.


                                                *v:lc_time* *lc_time-variable*
v:lc_time      The current locale setting for time messages of the runtime
                environment.  This allows Vim scripts to be aware of the
                current language.  Technical: it's the value of LC_TIME.
                This variable can not be set directly, use the |:language|
                command.  See |multi-lang|.


                                                *v:lnum* *lnum-variable*
v:lnum            Line number for the 'foldexpr' |fold-expr| and 'indentexpr'
                expressions, tab page number for 'guitablabel' and
                'guitabtooltip'.  Only valid while one of these expressions is
                being evaluated.  Read-only when in the |sandbox|.


                                        *v:prevcount* *prevcount-variable*
v:prevcount  The count given for the last but one Normal mode command.
                This is the v:count value of the previous command.  Useful if
                you want to cancel Visual mode and then use the count.
                     :vmap % <Esc>:call MyFilter(v:prevcount)<CR>
                Read-only.


                                        *v:profiling* *profiling-variable*
v:profiling  Normally zero.  Set to one after using ":profile start".
                See |profiling|.


                                        *v:progname* *progname-variable*
v:progname    Contains the name (with path removed) with which Vim was
                invoked.  Allows you to do special initialisations for "view",
                "evim" etc., or any other name you might symlink to Vim.
                Read-only.


                                        *v:register* *register-variable*
v:register    The name of the register supplied to the last normal mode
                command.  Empty if none were supplied. |getreg()| |setreg()|


                                        *v:scrollstart* *scrollstart-variable*
v:scrollstart      String describing the script or function that caused the
                screen to scroll up.  It's only set when it is empty, thus the
                first reason is remembered.  It is set to "Unknown" for a
                typed command.
                This can be used to find out why your script causes the
                hit-enter prompt.


                                        *v:servername* *servername-variable*
v:servername        The resulting registered |x11-clientserver| name if any.
                Read-only.


                                        *v:shell_error* *shell_error-variable*
v:shell_error      Result of the last shell command.  When non-zero, the last
                shell command had an error.  When zero, there was no problem.
                This only works when the shell returns the error code to Vim.
                The value -1 is often used when the command could not be
                executed.  Read-only.
                Example:
     :!mv foo bar
     :if v:shell_error
     :  echo 'could not rename "foo" to "bar"!'
     :endif
                "shell_error" also works, for backwards compatibility.


                                        *v:statusmsg* *statusmsg-variable*
v:statusmsg  Last given status message.  It's allowed to set this variable.


                                        *v:swapname* *swapname-variable*
v:swapname    Only valid when executing |SwapExists| autocommands: Name of
                the swap file found.  Read-only.


                                        *v:swapchoice* *swapchoice-variable*
v:swapchoice        |SwapExists| autocommands can set this to the selected choice
                for handling an existing swap file:
                        'o' Open read-only
                        'e' Edit anyway
                        'r' Recover
                        'd' Delete swapfile
                        'q' Quit
                        'a' Abort
                The value should be a single-character string.  An empty value
                results in the user being asked, as would happen when there is
                no SwapExists autocommand.  The default is empty.


                                        *v:swapcommand* *swapcommand-variable*
v:swapcommand      Normal mode command to be executed after a file has been
                opened.  Can be used for a |SwapExists| autocommand to have
                another Vim open the file and jump to the right place.  For
                example, when jumping to a tag the value is ":tag tagname\r".
                For ":edit +cmd file" the value is ":cmd\r".


                                *v:termresponse* *termresponse-variable*
v:termresponse    The escape sequence returned by the terminal for the |t_RV|
                termcap entry.  It is set when Vim receives an escape sequence
                that starts with ESC [ or CSI and ends in a 'c', with only
                digits, ';' and '.' in between.
                When this option is set, the TermResponse autocommand event is
                fired, so that you can react to the response from the
                terminal.
                The response from a new xterm is: "<Esc>[ Pp ; Pv ; Pc c".  Pp
                is the terminal type: 0 for vt100 and 1 for vt220.  Pv is the
                patch level (since this was introduced in patch 95, it's
                always 95 or bigger).  Pc is always zero.
                {only when compiled with |+termresponse| feature}


                                *v:this_session* *this_session-variable*
v:this_session    Full filename of the last loaded or saved session file.  See
                |:mksession|.  It is allowed to set this variable.  When no
                session file has been saved, this variable is empty.
                "this_session" also works, for backwards compatibility.


                                        *v:throwpoint* *throwpoint-variable*
v:throwpoint        The point where the exception most recently caught and not
                finished was thrown.  Not set when commands are typed.  See
                also |v:exception| and |throw-variables|.
                Example:
     :try
     :  throw "oops"
     :catch /.*/
     :  echo "Exception from" v:throwpoint
     :endtry
                Output: "Exception from test.vim, line 2"


                                                *v:val* *val-variable*
v:val              Value of the current item of a |List| or |Dictionary|.  Only
                valid while evaluating the expression used with |map()| and
                |filter()|.  Read-only.


                                        *v:version* *version-variable*
v:version      Version number of Vim: Major version number times 100 plus
                minor version number.  Version 5.0 is 500.  Version 5.1 (5.01)
                is 501.  Read-only.  "version" also works, for backwards
                compatibility.
                Use |has()| to check if a certain patch was included, e.g.:
                     if has("patch123")
                Note that patch numbers are specific to the version, thus both
                version 5.0 and 5.1 may have a patch 123, but these are
                completely different.


                                        *v:warningmsg* *warningmsg-variable*
v:warningmsg        Last given warning message.  It's allowed to set this variable.

==============================================================================

4. Builtin Functions                                    *functions*

See |function-list| for a list grouped by what the function is used for.

(Use CTRL-] on the function name to jump to the full explanation.)

USAGE                           RESULT  DESCRIPTION     

add( {list}, {item})            List    append {item} to |List| {list}
append( {lnum}, {string})       Number  append {string} below line {lnum}
append( {lnum}, {list})         Number  append lines {list} below line {lnum}
argc()                            Number  number of files in the argument list
argidx()                        Number  current index in the argument list
argv( {nr})                     String  {nr} entry of the argument list
argv( )                         List        the argument list
browse( {save}, {title}, {initdir}, {default})
                                String  put up a file requester
browsedir( {title}, {initdir})  String  put up a directory requester
bufexists( {expr})              Number  TRUE if buffer {expr} exists
buflisted( {expr})              Number  TRUE if buffer {expr} is listed
bufloaded( {expr})              Number  TRUE if buffer {expr} is loaded
bufname( {expr})                String  Name of the buffer {expr}
bufnr( {expr})                  Number  Number of the buffer {expr}
bufwinnr( {expr})               Number  window number of buffer {expr}
byte2line( {byte})              Number  line number at byte count {byte}
byteidx( {expr}, {nr})          Number  byte index of {nr}'th char in {expr}
call( {func}, {arglist} [, {dict}])
                                any     call {func} with arguments {arglist}
changenr()                    Number  current change number
char2nr( {expr})                Number  ASCII value of first char in {expr}
cindent( {lnum})                Number  C indent for line {lnum}
col( {expr})                    Number  column nr of cursor or mark
complete({startcol}, {matches}) String  set Insert mode completion
complete_add( {expr})           Number  add completion match
complete_check()                Number  check for key typed during completion
confirm( {msg} [, {choices} [, {default} [, {type}]]])
                                Number  number of choice picked by user
copy( {expr})                   any     make a shallow copy of {expr}
count( {list}, {expr} [, {start} [, {ic}]])
                                Number   count how many {expr} are in {list}
cscope_connection( [{num} , {dbpath} [, {prepend}]])
                                Number  checks existence of cscope connection
cursor( {lnum}, {col} [, {coladd}])
                                Number  move cursor to {lnum}, {col}, {coladd}
cursor( {list})                 Number  move cursor to position in {list}
deepcopy( {expr})               any     make a full copy of {expr}
delete( {fname})                Number  delete file {fname}
did_filetype()                    Number  TRUE if FileType autocommand event used
diff_filler( {lnum})            Number  diff filler lines about {lnum}
diff_hlID( {lnum}, {col})       Number  diff highlighting at {lnum}/{col}
empty( {expr})                  Number  TRUE if {expr} is empty
escape( {string}, {chars})      String  escape {chars} in {string} with '\'
eval( {string})                 any     evaluate {string} into its value
eventhandler( )                 Number  TRUE if inside an event handler
executable( {expr})             Number  1 if executable {expr} exists
exists( {expr})                 Number  TRUE if {expr} exists
extend({expr1}, {expr2} [, {expr3}])
                                List/Dict insert items of {expr2} into {expr1}
expand( {expr})                 String  expand special keywords in {expr}
feedkeys( {string} [, {mode}])  Number  add key sequence to typeahead buffer
filereadable( {file})         Number  TRUE if {file} is a readable file
filewritable( {file})         Number  TRUE if {file} is a writable file
filter( {expr}, {string})       List/Dict  remove items from {expr} where
                                        {string} is 0
finddir( {name}[, {path}[, {count}]])
                                String  find directory {name} in {path}
findfile( {name}[, {path}[, {count}]])
                                String  find file {name} in {path}
fnamemodify( {fname}, {mods})   String  modify file name
foldclosed( {lnum})             Number  first line of fold at {lnum} if closed
foldclosedend( {lnum})          Number  last line of fold at {lnum} if closed
foldlevel( {lnum})              Number  fold level at {lnum}
foldtext( )                     String  line displayed for closed fold
foldtextresult( {lnum})         String  text for closed fold at {lnum}
foreground( )                   Number  bring the Vim window to the foreground
function( {name})               Funcref reference to function {name}
garbagecollect()                none    free memory, breaking cyclic references
get( {list}, {idx} [, {def}])   any     get item {idx} from {list} or {def}
get( {dict}, {key} [, {def}])   any     get item {key} from {dict} or {def}
getbufline( {expr}, {lnum} [, {end}])
                                List        lines {lnum} to {end} of buffer {expr}
getbufvar( {expr}, {varname})   any     variable {varname} in buffer {expr}
getchar( [expr])                Number  get one character from the user
getcharmod( )                   Number  modifiers for the last typed character
getcmdline()                        String  return the current command-line
getcmdpos()                  Number  return cursor position in command-line
getcmdtype()                        String  return the current command-line type
getcwd()                        String  the current working directory
getfperm( {fname})              String  file permissions of file {fname}
getfsize( {fname})              Number  size in bytes of file {fname}
getfontname( [{name}])          String  name of font being used
getftime( {fname})              Number  last modification time of file
getftype( {fname})              String  description of type of file {fname}
getline( {lnum})                String  line {lnum} of current buffer
getline( {lnum}, {end})         List        lines {lnum} to {end} of current buffer
getloclist({nr})                List        list of location list items
getpos( {expr})                 List        position of cursor, mark, etc.
getqflist()                  List        list of quickfix items
getreg( [{regname} [, 1]])      String  contents of register
getregtype( [{regname}])        String  type of register
gettabwinvar( {tabnr}, {winnr}, {name})
                                any     {name} in {winnr} in tab page {tabnr}
getwinposx()                        Number  X coord in pixels of GUI Vim window
getwinposy()                        Number  Y coord in pixels of GUI Vim window
getwinvar( {nr}, {varname})     any     variable {varname} in window {nr}
glob( {expr})                   String  expand file wildcards in {expr}
globpath( {path}, {expr})       String  do glob({expr}) for all dirs in {path}
has( {feature})                 Number  TRUE if feature {feature} supported
has_key( {dict}, {key})         Number  TRUE if {dict} has entry {key}
hasmapto( {what} [, {mode} [, {abbr}]])
                                Number  TRUE if mapping to {what} exists
histadd( {history},{item})      String  add an item to a history
histdel( {history} [, {item}])  String  remove an item from a history
histget( {history} [, {index}]) String  get the item {index} from a history
histnr( {history})              Number  highest index of a history
hlexists( {name})               Number  TRUE if highlight group {name} exists
hlID( {name})                   Number  syntax ID of highlight group {name}
hostname()                    String  name of the machine Vim is running on
iconv( {expr}, {from}, {to})    String  convert encoding of {expr}
indent( {lnum})                 Number  indent of line {lnum}
index( {list}, {expr} [, {start} [, {ic}]])
                                Number  index in {list} where {expr} appears
input( {prompt} [, {text} [, {completion}]])
                                String  get input from the user
inputdialog( {p} [, {t} [, {c}]]) String  like input() but in a GUI dialog
inputlist( {textlist})          Number  let the user pick from a choice list
inputrestore()                    Number  restore typeahead
inputsave()                  Number  save and clear typeahead
inputsecret( {prompt} [, {text}]) String  like input() but hiding the text
insert( {list}, {item} [, {idx}]) List      insert {item} in {list} [before {idx}]
isdirectory( {directory})       Number  TRUE if {directory} is a directory
islocked( {expr})               Number  TRUE if {expr} is locked
items( {dict})                  List        key-value pairs in {dict}
join( {list} [, {sep}])         String  join {list} items into one String
keys( {dict})                   List        keys in {dict}
len( {expr})                    Number  the length of {expr}
libcall( {lib}, {func}, {arg})  String  call {func} in library {lib} with {arg}
libcallnr( {lib}, {func}, {arg})  Number  idem, but return a Number
line( {expr})                   Number  line nr of cursor, last line or mark
line2byte( {lnum})              Number  byte count of line {lnum}
lispindent( {lnum})             Number  Lisp indent for line {lnum}
localtime()                  Number  current time
map( {expr}, {string})          List/Dict  change each item in {expr} to {expr}
maparg( {name}[, {mode} [, {abbr}]])
                                String  rhs of mapping {name} in mode {mode}
mapcheck( {name}[, {mode} [, {abbr}]])
                                String  check for mappings matching {name}
match( {expr}, {pat}[, {start}[, {count}]])
                                Number  position where {pat} matches in {expr}
matcharg( {nr})                 List        arguments of |:match|
matchend( {expr}, {pat}[, {start}[, {count}]])
                                Number  position where {pat} ends in {expr}
matchlist( {expr}, {pat}[, {start}[, {count}]])
                                List        match and submatches of {pat} in {expr}
matchstr( {expr}, {pat}[, {start}[, {count}]])
                                String  {count}'th match of {pat} in {expr}
max({list})                     Number  maximum value of items in {list}
min({list})                     Number  minumum value of items in {list}
mkdir({name} [, {path} [, {prot}]])
                                Number  create directory {name}
mode()                            String  current editing mode
nextnonblank( {lnum})           Number  line nr of non-blank line >= {lnum}
nr2char( {expr})                String  single char with ASCII value {expr}
pathshorten( {expr})            String  shorten directory names in a path
prevnonblank( {lnum})           Number  line nr of non-blank line <= {lnum}
printf( {fmt}, {expr1}...)      String  format text
pumvisible()                        Number  whether popup menu is visible
range( {expr} [, {max} [, {stride}]])
                                List        items from {expr} to {max}
readfile({fname} [, {binary} [, {max}]])
                                List        get list of lines from file {fname}
reltime( [{start} [, {end}]])   List        get time value
reltimestr( {time})             String  turn time value into a String
remote_expr( {server}, {string} [, {idvar}])
                                String  send expression
remote_foreground( {server})    Number  bring Vim server to the foreground
remote_peek( {serverid} [, {retvar}])
                                Number  check for reply string
remote_read( {serverid})        String  read reply string
remote_send( {server}, {string} [, {idvar}])
                                String  send key sequence
remove( {list}, {idx} [, {end}])  any   remove items {idx}-{end} from {list}
remove( {dict}, {key})          any     remove entry {key} from {dict}
rename( {from}, {to})           Number  rename (move) file from {from} to {to}
repeat( {expr}, {count})        String  repeat {expr} {count} times
resolve( {filename})            String  get filename a shortcut points to
reverse( {list})                List        reverse {list} in-place
search( {pattern} [, {flags}])  Number  search for {pattern}
searchdecl({name} [, {global} [, {thisblock}]])
                                Number  search for variable declaration
searchpair( {start}, {middle}, {end} [, {flags} [, {skip} [, {stopline}]]])
                                Number  search for other end of start/end pair
searchpairpos( {start}, {middle}, {end} [, {flags} [, {skip} [, {stopline}]]])
                                List        search for other end of start/end pair
searchpos( {pattern} [, {flags} [, {stopline}]])
                                List        search for {pattern}
server2client( {clientid}, {string})
                                Number  send reply string
serverlist()                        String  get a list of available servers
setbufvar( {expr}, {varname}, {val})    set {varname} in buffer {expr} to {val}
setcmdpos( {pos})               Number  set cursor position in command-line
setline( {lnum}, {line})        Number  set line {lnum} to {line}
setloclist( {nr}, {list}[, {action}])
                                Number  modify location list using {list}
setpos( {expr}, {list})         none    set the {expr} position to {list}
setqflist( {list}[, {action}])  Number  modify quickfix list using {list}
setreg( {n}, {v}[, {opt}])      Number  set register to value and type
settabwinvar( {tabnr}, {winnr}, {varname}, {val})    set {varname} in window
                                        {winnr} in tab page {tabnr} to {val}
setwinvar( {nr}, {varname}, {val})      set {varname} in window {nr} to {val}
simplify( {filename})           String  simplify filename as much as possible
sort( {list} [, {func}])        List        sort {list}, using {func} to compare
soundfold( {word})              String  sound-fold {word}
spellbadword()                    String  badly spelled word at cursor
spellsuggest( {word} [, {max} [, {capital}]])
                                List        spelling suggestions
split( {expr} [, {pat} [, {keepempty}]])
                                List    make |List| from {pat} separated {expr}
str2nr( {expr} [, {base}])      Number  convert string to number
strftime( {format}[, {time}])   String  time in specified format
stridx( {haystack}, {needle}[, {start}])
                                Number  index of {needle} in {haystack}
string( {expr})                 String  String representation of {expr} value
strlen( {expr})                 Number  length of the String {expr}
strpart( {src}, {start}[, {len}])
                                String  {len} characters of {src} at {start}
strridx( {haystack}, {needle} [, {start}])
                                Number  last index of {needle} in {haystack}
strtrans( {expr})               String  translate string to make it printable
submatch( {nr})                 String  specific match in ":substitute"
substitute( {expr}, {pat}, {sub}, {flags})
                                String  all {pat} in {expr} replaced with {sub}
synID( {lnum}, {col}, {trans})  Number  syntax ID at {lnum} and {col}
synIDattr( {synID}, {what} [, {mode}])
                                String  attribute {what} of syntax ID {synID}
synIDtrans( {synID})            Number  translated syntax ID of {synID}
system( {expr} [, {input}])     String  output of shell command/filter {expr}
tabpagebuflist( [{arg}])        List        list of buffer numbers in tab page
tabpagenr( [{arg}])             Number  number of current or last tab page
tabpagewinnr( {tabarg}[, {arg}])
                                Number  number of current window in tab page
taglist( {expr})                List        list of tags matching {expr}
tagfiles()                    List    tags files used
tempname()                    String  name for a temporary file
tolower( {expr})                String  the String {expr} switched to lowercase
toupper( {expr})                String  the String {expr} switched to uppercase
tr( {src}, {fromstr}, {tostr})  String  translate chars of {src} in {fromstr}
                                        to chars in {tostr}
type( {name})                   Number  type of variable {name}
values( {dict})                 List        values in {dict}
virtcol( {expr})                Number  screen column of cursor or mark
visualmode( [expr])             String  last visual mode used
winbufnr( {nr})                 Number  buffer number of window {nr}
wincol()                        Number  window column of the cursor
winheight( {nr})                Number  height of window {nr}
winline()                      Number  window line of the cursor
winnr( [{expr}])                Number  number of current window
winrestcmd()                        String  returns command to restore window sizes
winrestview({dict})             None    restore view of current window
winsaveview()                      Dict    save view of current window
winwidth( {nr})                 Number  width of window {nr}
writefile({list}, {fname} [, {binary}])
                                Number  write list of lines to file {fname}


add({list}, {expr})                                     *add()*
                Append the item {expr} to |List| {list}.  Returns the
                resulting |List|.  Examples:
                     :let alist = add([1, 2, 3], item)
                     :call add(mylist, "woodstock")
                Note that when {expr} is a |List| it is appended as a single
                item.  Use |extend()| to concatenate |Lists|.
                Use |insert()| to add an item at another position.



append({lnum}, {expr})                                  *append()*
                When {expr} is a |List|: Append each item of the |List| as a
                text line below line {lnum} in the current buffer.
                Otherwise append {expr} as one text line below line {lnum} in
                the current buffer.
                {lnum} can be zero to insert a line before the first one.
                Returns 1 for failure ({lnum} out of range or out of memory),
                0 for success.  Example:
                     :let failed = append(line('$'), "# THE END")
                     :let failed = append(0, ["Chapter 1", "the beginning"])
 

                                                        *argc()*
argc()            The result is the number of files in the argument list of the
                current window.  See |arglist|.


                                                        *argidx()*
argidx()        The result is the current index in the argument list.  0 is
                the first file.  argc() - 1 is the last one.  See |arglist|.


                                                        *argv()*
argv([{nr}])    The result is the {nr}th file in the argument list of the
                current window.  See |arglist|.  "argv(0)" is the first one.
                Example:
     :let i = 0
     :while i < argc()
     :  let f = escape(argv(i), '. ')
     :  exe 'amenu Arg.' . f . ' :e ' . f . '<CR>'
     :  let i = i + 1
     :endwhile
                Without the {nr} argument a |List| with the whole |arglist| is
                returned.


                                                        *browse()*
browse({save}, {title}, {initdir}, {default})
                Put up a file requester.  This only works when "has("browse")"
                returns non-zero (only in some GUI versions).
                The input fields are:
                    {save}      when non-zero, select file to write
                    {title}     title for the requester
                    {initdir}   directory to start browsing in
                    {default}   default file name
                When the "Cancel" button is hit, something went wrong, or
                browsing is not possible, an empty string is returned.


                                                        *browsedir()*
browsedir({title}, {initdir})
                Put up a directory requester.  This only works when
                "has("browse")" returns non-zero (only in some GUI versions).
                On systems where a directory browser is not supported a file
                browser is used.  In that case: select a file in the directory
                to be used.
                The input fields are:
                    {title}     title for the requester
                    {initdir}   directory to start browsing in
                When the "Cancel" button is hit, something went wrong, or
                browsing is not possible, an empty string is returned.


bufexists({expr})                                       *bufexists()*
                The result is a Number, which is non-zero if a buffer called
                {expr} exists.
                If the {expr} argument is a number, buffer numbers are used.
                If the {expr} argument is a string it must match a buffer name
                exactly.  The name can be:
                - Relative to the current directory.
                - A full path.
                - The name of a buffer with 'filetype' set to "nofile".
                - A URL name.
                Unlisted buffers will be found.
                Note that help files are listed by their short name in the
                output of |:buffers|, but bufexists() requires using their
                long name to be able to find them.
                Use "bufexists(0)" to test for the existence of an alternate
                file name.

                                                        *buffer_exists()*
                Obsolete name: buffer_exists().


buflisted({expr})                                       *buflisted()*
                The result is a Number, which is non-zero if a buffer called
                {expr} exists and is listed (has the 'buflisted' option set).
                The {expr} argument is used like with |bufexists()|.


bufloaded({expr})                                       *bufloaded()*
                The result is a Number, which is non-zero if a buffer called
                {expr} exists and is loaded (shown in a window or hidden).
                The {expr} argument is used like with |bufexists()|.


bufname({expr})                                         *bufname()*
                The result is the name of a buffer, as it is displayed by the
                ":ls" command.
                If {expr} is a Number, that buffer number's name is given.
                Number zero is the alternate buffer for the current window.
                If {expr} is a String, it is used as a |file-pattern| to match
                with the buffer names.  This is always done like 'magic' is
                set and 'cpoptions' is empty.  When there is more than one
                match an empty string is returned.
                "" or "%" can be used for the current buffer, "#" for the
                alternate buffer.
                A full match is preferred, otherwise a match at the start, end
                or middle of the buffer name is accepted.
                Listed buffers are found first.  If there is a single match
                with a listed buffer, that one is returned.  Next unlisted
                buffers are searched for.
                If the {expr} is a String, but you want to use it as a buffer
                number, force it to be a Number by adding zero to it:
                     :echo bufname("3" + 0)
                If the buffer doesn't exist, or doesn't have a name, an empty
                string is returned.
     bufname("#")            alternate buffer name
     bufname(3)              name of buffer 3
     bufname("%")            name of current buffer
     bufname("file2")        name of buffer where "file2" matches.

                                                        *buffer_name()*
                Obsolete name: buffer_name().


                                                        *bufnr()*
bufnr({expr} [, {create}])
                The result is the number of a buffer, as it is displayed by
                the ":ls" command.  For the use of {expr}, see |bufname()|
                above.
                If the buffer doesn't exist, -1 is returned.  Or, if the
                {create} argument is present and not zero, a new, unlisted,
                buffer is created and its number is returned.
                bufnr("$") is the last buffer:
     :let last_buffer = bufnr("$")
                The result is a Number, which is the highest buffer number
                of existing buffers.  Note that not all buffers with a smaller
                number necessarily exist, because ":bwipeout" may have removed
                them.  Use bufexists() to test for the existence of a buffer.

                                                        *buffer_number()*
                Obsolete name: buffer_number().

                                                        *last_buffer_nr()*
                Obsolete name for bufnr("$"): last_buffer_nr().


bufwinnr({expr})                                        *bufwinnr()*
                The result is a Number, which is the number of the first
                window associated with buffer {expr}.  For the use of {expr},
                see |bufname()| above.  If buffer {expr} doesn't exist or
                there is no such window, -1 is returned.  Example:

     echo "A window containing buffer 1 is " . (bufwinnr(1))

                The number can be used with |CTRL-W_w| and ":wincmd w"
                |:wincmd|.



byte2line({byte})                                       *byte2line()*
                Return the line number that contains the character at byte
                count {byte} in the current buffer.  This includes the
                end-of-line character, depending on the 'fileformat' option
                for the current buffer.  The first character has byte count
                one.
                Also see |line2byte()|, |go| and |:goto|.
                {not available when compiled without the |+byte_offset|
                feature}


byteidx({expr}, {nr})                                   *byteidx()*
                Return byte index of the {nr}'th character in the string
                {expr}.  Use zero for the first character, it returns zero.
                This function is only useful when there are multibyte
                characters, otherwise the returned value is equal to {nr}.
                Composing characters are counted as a separate character.
                Example :
                     echo matchstr(str, ".", byteidx(str, 3))
                will display the fourth character.  Another way to do the
                same:
                     let s = strpart(str, byteidx(str, 3))
                     echo strpart(s, 0, byteidx(s, 1))
                If there are less than {nr} characters -1 is returned.
                If there are exactly {nr} characters the length of the string
                is returned.


call({func}, {arglist} [, {dict}])                 *call()* *E699*
                Call function {func} with the items in |List| {arglist} as
                arguments.
                {func} can either be a |Funcref| or the name of a function.
                a:firstline and a:lastline are set to the cursor line.
                Returns the return value of the called function.
                {dict} is for functions with the "dict" attribute.  It will be
                used to set the local variable "self". |Dictionary-function|


changenr()                                            *changenr()*
                Return the number of the most recent change.  This is the same
                number as what is displayed with |:undolist| and can be used
                with the |:undo| command.
                When a change was made it is the number of that change.  After
                redo it is the number of the redone change.  After undo it is
                one less than the number of the undone change.


char2nr({expr})                                         *char2nr()*
                Return number value of the first char in {expr}.  Examples:
                     char2nr(" ")            returns 32
                     char2nr("ABC")          returns 65
                The current 'encoding' is used.  Example for "utf-8":
                     char2nr("?")            returns 225
                     char2nr("?"[0])         returns 195
                nr2char() does the opposite.


cindent({lnum})                                         *cindent()*
                Get the amount of indent for line {lnum} according the C
                indenting rules, as with 'cindent'.
                The indent is counted in spaces, the value of 'tabstop' is
                relevant.  {lnum} is used just like in |getline()|.
                When {lnum} is invalid or Vim was not compiled the |+cindent|
                feature, -1 is returned.
                See |C-indenting|.


                                                        *col()*
col({expr})     The result is a Number, which is the byte index of the column
                position given with {expr}.  The accepted positions are:
                    .       the cursor position
                    $       the end of the cursor line (the result is the
                            number of characters in the cursor line plus one)
                    'x      position of mark x (if the mark is not set, 0 is
                            returned)
                To get the line number use |col()|.  To get both use
                |getpos()|.
                For the screen column position use |virtcol()|.
                Note that only marks in the current file can be used.
                Examples:
                     col(".")                column of cursor
                     col("$")                length of cursor line plus one
                     col("'t")               column of mark t
                     col("'" . markname)     column of mark markname
                The first column is 1.  0 is returned for an error.
                For the cursor position, when 'virtualedit' is active, the
                column is one higher if the cursor is after the end of the
                line.  This can be used to obtain the column in Insert mode:
                     :imap <F2> <C-O>:let save_ve = &ve<CR>
                             \<C-O>:set ve=all<CR>
                             \<C-O>:echo col(".") . "\n" <Bar>
                             \let &ve = save_ve<CR>
 


complete({startcol}, {matches})                 *complete()* *E785*
                Set the matches for Insert mode completion.
                Can only be used in Insert mode.  You need to use a mapping
                with an expression argument |:map-<expr>| or CTRL-R =
                |i_CTRL-R|.  It does not work after CTRL-O.
                {startcol} is the byte offset in the line where the completed
                text start.  The text up to the cursor is the original text
                that will be replaced by the matches.  Use col('.') for an
                empty string.  "col('.') - 1" will replace one character by a
                match.
                {matches} must be a |List|.  Each |List| item is one match.
                See |complete-items| for the kind of items that are possible.
                Note that the after calling this function you need to avoid
                inserting anything that would completion to stop.
                The match can be selected with CTRL-N and CTRL-P as usual with
                Insert mode completion.  The popup menu will appear if
                specified, see |ins-completion-menu|.
                Example:
     inoremap <expr> <F5> ListMonths()

     func! ListMonths()
       call complete(col('.'), ['January', 'February', 'March',
             \ 'April', 'May', 'June', 'July', 'August', 'September',
             \ 'October', 'November', 'December'])
       return ''
     endfunc
                This isn't very useful, but it shows how it works.  Note that
                an empty string is returned to avoid a zero being inserted.


complete_add({expr})                            *complete_add()*
                Add {expr} to the list of matches.  Only to be used by the
                function specified with the 'completefunc' option.
                Returns 0 for failure (empty string or out of memory),
                1 when the match was added, 2 when the match was already in
                the list.
                See |complete-functions| for an explanation of {expr}.  It is
                the same as one item in the list that 'omnifunc' would return.


complete_check()                                *complete_check()*
                Check for a key typed while looking for completion matches.
                This is to be used when looking for matches takes some time.
                Returns non-zero when searching for matches is to be aborted,
                zero otherwise.
                Only to be used by the function specified with the
                'completefunc' option.


                                                *confirm()*
confirm({msg} [, {choices} [, {default} [, {type}]]])
                Confirm() offers the user a dialog, from which a choice can be
                made.  It returns the number of the choice.  For the first
                choice this is 1.
                Note: confirm() is only supported when compiled with dialog
                support, see |+dialog_con| and |+dialog_gui|.
                {msg} is displayed in a |dialog| with {choices} as the
                alternatives.  When {choices} is missing or empty, "&OK" is
                used (and translated).
                {msg} is a String, use '\n' to include a newline.  Only on
                some systems the string is wrapped when it doesn't fit.
                {choices} is a String, with the individual choices separated
                by '\n', e.g.
                     confirm("Save changes?", "&Yes\n&No\n&Cancel")
                The letter after the '&' is the shortcut key for that choice.
                Thus you can type 'c' to select "Cancel".  The shortcut does
                not need to be the first letter:
                     confirm("file has been modified", "&Save\nSave &All")
                For the console, the first letter of each choice is used as
                the default shortcut key.
                The optional {default} argument is the number of the choice
                that is made if the user hits <CR>.  Use 1 to make the first
                choice the default one.  Use 0 to not set a default.  If
                {default} is omitted, 1 is used.
                The optional {type} argument gives the type of dialog.  This
                is only used for the icon of the Win32 GUI.  It can be one of
                these values: "Error", "Question", "Info", "Warning" or
                "Generic".  Only the first character is relevant.  When {type}
                is omitted, "Generic" is used.
                If the user aborts the dialog by pressing <Esc>, CTRL-C,
                or another valid interrupt key, confirm() returns 0.

                An example:
   :let choice = confirm("What do you want?", "&Apples\n&Oranges\n&Bananas", 2)
   :if choice == 0
   : echo "make up your mind!"
   :elseif choice == 3
   : echo "tasteful"
   :else
   : echo "I prefer bananas myself."
   :endif
                In a GUI dialog, buttons are used.  The layout of the buttons
                depends on the 'v' flag in 'guioptions'.  If it is included,
                the buttons are always put vertically.  Otherwise,  confirm()
                tries to put the buttons in one horizontal line.  If they
                don't fit, a vertical layout is used anyway.  For some systems
                the horizontal layout is always used.


                                                        *copy()*
copy({expr})    Make a copy of {expr}.  For Numbers and Strings this isn't
                different from using {expr} directly.
                When {expr} is a |List| a shallow copy is created.  This means
                that the original |List| can be changed without changing the
                copy, and vise versa.  But the items are identical, thus
                changing an item changes the contents of both |Lists|.  Also
                see |deepcopy()|.


count({comp}, {expr} [, {ic} [, {start}]])                      *count()*
                Return the number of times an item with value {expr} appears
                in |List| or |Dictionary| {comp}.
                If {start} is given then start with the item with this index.
                {start} can only be used with a |List|.
                When {ic} is given and it's non-zero then case is ignored.



                                                        *cscope_connection()*
cscope_connection([{num} , {dbpath} [, {prepend}]])
                Checks for the existence of a |cscope| connection.  If no
                parameters are specified, then the function returns:
                        0, if cscope was not available (not compiled in), or
                           if there are no cscope connections;
                        1, if there is at least one cscope connection.

                If parameters are specified, then the value of {num}
                determines how existence of a cscope connection is checked:

                {num}   Description of existence check
                -----   ------------------------------
                0       Same as no parameters (e.g., "cscope_connection()").
                1       Ignore {prepend}, and use partial string matches for
                        {dbpath}.
                2       Ignore {prepend}, and use exact string matches for
                        {dbpath}.
                3       Use {prepend}, use partial string matches for both
                        {dbpath} and {prepend}.
                4       Use {prepend}, use exact string matches for both
                        {dbpath} and {prepend}.

                Note: All string comparisons are case sensitive!

                Examples.  Suppose we had the following (from ":cs show"):

  # pid    database name                     prepend path
  0 27664  cscope.out                                /usr/local
 
                Invocation                                      Return Val 
                ----------                                      ----------
             cscope_connection()                                     1
             cscope_connection(1, "out")                             1
             cscope_connection(2, "out")                             0
             cscope_connection(3, "out")                             0
             cscope_connection(3, "out", "local")                    1
             cscope_connection(4, "out")                             0
             cscope_connection(4, "out", "local")                    0
             cscope_connection(4, "cscope.out", "/usr/local")        1
 

cursor({lnum}, {col} [, {off}])                         *cursor()*
cursor({list})
                Positions the cursor at the column {col} in the line {lnum}.
                The first column is one.
                When there is one argument {list} this is used as a |List|
                with two or three items {lnum}, {col} and {off}.  This is like
                the return value of |getpos()|, but without the first item.
                Does not change the jumplist.
                If {lnum} is greater than the number of lines in the buffer,
                the cursor will be positioned at the last line in the buffer.
                If {lnum} is zero, the cursor will stay in the current line.
                If {col} is greater than the number of bytes in the line,
                the cursor will be positioned at the last character in the
                line.
                If {col} is zero, the cursor will stay in the current column.
                When 'virtualedit' is used {off} specifies the offset in
                screen columns from the start of the character.  E.g., a
                position within a Tab or after the last character.



deepcopy({expr}[, {noref}])                             *deepcopy()* *E698*
                Make a copy of {expr}.  For Numbers and Strings this isn't
                different from using {expr} directly.
                When {expr} is a |List| a full copy is created.  This means
                that the original |List| can be changed without changing the
                copy, and vise versa.  When an item is a |List|, a copy for it
                is made, recursively.  Thus changing an item in the copy does
                not change the contents of the original |List|.
                When {noref} is omitted or zero a contained |List| or
                |Dictionary| is only copied once.  All references point to
                this single copy.  With {noref} set to 1 every occurrence of a
                |List| or |Dictionary| results in a new copy.  This also means
                that a cyclic reference causes deepcopy() to fail.

                                                                *E724*
                Nesting is possible up to 100 levels.  When there is an item
                that refers back to a higher level making a deep copy with
                {noref} set to 1 will fail.
                Also see |copy()|.


delete({fname})                                                 *delete()*
                Deletes the file by the name {fname}.  The result is a Number,
                which is 0 if the file was deleted successfully, and non-zero
                when the deletion failed.
                Use |remove()| to delete an item from a |List|.


                                                        *did_filetype()*
did_filetype()    Returns non-zero when autocommands are being executed and the
                FileType event has been triggered at least once.  Can be used
                to avoid triggering the FileType event again in the scripts
                that detect the file type. |FileType|
                When editing another file, the counter is reset, thus this
                really checks if the FileType event has been triggered for the
                current buffer.  This allows an autocommand that starts
                editing another buffer to set 'filetype' and load a syntax
                file.


diff_filler({lnum})                                     *diff_filler()*
                Returns the number of filler lines above line {lnum}.
                These are the lines that were inserted at this point in
                another diff'ed window.  These filler lines are shown in the
                display but don't exist in the buffer.
                {lnum} is used like with |getline()|.  Thus "." is the current
                line, "'m" mark m, etc.
                Returns 0 if the current window is not in diff mode.


diff_hlID({lnum}, {col})                                *diff_hlID()*
                Returns the highlight ID for diff mode at line {lnum} column
                {col} (byte index).  When the current line does not have a
                diff change zero is returned.
                {lnum} is used like with |getline()|.  Thus "." is the current
                line, "'m" mark m, etc.
                {col} is 1 for the leftmost column, {lnum} is 1 for the first
                line.
                The highlight ID can be used with |synIDattr()| to obtain
                syntax information about the highlighting.


empty({expr})                                           *empty()*
                Return the Number 1 if {expr} is empty, zero otherwise.
                A |List| or |Dictionary| is empty when it does not have any
                items.  A Number is empty when its value is zero.
                For a long |List| this is much faster then comparing the
                length with zero.


escape({string}, {chars})                               *escape()*
                Escape the characters in {chars} that occur in {string} with a
                backslash.  Example:
                     :echo escape('c:\program files\vim', ' \')
                results in:
                     c:\\program\ files\\vim


                                                        *eval()*
eval({string})  Evaluate {string} and return the result.  Especially useful to
                turn the result of |string()| back into the original value.
                This works for Numbers, Strings and composites of them.
                Also works for |Funcref|s that refer to existing functions.


eventhandler()                                            *eventhandler()*
                Returns 1 when inside an event handler.  That is that Vim got
                interrupted while waiting for the user to type a character,
                e.g., when dropping a file on Vim.  This means interactive
                commands cannot be used.  Otherwise zero is returned.


executable({expr})                                      *executable()*
                This function checks if an executable with the name {expr}
                exists.  {expr} must be the name of the program without any
                arguments.
                executable() uses the value of $PATH and/or the normal

                searchpath for programs.                *PATHEXT*
                On MS-DOS and MS-Windows the ".exe", ".bat", etc. can
                optionally be included.  Then the extensions in $PATHEXT are
                tried.  Thus if "foo.exe" does not exist, "foo.exe.bat" can be
                found.  If $PATHEXT is not set then ".exe;.com;.bat;.cmd" is
                used.  A dot by itself can be used in $PATHEXT to try using
                the name without an extension.  When 'shell' looks like a
                Unix shell, then the name is also tried without adding an
                extension.
                On MS-DOS and MS-Windows it only checks if the file exists and
                is not a directory, not if it's really executable.
                On MS-Windows an executable in the same directory as Vim is
                always found.  Since this directory is added to $PATH it
                should also work to execute it |win32-PATH|.
                The result is a Number:
                        1       exists
                        0       does not exist
                        -1      not implemented on this system


                                                        *exists()*
exists({expr})  The result is a Number, which is non-zero if {expr} is
                defined, zero otherwise.  The {expr} argument is a string,
                which contains one of these:
                        &option-name        Vim option (only checks if it exists,
                                        not if it really works)
                        +option-name    Vim option that works.
                        $ENVNAME        environment variable (could also be
                                        done by comparing with an empty
                                        string)
                        *funcname       built-in function (see |functions|)
                                        or user defined function (see
                                        |user-functions|).
                        varname         internal variable (see
                                        |internal-variables|).  Also works
                                        for |curly-braces-names|, |Dictionary|
                                        entries, |List| items, etc.  Beware
                                        that this may cause functions to be
                                        invoked cause an error message for an
                                        invalid expression.
                        :cmdname        Ex command: built-in command, user
                                        command or command modifier |:command|.
                                        Returns:
                                        1  for match with start of a command
                                        2  full match with a command
                                        3  matches several user commands
                                        To check for a supported command
                                        always check the return value to be 2.
                        :2match         The |:2match| command.
                        :3match         The |:3match| command.
                        #event          autocommand defined for this event
                        #event#pattern  autocommand defined for this event and
                                        pattern (the pattern is taken
                                        literally and compared to the
                                        autocommand patterns character by
                                        character)
                        #group          autocommand group exists
                        #group#event    autocommand defined for this group and
                                        event.
                        #group#event#pattern
                                        autocommand defined for this group,
                                        event and pattern.
                        ##event         autocommand for this event is
                                        supported.
                For checking for a supported feature use |has()|.

                Examples:
                     exists("&shortname")
                     exists("$HOSTNAME")
                     exists("*strftime")
                     exists("*s:MyFunc")
                     exists("bufcount")
                     exists(":Make")
                     exists("#CursorHold")
                     exists("#BufReadPre#*.gz")
                     exists("#filetypeindent")
                     exists("#filetypeindent#FileType")
                     exists("#filetypeindent#FileType#*")
                     exists("##ColorScheme")
                There must be no space between the symbol (&/$/*/#) and the
                name.
                There must be no extra characters after the name, although in
                a few cases this is ignored.  That may become more strict in
                the future, thus don't count on it!
                Working example:
                     exists(":make")
                NOT working example:
                     exists(":make install")

                Note that the argument must be a string, not the name of the
                variable itself.  For example:
                     exists(bufcount)
                This doesn't check for existence of the "bufcount" variable,
                but gets the value of "bufcount", and checks if that exists.


expand({expr} [, {flag}])                               *expand()*
                Expand wildcards and the following special keywords in {expr}.
                The result is a String.

                When there are several matches, they are separated by <NL>
                characters.  [Note: in version 5.0 a space was used, which
                caused problems when a file name contains a space]

                If the expansion fails, the result is an empty string.  A name
                for a non-existing file is not included.

                When {expr} starts with '%', '#' or '<', the expansion is done
                like for the |cmdline-special| variables with their associated
                modifiers.  Here is a short overview:

                        %               current file name
                        #               alternate file name
                        #n              alternate file name n
                        <cfile>          file name under the cursor
                        <afile>                autocmd file name
                        <abuf>          autocmd buffer number (as a String!)
                        <amatch>      autocmd matched name
                        <sfile>                sourced script file name
                        <cword>           word under the cursor
                        <cWORD>           WORD under the cursor
                        <client>  the {clientid} of the last received
                                        message |server2client()|
                Modifiers:
                        :p                expand to full path
                        :h                head (last path component removed)
                        :t         tail (last path component only)
                        :r         root (one extension removed)
                        :e                extension only

                Example:
                     :let &tags = expand("%:p:h") . "/tags"
                Note that when expanding a string that starts with '%', '#' or
                '<', any following text is ignored.  This does NOT work:
                     :let doesntwork = expand("%:h.bak")
                Use this:
                     :let doeswork = expand("%:h") . ".bak"
                Also note that expanding "<cfile>" and others only returns the
                referenced file name without further expansion.  If "<cfile>"
                is "~/.cshrc", you need to do another expand() to have the
                "~/" expanded into the path of the home directory:
                     :echo expand(expand("<cfile>"))
 
                There cannot be white space between the variables and the
                following modifier.  The |fnamemodify()| function can be used
                to modify normal file names.

                When using '%' or '#', and the current or alternate file name
                is not defined, an empty string is used.  Using "%:p" in a
                buffer with no name, results in the current directory, with a
                '/' added.

                When {expr} does not start with '%', '#' or '<', it is
                expanded like a file name is expanded on the command line.
                'suffixes' and 'wildignore' are used, unless the optional
                {flag} argument is given and it is non-zero.  Names for
                non-existing files are included.  The "**" item can be used to
                search in a directory tree.  For example, to find all "README"
                files in the current directory and below:
                     :echo expand("**/README")
 
                Expand() can also be used to expand variables and environment
                variables that are only known in a shell.  But this can be
                slow, because a shell must be started.  See |expr-env-expand|.
                The expanded variable is still handled like a list of file
                names.  When an environment variable cannot be expanded, it is
                left unchanged.  Thus ":echo expand('$FOOBAR')" results in
                "$FOOBAR".

                See |glob()| for finding existing files.  See |system()| for
                getting the raw output of an external command.


extend({expr1}, {expr2} [, {expr3}])                    *extend()*
                {expr1} and {expr2} must be both |Lists| or both
                |Dictionaries|.

                If they are |Lists|: Append {expr2} to {expr1}.
                If {expr3} is given insert the items of {expr2} before item
                {expr3} in {expr1}.  When {expr3} is zero insert before the
                first item.  When {expr3} is equal to len({expr1}) then
                {expr2} is appended.
                Examples:
                     :echo sort(extend(mylist, [7, 5]))
                     :call extend(mylist, [2, 3], 1)
                Use |add()| to concatenate one item to a list.  To concatenate
                two lists into a new list use the + operator:
                     :let newlist = [1, 2, 3] + [4, 5]
 
                If they are YXXYDictionaries|:
                Add all entries from {expr2} to {expr1}.
                If a key exists in both {expr1} and {expr2} then {expr3} is
                used to decide what to do:
                {expr3} = "keep": keep the value of {expr1}
                {expr3} = "force": use the value of {expr2}

                {expr3} = "error": give an error message              *E737*
                When {expr3} is omitted then "force" is assumed.

                {expr1} is changed when {expr2} is not empty.  If necessary
                make a copy of {expr1} first.
                {expr2} remains unchanged.
                Returns {expr1}.



feedkeys({string} [, {mode}])                           *feedkeys()*
                Characters in {string} are queued for processing as if they
                come from a mapping or were typed by user.  They are added to
                the end of the typeahead buffer, thus if a mapping is still
                being executed these characters come after them.
                The function does not wait for processing of keys contained in
                {string}.
                To include special keys into {string}, use double-quotes
                and "\..." notation |expr-quote|. For example,
                feedkeys("\<CR>") simulates pressing of the Enter key. But
                feedkeys('\<CR>') pushes 5 characters.
                If {mode} is absent, keys are remapped.
                {mode} is a String, which can contain these character flags:
                'm' Remap keys. This is default.
                'n'        Do not remap keys.
                't' Handle keys as if typed; otherwise they are handled as
                        if coming from a mapping.  This matters for undo,
                        opening folds, etc.
                Return value is always 0.


filereadable({file})                                    *filereadable()*
                The result is a Number, which is TRUE when a file with the
                name {file} exists, and can be read.  If {file} doesn't exist,
                or is a directory, the result is FALSE.  {file} is any
                expression, which is used as a String.

                                                        *file_readable()*
                Obsolete name: file_readable().



filter({expr}, {string})                                        *filter()*
                {expr} must be a |List| or a |Dictionary|.
                For each item in {expr} evaluate {string} and when the result
                is zero remove the item from the |List| or |Dictionary|.
                Inside {string} |v:val| has the value of the current item.
                For a |Dictionary| |v:key| has the key of the current item.
                Examples:
                     :call filter(mylist, 'v:val !~ "OLD"')
                Removes the items where "OLD" appears.
                     :call filter(mydict, 'v:key >= 8')
                Removes the items with a key below 8.
                     :call filter(var, 0)
                Removes all the items, thus clears the |List| or |Dictionary|.

                Note that {string} is the result of expression and is then
                used as an expression again.  Often it is good to use a
                |literal-string| to avoid having to double backslashes.

                The operation is done in-place.  If you want a |List| or
                |Dictionary| to remain unmodified make a copy first:
                     :let l = filter(copy(mylist), 'v:val =~ "KEEP"')

                Returns {expr}, the |List| or |Dictionary| that was filtered.
                When an error is encountered while evaluating {string} no
                further items in {expr} are processed.



finddir({name}[, {path}[, {count}]])                            *finddir()*
                Find directory {name} in {path}.  Returns the path of the
                first found match.  When the found directory is below the
                current directory a relative path is returned.  Otherwise a
                full path is returned.
                If {path} is omitted or empty then 'path' is used.
                If the optional {count} is given, find {count}'s occurrence of
                {name} in {path} instead of the first one.
                When {count} is negative return all the matches in a |List|.
                This is quite similar to the ex-command |:find|.
                {only available when compiled with the +file_in_path feature}


findfile({name}[, {path}[, {count}]])                           *findfile()*
                Just like |finddir()|, but find a file instead of a directory.
                Uses 'suffixesadd'.
                Example:
                     :echo findfile("tags.vim", ".;")
                Searches from the current directory upwards until it finds
                the file "tags.vim".


filewritable({file})                                    *filewritable()*
                The result is a Number, which is 1 when a file with the
                name {file} exists, and can be written.  If {file} doesn't
                exist, or is not writable, the result is 0.  If (file) is a
                directory, and we can write to it, the result is 2.


fnamemodify({fname}, {mods})                            *fnamemodify()*
                Modify file name {fname} according to {mods}.  {mods} is a
                string of characters like it is used for file names on the
                command line.  See |filename-modifiers|.
                Example:
                     :echo fnamemodify("main.c", ":p:h")
                results in:
                     /home/mool/vim/vim/src
                Note: Environment variables and "~" don't work in {fname}, use
                |expand()| first then.


foldclosed({lnum})                                      *foldclosed()*
                The result is a Number.  If the line {lnum} is in a closed
                fold, the result is the number of the first line in that fold.
                If the line {lnum} is not in a closed fold, -1 is returned.


foldclosedend({lnum})                                   *foldclosedend()*
                The result is a Number.  If the line {lnum} is in a closed
                fold, the result is the number of the last line in that fold.
                If the line {lnum} is not in a closed fold, -1 is returned.


foldlevel({lnum})                                       *foldlevel()*
                The result is a Number, which is the foldlevel of line {lnum}
                in the current buffer.  For nested folds the deepest level is
                returned.  If there is no fold at line {lnum}, zero is
                returned.  It doesn't matter if the folds are open or closed.
                When used while updating folds (from 'foldexpr') -1 is
                returned for lines where folds are still to be updated and the
                foldlevel is unknown.  As a special case the level of the
                previous line is usually available.


                                                        *foldtext()*
foldtext()    Returns a String, to be displayed for a closed fold.  This is
                the default function used for the 'foldtext' option and should
                only be called from evaluating 'foldtext'.  It uses the
                |v:foldstart|, |v:foldend| and |v:folddashes| variables.
                The returned string looks like this:
                     +-- 45 lines: abcdef
                The number of dashes depends on the foldlevel.  The "45" is
                the number of lines in the fold.  "abcdef" is the text in the
                first non-blank line of the fold.  Leading white space, "//"
                or "/*" and the text from the 'foldmarker' and 'commentstring'
                options is removed.
                {not available when compiled without the |+folding| feature}


foldtextresult({lnum})                                  *foldtextresult()*
                Returns the text that is displayed for the closed fold at line
                {lnum}.  Evaluates 'foldtext' in the appropriate context.
                When there is no closed fold at {lnum} an empty string is
                returned.
                {lnum} is used like with |getline()|.  Thus "." is the current
                line, "'m" mark m, etc.
                Useful when exporting folded text, e.g., to HTML.
                {not available when compiled without the |+folding| feature}


                                                        *foreground()*
foreground()        Move the Vim window to the foreground.  Useful when sent from
                a client to a Vim server. |remote_send()|
                On Win32 systems this might not work, the OS does not always
                allow a window to bring itself to the foreground.  Use
                |remote_foreground()| instead.
                {only in the Win32, Athena, Motif and GTK GUI versions and the
                Win32 console version}



function({name})                                        *function()* *E700*
                Return a |Funcref| variable that refers to function {name}.
                {name} can be a user defined function or an internal function.



garbagecollect()                                        *garbagecollect()*
                Cleanup unused |Lists| and |Dictionaries| that have circular
                references.  There is hardly ever a need to invoke this
                function, as it is automatically done when Vim runs out of
                memory or is waiting for the user to press a key after
                'updatetime'.  Items without circular references are always
                freed when they become unused.
                This is useful if you have deleted a very big |List| and/or
                |Dictionary| with circular references in a script that runs
                for a long time.


get({list}, {idx} [, {default}])                        *get()*
                Get item {idx} from |List| {list}.  When this item is not
                available return {default}.  Return zero when {default} is
                omitted.
get({dict}, {key} [, {default}])
                Get item with key {key} from |Dictionary| {dict}.  When this
                item is not available return {default}.  Return zero when
                {default} is omitted.


                                                        *getbufline()*
getbufline({expr}, {lnum} [, {end}])
                Return a |List| with the lines starting from {lnum} to {end}
                (inclusive) in the buffer {expr}.  If {end} is omitted, a
                |List| with only the line {lnum} is returned.

                For the use of {expr}, see |bufname()| above.

                For {lnum} and {end} "$" can be used for the last line of the
                buffer.  Otherwise a number must be used.

                When {lnum} is smaller than 1 or bigger than the number of
                lines in the buffer, an empty |List| is returned.

                When {end} is greater than the number of lines in the buffer,
                it is treated as {end} is set to the number of lines in the
                buffer.  When {end} is before {lnum} an empty |List| is
                returned.

                This function works only for loaded buffers.  For unloaded and
                non-existing buffers, an empty |List| is returned.

                Example:
                     :let lines = getbufline(bufnr("myfile"), 1, "$")


getbufvar({expr}, {varname})                            *getbufvar()*
                The result is the value of option or local buffer variable
                {varname} in buffer {expr}.  Note that the name without "b:"
                must be used.
                This also works for a global or buffer-local option, but it
                doesn't work for a global variable, window-local variable or
                window-local option.
                For the use of {expr}, see |bufname()| above.
                When the buffer or variable doesn't exist an empty string is
                returned, there is no error message.
                Examples:
                     :let bufmodified = getbufvar(1, "&mod")
                     :echo "todo myvar = " . getbufvar("todo", "myvar")
 

getchar([expr])                                         *getchar()*
                Get a single character from the user or input stream.
                If [expr] is omitted, wait until a character is available.
                If [expr] is 0, only get a character when one is available.
                        Return zero otherwise.
                If [expr] is 1, only check if a character is available, it is
                        not consumed.  Return zero if no character available.

                Without {expr} and when {expr} is 0 a whole character or
                special key is returned.  If it is an 8-bit character, the
                result is a number.  Use nr2char() to convert it to a String.
                Otherwise a String is returned with the encoded character.
                For a special key it's a sequence of bytes starting with 0x80
                (decimal: 128).  This is the same value as the string
                "\<Key>", e.g., "\<Left>".  The returned value is also a
                String when a modifier (shift, control, alt) was used that is
                not included in the character.

                When {expr} is 1 only the first byte is returned.  For a
                one-byte character it is the character itself as a number.
                Use nr2char() to convert it to a String.

                There is no prompt, you will somehow have to make clear to the
                user that a character has to be typed.
                There is no mapping for the character.
                Key codes are replaced, thus when the user presses the <Del>
                key you get the code for the <Del> key, not the raw character
                sequence.  Examples:
                     getchar() == "\<Del>"
                     getchar() == "\<S-Left>"
                This example redefines "f" to ignore case:
                     :nmap f :call FindChar()<CR>
                     :function FindChar()
                     :  let c = nr2char(getchar())
                     :  while col('.') < col('$') - 1
                     :    normal l
                     :    if getline('.')[col('.') - 1] ==? c
                     :      break
                     :    endif
                     :  endwhile
                     :endfunction


getcharmod()                                                *getcharmod()*
                The result is a Number which is the state of the modifiers for
                the last obtained character with getchar() or in another way.
                These values are added together:
                        2       shift
                        4       control
                        8       alt (meta)
                        16      mouse double click
                        32      mouse triple click
                        64      mouse quadruple click
                        128     Macintosh only: command
                Only the modifiers that have not been included in the
                character itself are obtained.  Thus Shift-a results in "A"
                with no modifier.


getcmdline()                                                *getcmdline()*
                Return the current command-line.  Only works when the command
                line is being edited, thus requires use of |c_CTRL-\_e| or
                |c_CTRL-R_=|.
                Example:
                     :cmap <F7> <C-\>eescape(getcmdline(), ' \')<CR>
                Also see |getcmdtype()|, |getcmdpos()| and |setcmdpos()|.


getcmdpos()                                          *getcmdpos()*
                Return the position of the cursor in the command line as a
                byte count.  The first column is 1.
                Only works when editing the command line, thus requires use of
                |c_CTRL-\_e| or |c_CTRL-R_=|.  Returns 0 otherwise.
                Also see |getcmdtype()|, |setcmdpos()| and |getcmdline()|.


getcmdtype()                                                *getcmdtype()*
                Return the current command-line type. Possible return values
                are:
                    :   normal Ex command
                    >    debug mode command |debug-mode|
                    /   forward search command
                    ?   backward search command
                    @   |input()| command
                    -   |:insert| or |:append| command
                Only works when editing the command line, thus requires use of
                |c_CTRL-\_e| or |c_CTRL-R_=|.  Returns an empty string
                otherwise.
                Also see |getcmdpos()|, |setcmdpos()| and |getcmdline()|.


                                                        *getcwd()*
getcwd()        The result is a String, which is the name of the current
                working directory.


getfsize({fname})                                       *getfsize()*
                The result is a Number, which is the size in bytes of the
                given file {fname}.
                If {fname} is a directory, 0 is returned.
                If the file {fname} can't be found, -1 is returned.


getfontname([{name}])                                   *getfontname()*
                Without an argument returns the name of the normal font being
                used.  Like what is used for the Normal highlight group
                |hl-Normal|.
                With an argument a check is done whether {name} is a valid
                font name.  If not then an empty string is returned.
                Otherwise the actual font name is returned, or {name} if the
                GUI does not support obtaining the real name.
                Only works when the GUI is running, thus not in your vimrc or
                gvimrc file.  Use the |GUIEnter| autocommand to use this
                function just after the GUI has started.
                Note that the GTK 2 GUI accepts any font name, thus checking
                for a valid name does not work.


getfperm({fname})                                       *getfperm()*
                The result is a String, which is the read, write, and execute
                permissions of the given file {fname}.
                If {fname} does not exist or its directory cannot be read, an
                empty string is returned.
                The result is of the form "rwxrwxrwx", where each group of
                "rwx" flags represent, in turn, the permissions of the owner
                of the file, the group the file belongs to, and other users.
                If a user does not have a given permission the flag for this
                is replaced with the string "-".  Example:
                     :echo getfperm("/etc/passwd")
                This will hopefully (from a security point of view) display
                the string "rw-r--r--" or even "rw-------".


getftime({fname})                                       *getftime()*
                The result is a Number, which is the last modification time of
                the given file {fname}.  The value is measured as seconds
                since 1st Jan 1970, and may be passed to strftime().  See also
                |localtime()| and |strftime()|.
                If the file {fname} can't be found -1 is returned.


getftype({fname})                                       *getftype()*
                The result is a String, which is a description of the kind of
                file of the given file {fname}.
                If {fname} does not exist an empty string is returned.
                Here is a table over different kinds of files and their
                results:
                        Normal file             "file"
                        Directory               "dir"
                        Symbolic link           "link"
                        Block device            "bdev"
                        Character device        "cdev"
                        Socket                  "socket"
                        FIFO                    "fifo"
                        All other               "other"
                Example:
                     getftype("/home")
                Note that a type such as "link" will only be returned on
                systems that support it.  On some systems only "dir" and
                "file" are returned.


                                                        *getline()*
getline({lnum} [, {end}])
                Without {end} the result is a String, which is line {lnum}
                from the current buffer.  Example:
                     getline(1)
                When {lnum} is a String that doesn't start with a
                digit, line() is called to translate the String into a Number.
                To get the line under the cursor:
                     getline(".")
                When {lnum} is smaller than 1 or bigger than the number of
                lines in the buffer, an empty string is returned.

                When {end} is given the result is a |List| where each item is
                a line from the current buffer in the range {lnum} to {end},
                including line {end}.
                {end} is used in the same way as {lnum}.
                Non-existing lines are silently omitted.
                When {end} is before {lnum} an empty |List| is returned.
                Example:
                     :let start = line('.')
                     :let end = search("^$") - 1
                     :let lines = getline(start, end)


getloclist({nr})                                        *getloclist()*
                Returns a list with all the entries in the location list for
                window {nr}. When {nr} is zero the current window is used.
                For a location list window, the displayed location list is
                returned.  For an invalid window number {nr}, an empty list is
                returned. Otherwise, same as getqflist().


getqflist()                                          *getqflist()*
                Returns a list with all the current quickfix errors.  Each
                list item is a dictionary with these entries:
                        bufnr   number of buffer that has the file name, use
                                bufname() to get the name
                        lnum    line number in the buffer (first line is 1)
                        col     column number (first column is 1)
                        vcol    non-zero: "col" is visual column
                                zero: "col" is byte index
                        nr      error number
                        text    description of the error
                        type    type of the error, 'E', '1', etc.
                        valid   non-zero: recognized error message

                When there is no error list or it's empty an empty list is
                returned.

                Useful application: Find pattern matches in multiple files and
                do something with them:
                     :vimgrep /theword/jg *.c
                     :for d in getqflist()
                     :   echo bufname(d.bufnr) ':' d.lnum '=' d.text
                     :endfor



getreg([{regname} [, 1]])                               *getreg()*
                The result is a String, which is the contents of register
                {regname}.  Example:
                     :let cliptext = getreg('*')
                getreg('=') returns the last evaluated value of the expression
                register.  (For use in maps.)
                getreg('=', 1) returns the expression itself, so that it can
                be restored with |setreg()|.  For other registers the extra
                argument is ignored, thus you can always give it.
                If {regname} is not specified, |v:register| is used.



getregtype([{regname}])                                 *getregtype()*
                The result is a String, which is type of register {regname}.
                The value will be one of:
                    "v"                   for |characterwise| text
                    "V"                   for |linewise| text
                    "<CTRL-V>{width}"   for |blockwise-visual| text
                    0                   for an empty or unknown register
                <CTRL-V> is one character with value 0x16.
                If {regname} is not specified, |v:register| is used.


gettabwinvar({tabnr}, {winnr}, {varname})               *gettabwinvar()*
                Get the value of an option or local window variable {varname}
                in window {winnr} in tab page {tabnr}.
                Tabs are numbered starting with one.  For the current tabpage
                use |getwinvar()|.
                When {winnr} is zero the current window is used.
                This also works for a global option, buffer-local option and
                window-local option, but it doesn't work for a global variable
                or buffer-local variable.
                Note that the name without "w:" must be used.
                Examples:
                     :let list_is_on = gettabwinvar(1, 2, '&list')
                     :echo "myvar = " . gettabwinvar(3, 1, 'myvar')

                                                     *getwinposx()*
getwinposx()        The result is a Number, which is the X coordinate in pixels of
                the left hand side of the GUI Vim window.  The result will be
                -1 if the information is not available.


                                                        *getwinposy()*
getwinposy()        The result is a Number, which is the Y coordinate in pixels of
                the top of the GUI Vim window.  The result will be -1 if the
                information is not available.


getwinvar({winnr}, {varname})                           *getwinvar()*
                Like |gettabwinvar()| for the current tabpage.
                Examples:
                     :let list_is_on = getwinvar(2, '&list')
                     :echo "myvar = " . getwinvar(1, 'myvar')
 

                                                        *glob()*
glob({expr})    Expand the file wildcards in {expr}.  The result is a String.
                When there are several matches, they are separated by <NL>
                characters.
                If the expansion fails, the result is an empty string.
                A name for a non-existing file is not included.

                For most systems backticks can be used to get files names from
                any external command.  Example:
                     :let tagfiles = glob("`find . -name tags -print`")
                     :let &tags = substitute(tagfiles, "\n", ",", "g")
                The result of the program inside the backticks should be one
                item per line.  Spaces inside an item are allowed.

                See |expand()| for expanding special Vim variables.  See
                |system()| for getting the raw output of an external command.


globpath({path}, {expr})                                *globpath()*
                Perform glob() on all directories in {path} and concatenate
                the results.  Example:
                     :echo globpath(&rtp, "syntax/c.vim")
                {path} is a comma-separated list of directory names.  Each
                directory name is prepended to {expr} and expanded like with
                glob().  A path separator is inserted when needed.
                To add a comma inside a directory name escape it with a
                backslash.  Note that on MS-Windows a directory may have a
                trailing backslash, remove it if you put a comma after it.
                If the expansion fails for one of the directories, there is no
                error message.
                The 'wildignore' option applies: Names matching one of the
                patterns in 'wildignore' will be skipped.

                The "**" item can be used to search in a directory tree.
                For example, to find all "README.txt" files in the directories
                in 'runtimepath' and below:
                     :echo globpath(&rtp, "**/README.txt")
 

                                                        *has()*
has({feature})  The result is a Number, which is 1 if the feature {feature} is
                supported, zero otherwise.  The {feature} argument is a
                string.  See |feature-list| below.
                Also see |exists()|.



has_key({dict}, {key})                                  *has_key()*
                The result is a Number, which is 1 if |Dictionary| {dict} has
                an entry with key {key}.  Zero otherwise.



hasmapto({what} [, {mode} [, {abbr}]])                  *hasmapto()*
                The result is a Number, which is 1 if there is a mapping that
                contains {what} in somewhere in the rhs (what it is mapped to)
                and this mapping exists in one of the modes indicated by
                {mode}.
                When {abbr} is there and it is non-zero use abbreviations
                instead of mappings.  Don't forget to specify Insert and/or
                Command-line mode.
                Both the global mappings and the mappings local to the current
                buffer are checked for a match.
                If no matching mapping is found 0 is returned.
                The following characters are recognized in {mode}:
                        n  Normal mode
                        v   Visual mode
                        o   Operator-pending mode
                        i   Insert mode
                        l   Language-Argument ("r", "f", "t", etc.)
                        c   Command-line mode
                When {mode} is omitted, "nvo" is used.

                This function is useful to check if a mapping already exists
                to a function in a Vim script.  Example:
                     :if !hasmapto('\ABCdoit')
                     :   map <Leader>d \ABCdoit
                     :endif
                This installs the mapping to "\ABCdoit" only if there isn't
                already a mapping to "\ABCdoit".


histadd({history}, {item})                              *histadd()*
                Add the String {item} to the history {history} which can be

                one of:                                 *hist-names*
                        "cmd"  or ":"    command line history
                        "search" or "/"   search pattern history
                        "expr"   or "="   typed expression history
                        "input"  or "@"   input line history
                If {item} does already exist in the history, it will be
                shifted to become the newest entry.
                The result is a Number: 1 if the operation was successful,
                otherwise 0 is returned.

                Example:
                     :call histadd("input", strftime("%Y %b %d"))
                     :let date=input("Enter date: ")
                This function is not available in the |sandbox|.


histdel({history} [, {item}])                           *histdel()*
                Clear {history}, i.e. delete all its entries.  See |hist-names|
                for the possible values of {history}.

                If the parameter {item} is given as String, this is seen
                as regular expression.  All entries matching that expression
                will be removed from the history (if there are any).
                Upper/lowercase must match, unless "\c" is used |/\c|.
                If {item} is a Number, it will be interpreted as index, see
                |:history-indexing|.  The respective entry will be removed
                if it exists.

                The result is a Number: 1 for a successful operation,
                otherwise 0 is returned.

                Examples:
                Clear expression register history:
                     :call histdel("expr")
 
                Remove all entries starting with "*" from the search history:
                     :call histdel("/", '^\*')
 
                The following three are equivalent:
                     :call histdel("search", histnr("search"))
                     :call histdel("search", -1)
                     :call histdel("search", '^'.histget("search", -1).'$')
 
                To delete the last search pattern and use the last-but-one for
                the "n" command and 'hlsearch':
                     :call histdel("search", -1)
                     :let @/ = histget("search", -1)


histget({history} [, {index}])                          *histget()*
                The result is a String, the entry with Number {index} from
                {history}.  See |hist-names| for the possible values of
                {history}, and |:history-indexing| for {index}.  If there is
                no such entry, an empty String is returned.  When {index} is
                omitted, the most recent item from the history is used.

                Examples:
                Redo the second last search from history.
                     :execute '/' . histget("search", -2)

                Define an Ex command ":H {num}" that supports re-execution of
                the {num}th entry from the output of |:history|.
                     :command -nargs=1 H execute histget("cmd", 0+<args>)
 

histnr({history})                                       *histnr()*
                The result is the Number of the current entry in {history}.
                See |hist-names| for the possible values of {history}.
                If an error occurred, -1 is returned.

                Example:
                     :let inp_index = histnr("expr")
 

hlexists({name})                                        *hlexists()*
                The result is a Number, which is non-zero if a highlight group
                called {name} exists.  This is when the group has been
                defined in some way.  Not necessarily when highlighting has
                been defined for it, it may also have been used for a syntax
                item.

                                                        *highlight_exists()*
                Obsolete name: highlight_exists().


                                                        *hlID()*
hlID({name})    The result is a Number, which is the ID of the highlight group
                with name {name}.  When the highlight group doesn't exist,
                zero is returned.
                This can be used to retrieve information about the highlight
                group.  For example, to get the background color of the
                "Comment" group:
     :echo synIDattr(synIDtrans(hlID("Comment")), "bg")

                                                        *highlightID()*
                Obsolete name: highlightID().


hostname()                                            *hostname()*
                The result is a String, which is the name of the machine on
                which Vim is currently running.  Machine names greater than
                256 characters long are truncated.


iconv({expr}, {from}, {to})                             *iconv()*
                The result is a String, which is the text {expr} converted
                from encoding {from} to encoding {to}.
                When the conversion fails an empty string is returned.
                The encoding names are whatever the iconv() library function
                can accept, see ":!man 3 iconv".
                Most conversions require Vim to be compiled with the |+iconv|
                feature.  Otherwise only UTF-8 to latin1 conversion and back
                can be done.
                This can be used to display messages with special characters,
                no matter what 'encoding' is set to.  Write the message in
                UTF-8 and use:
                     echo iconv(utf8_str, "utf-8", &enc)
                Note that Vim uses UTF-8 for all Unicode encodings, conversion
                from/to UCS-2 is automatically changed to use UTF-8.  You
                cannot use UCS-2 in a string anyway, because of the NUL bytes.
                {only available when compiled with the +multi_byte feature}


                                                        *indent()*
indent({lnum})  The result is a Number, which is indent of line {lnum} in the
                current buffer.  The indent is counted in spaces, the value
                of 'tabstop' is relevant.  {lnum} is used just like in
                |getline()|.
                When {lnum} is invalid -1 is returned.



index({list}, {expr} [, {start} [, {ic}]])                      *index()*
                Return the lowest index in |List| {list} where the item has a
                value equal to {expr}.
                If {start} is given then start looking at the item with index
                {start} (may be negative for an item relative to the end).
                When {ic} is given and it is non-zero, ignore case.  Otherwise
                case must match.
                -1 is returned when {expr} is not found in {list}.
                Example:
                     :let idx = index(words, "the")
                     :if index(numbers, 123) >= 0



input({prompt} [, {text} [, {completion}]])             *input()*
                The result is a String, which is whatever the user typed on
                the command-line.  The parameter is either a prompt string, or
                a blank string (for no prompt).  A '\n' can be used in the
                prompt to start a new line.
                The highlighting set with |:echohl| is used for the prompt.
                The input is entered just like a command-line, with the same
                editing commands and mappings.  There is a separate history
                for lines typed for input().
                Example:
                     :if input("Coffee or beer? ") == "beer"
                     :  echo "Cheers!"
                     :endif
 
                If the optional {text} is present and not empty, this is used
                for the default reply, as if the user typed this.  Example:
                     :let color = input("Color? ", "white")

                The optional {completion} argument specifies the type of
                completion supported for the input.  Without it completion is
                not performed.  The supported completion types are the same as
                that can be supplied to a user-defined command using the
                "-complete=" argument.  Refer to |:command-completion| for
                more information.  Example:
                     let fname = input("File: ", "", "file")
 
                NOTE: This function must not be used in a startup file, for
                the versions that only run in GUI mode (e.g., the Win32 GUI).
                Note: When input() is called from within a mapping it will
                consume remaining characters from that mapping, because a
                mapping is handled like the characters were typed.
                Use |inputsave()| before input() and |inputrestore()|
                after input() to avoid that.  Another solution is to avoid
                that further characters follow in the mapping, e.g., by using
                |:execute| or |:normal|.

                Example with a mapping:
                     :nmap \x :call GetFoo()<CR>:exe "/" . Foo<CR>
                     :function GetFoo()
                     :  call inputsave()
                     :  let g:Foo = input("enter search pattern: ")
                     :  call inputrestore()
                     :endfunction


inputdialog({prompt} [, {text} [, {cancelreturn}]])             *inputdialog()*
                Like input(), but when the GUI is running and text dialogs are
                supported, a dialog window pops up to input the text.
                Example:
                     :let n = inputdialog("value for shiftwidth", &sw)
                     :if n != ""
                     :  let &sw = n
                     :endif
                When the dialog is cancelled {cancelreturn} is returned.  When
                omitted an empty string is returned.
                Hitting <Enter> works like pressing the OK button.  Hitting
                <Esc> works like pressing the Cancel button.
                NOTE: Command-line completion is not supported.


inputlist({textlist})                                   *inputlist()*
                {textlist} must be a |List| of strings.  This |List| is
                displayed, one string per line.  The user will be prompted to
                enter a number, which is returned.
                The user can also select an item by clicking on it with the
                mouse.  For the first string 0 is returned.  When clicking
                above the first item a negative number is returned.  When
                clicking on the prompt one more than the length of {textlist}
                is returned.
                Make sure {textlist} has less then 'lines' entries, otherwise
                it won't work.  It's a good idea to put the entry number at
                the start of the string.  Example:
                     let color = inputlist(['Select color:', '1. red',
                             \ '2. green', '3. blue'])


inputrestore()                                            *inputrestore()*
                Restore typeahead that was saved with a previous inputsave().
                Should be called the same number of times inputsave() is
                called.  Calling it more often is harmless though.
                Returns 1 when there is nothing to restore, 0 otherwise.


inputsave()                                          *inputsave()*
                Preserve typeahead (also from mappings) and clear it, so that
                a following prompt gets input from the user.  Should be
                followed by a matching inputrestore() after the prompt.  Can
                be used several times, in which case there must be just as
                many inputrestore() calls.
                Returns 1 when out of memory, 0 otherwise.


inputsecret({prompt} [, {text}])                        *inputsecret()*
                This function acts much like the |input()| function with but
                two exceptions:
                a) the user's response will be displayed as a sequence of
                asterisks ("*") thereby keeping the entry secret, and
                b) the user's response will not be recorded on the input
                |history| stack.
                The result is a String, which is whatever the user actually
                typed on the command-line in response to the issued prompt.
                NOTE: Command-line completion is not supported.


insert({list}, {item} [, {idx}])                        *insert()*
                Insert {item} at the start of |List| {list}.
                If {idx} is specified insert {item} before the item with index
                {idx}.  If {idx} is zero it goes before the first item, just
                like omitting {idx}.  A negative {idx} is also possible, see
                |list-index|.  -1 inserts just before the last item.
                Returns the resulting |List|.  Examples:
                     :let mylist = insert([2, 3, 5], 1)
                     :call insert(mylist, 4, -1)
                     :call insert(mylist, 6, len(mylist))
                The last example can be done simpler with |add()|.
                Note that when {item} is a |List| it is inserted as a single
                item.  Use |extend()| to concatenate |Lists|.


isdirectory({directory})                                *isdirectory()*
                The result is a Number, which is non-zero when a directory
                with the name {directory} exists.  If {directory} doesn't
                exist, or isn't a directory, the result is FALSE.  {directory}
                is any expression, which is used as a String.


islocked({expr})                                        *islocked()* *E786*
                The result is a Number, which is non-zero when {expr} is the
                name of a locked variable.
                {expr} must be the name of a variable, |List| item or
                |Dictionary| entry, not the variable itself!  Example:
                     :let alist = [0, ['a', 'b'], 2, 3]
                     :lockvar 1 alist
                     :echo islocked('alist')         " 1
                     :echo islocked('alist[1]')      " 0

                When {expr} is a variable that does not exist you get an error
                message.  Use |exists()| to check for existence.


items({dict})                                           *items()*
                Return a |List| with all the key-value pairs of {dict}.  Each
                |List| item is a list with two items: the key of a {dict}
                entry and the value of this entry.  The |List| is in arbitrary
                order.



join({list} [, {sep}])                                  *join()*
                Join the items in {list} together into one String.
                When {sep} is specified it is put in between the items.  If
                {sep} is omitted a single space is used.
                Note that {sep} is not added at the end.  You might want to
                add it there too:
                     let lines = join(mylist, "\n") . "\n"
                String items are used as-is.  |Lists| and |Dictionaries| are
                converted into a string like with |string()|.
                The opposite function is |split()|.


keys({dict})                                            *keys()*
                Return a |List| with all the keys of {dict}.  The |List| is in
                arbitrary order.


                                                        *len()* *E701*
len({expr})     The result is a Number, which is the length of the argument.
                When {expr} is a String or a Number the length in bytes is
                used, as with |strlen()|.
                When {expr} is a |List| the number of items in the |List| is
                returned.
                When {expr} is a |Dictionary| the number of entries in the
                |Dictionary| is returned.
                Otherwise an error is given.


                                                *libcall()* *E364* *E368*
libcall({libname}, {funcname}, {argument})
                Call function {funcname} in the run-time library {libname}
                with single argument {argument}.
                This is useful to call functions in a library that you
                especially made to be used with Vim.  Since only one argument
                is possible, calling standard library functions is rather
                limited.
                The result is the String returned by the function.  If the
                function returns NULL, this will appear as an empty string ""
                to Vim.
                If the function returns a number, use libcallnr()!
                If {argument} is a number, it is passed to the function as an
                int; if {argument} is a string, it is passed as a
                null-terminated string.
                This function will fail in |restricted-mode|.

                libcall() allows you to write your own 'plug-in' extensions to
                Vim without having to recompile the program.  It is NOT a
                means to call system functions!  If you try to do so Vim will
                very probably crash.

                For Win32, the functions you write must be placed in a DLL
                and use the normal C calling convention (NOT Pascal which is
                used in Windows System DLLs).  The function must take exactly
                one parameter, either a character pointer or a long integer,
                and must return a character pointer or NULL.  The character
                pointer returned must point to memory that will remain valid
                after the function has returned (e.g. in static data in the
                DLL).  If it points to allocated memory, that memory will
                leak away.  Using a static buffer in the function should work,
                it's then freed when the DLL is unloaded.

                WARNING: If the function returns a non-valid pointer, Vim may
                crash!  This also happens if the function returns a number,
                because Vim thinks it's a pointer.
                For Win32 systems, {libname} should be the filename of the DLL
                without the ".DLL" suffix.  A full path is only required if
                the DLL is not in the usual places.
                For Unix: When compiling your own plugins, remember that the
                object code must be compiled as position-independent ('PIC').
                {only in Win32 on some Unix versions, when the |+libcall|
                feature is present}
                Examples:
                     :echo libcall("libc.so", "getenv", "HOME")
                     :echo libcallnr("/usr/lib/libc.so", "getpid", "")
 

                                                        *libcallnr()*
libcallnr({libname}, {funcname}, {argument})
                Just like libcall(), but used for a function that returns an
                int instead of a string.
                {only in Win32 on some Unix versions, when the |+libcall|
                feature is present}
                Example (not very useful...):
                     :call libcallnr("libc.so", "printf", "Hello World!\n")
                     :call libcallnr("libc.so", "sleep", 10)
 

                                                        *line()*
line({expr})    The result is a Number, which is the line number of the file
                position given with {expr}.  The accepted positions are:
                    .       the cursor position
                    $       the last line in the current buffer
                    'x      position of mark x (if the mark is not set, 0 is
                            returned)
                    w0      first line visible in current window
                    w$      last line visible in current window
                Note that a mark in another file can be used.
                To get the column number use |col()|.  To get both use
                |getpos()|.
                Examples:
                     line(".")               line number of the cursor
                     line("'t")              line number of mark t
                     line("'" . marker)      line number of mark marker

                                                        *last-position-jump*
                This autocommand jumps to the last known position in a file
                just after opening it, if the '"' mark is set:
     :au BufReadPost * if line("'\"") > 0 && line("'\"") <= line("$") | exe "normal g'\"" | endif


line2byte({lnum})                                       *line2byte()*
                Return the byte count from the start of the buffer for line
                {lnum}.  This includes the end-of-line character, depending on
                the 'fileformat' option for the current buffer.  The first
                line returns 1.
                This can also be used to get the byte count for the line just
                below the last line:
                     line2byte(line("$") + 1)
                This is the file size plus one.
                When {lnum} is invalid, or the |+byte_offset| feature has been
                disabled at compile time, -1 is returned.
                Also see |byte2line()|, |go| and |:goto|.


lispindent({lnum})                                      *lispindent()*
                Get the amount of indent for line {lnum} according the lisp
                indenting rules, as with 'lisp'.
                The indent is counted in spaces, the value of 'tabstop' is
                relevant.  {lnum} is used just like in |getline()|.
                When {lnum} is invalid or Vim was not compiled the
                |+lispindent| feature, -1 is returned.


localtime()                                          *localtime()*
                Return the current time, measured as seconds since 1st Jan
                1970.  See also |strftime()| and |getftime()|.



map({expr}, {string})                                   *map()*
                {expr} must be a |List| or a |Dictionary|.
                Replace each item in {expr} with the result of evaluating
                {string}.
                Inside {string} |v:val| has the value of the current item.
                For a |Dictionary| |v:key| has the key of the current item.
                Example:
                     :call map(mylist, '"> " . v:val . " <"')
                This puts "> " before and " <" after each item in "mylist".

                Note that {string} is the result of an expression and is then
                used as an expression again.  Often it is good to use a
                |literal-string| to avoid having to double backslashes.  You
                still have to double '' quotes

                The operation is done in-place.  If you want a |List| or
                |Dictionary| to remain unmodified make a copy first:
                     :let tlist = map(copy(mylist), ' & . "\t"')

                Returns {expr}, the |List| or |Dictionary| that was filtered.
                When an error is encountered while evaluating {string} no
                further items in {expr} are processed.



maparg({name}[, {mode} [, {abbr}]])                     *maparg()*
                Return the rhs of mapping {name} in mode {mode}.  When there
                is no mapping for {name}, an empty String is returned.
                {mode} can be one of these strings:
                        "n"      Normal
                        "v"       Visual
                        "o"       Operator-pending
                        "i"       Insert
                        "c"       Cmd-line
                        "l"   langmap |language-mapping|
                        ""    Normal, Visual and Operator-pending
                When {mode} is omitted, the modes for "" are used.
                When {abbr} is there and it is non-zero use abbreviations
                instead of mappings.
                The {name} can have special key names, like in the ":map"
                command.  The returned String has special characters
                translated like in the output of the ":map" command listing.
                The mappings local to the current buffer are checked first,
                then the global mappings.
                This function can be used to map a key even when it's already
                mapped, and have it do the original mapping too.  Sketch:
                     exe 'nnoremap <Tab> ==' . maparg('<Tab>', 'n')



mapcheck({name}[, {mode} [, {abbr}]])                   *mapcheck()*
                Check if there is a mapping that matches with {name} in mode
                {mode}.  See |maparg()| for {mode} and special names in
                {name}.
                When {abbr} is there and it is non-zero use abbreviations
                instead of mappings.
                A match happens with a mapping that starts with {name} and
                with a mapping which is equal to the start of {name}.

                        matches mapping "a"     "ab"    "abc" 
                   mapcheck("a")      yes     yes      yes
                   mapcheck("abc")    yes     yes      yes
                   mapcheck("ax")     yes     no       no
                   mapcheck("b")      no      no       no

                The difference with maparg() is that mapcheck() finds a
                mapping that matches with {name}, while maparg() only finds a
                mapping for {name} exactly.
                When there is no mapping that starts with {name}, an empty
                String is returned.  If there is one, the rhs of that mapping
                is returned.  If there are several mappings that start with
                {name}, the rhs of one of them is returned.
                The mappings local to the current buffer are checked first,
                then the global mappings.
                This function can be used to check if a mapping can be added
                without being ambiguous.  Example:
     :if mapcheck("_vv") == ""
     :   map _vv :set guifont=7x13<CR>
     :endif
                This avoids adding the "_vv" mapping when there already is a
                mapping for "_v" or for "_vvv".


match({expr}, {pat}[, {start}[, {count}]])                      *match()*
                When {expr} is a |List| then this returns the index of the
                first item where {pat} matches.  Each item is used as a
                String, |Lists| and |Dictionaries| are used as echoed.
                Otherwise, {expr} is used as a String.  The result is a
                Number, which gives the index (byte offset) in {expr} where
                {pat} matches.
                A match at the first character or |List| item returns zero.
                If there is no match -1 is returned.
                Example:
                     :echo match("testing", "ing")   " results in 4
                     :echo match([1, 'x'], '\a')     " results in 1
                See |string-match| for how {pat} is used.

                                                                *strpbrk()*
                Vim doesn't have a strpbrk() function.  But you can do:
                     :let sepidx = match(line, '[.,;: \t]')

                                                                *strcasestr()*
                Vim doesn't have a strcasestr() function.  But you can add
                "\c" to the pattern to ignore case:
                     :let idx = match(haystack, '\cneedle')
 
                If {start} is given, the search starts from byte index
                {start} in a String or item {start} in a |List|.
                The result, however, is still the index counted from the
                first character/item.  Example:
                     :echo match("testing", "ing", 2)
                result is again "4".
                     :echo match("testing", "ing", 4)
                result is again "4".
                     :echo match("testing", "t", 2)
                result is "3".
                For a String, if {start} > 0 then it is like the string starts
                {start} bytes later, thus "^" will match at {start}.  Except
                when {count} is given, then it's like matches before the
                {start} byte are ignored (this is a bit complicated to keep it
                backwards compatible).
                For a String, if {start} < 0, it will be set to 0.  For a list
                the index is counted from the end.
                If {start} is out of range ({start} > strlen({expr}) for a
                String or {start} > len({expr}) for a |List|) -1 is returned.

                When {count} is given use the {count}'th match.  When a match
                is found in a String the search for the next one starts one
                character further.  Thus this example results in 1:
                     echo match("testing", "..", 0, 2)
                In a |List| the search continues in the next item.
                Note that when {count} is added the way {start} works changes,
                see above.

                See |pattern| for the patterns that are accepted.
                The 'ignorecase' option is used to set the ignore-caseness of
                the pattern.  'smartcase' is NOT used.  The matching is always
                done like 'magic' is set and 'cpoptions' is empty.



matcharg({nr})                                                  *matcharg()*
                Selects the {nr} match item, as set with a |:match|,
                |:2match| or |:3match| command.
                Return a |List| with two elements:
                        The name of the highlight group used
                        The pattern used.
                When {nr} is not 1, 2 or 3 returns an empty |List|.
                When there is no match item set returns ['', ''].
                This is usef to save and restore a |:match|.



matchend({expr}, {pat}[, {start}[, {count}]])                   *matchend()*
                Same as match(), but return the index of first character after
                the match.  Example:
                     :echo matchend("testing", "ing")
                results in "7".

                                                        *strspn()* *strcspn()*
                Vim doesn't have a strspn() or strcspn() function, but you can
                do it with matchend():
                     :let span = matchend(line, '[a-zA-Z]')
                     :let span = matchend(line, '[^a-zA-Z]')
                Except that -1 is returned when there are no matches.

                The {start}, if given, has the same meaning as for match().
                     :echo matchend("testing", "ing", 2)
                results in "7".
                     :echo matchend("testing", "ing", 5)
                result is "-1".
                When {expr} is a |List| the result is equal to match().


matchlist({expr}, {pat}[, {start}[, {count}]])                  *matchlist()*
                Same as match(), but return a |List|.  The first item in the
                list is the matched string, same as what matchstr() would
                return.  Following items are submatches, like "\1", "\2", etc.
                in |:substitute|.  When an optional submatch didn't match an
                empty string is used.  Example:
                     echo matchlist('acd', '\(a\)\?\(b\)\?\(c\)\?\(.*\)')
                Results in: ['acd', 'a', '', 'c', 'd', '', '', '', '', '']
                When there is no match an empty list is returned.


matchstr({expr}, {pat}[, {start}[, {count}]])                   *matchstr()*
                Same as match(), but return the matched string.  Example:
                     :echo matchstr("testing", "ing")
                results in "ing".
                When there is no match "" is returned.
                The {start}, if given, has the same meaning as for match().
                     :echo matchstr("testing", "ing", 2)
                results in "ing".
                     :echo matchstr("testing", "ing", 5)
                result is "".
                When {expr} is a |List| then the matching item is returned.
                The type isn't changed, it's not necessarily a String.


                                                        *max()*
max({list})     Return the maximum value of all items in {list}.
                If {list} is not a list or one of the items in {list} cannot
                be used as a Number this results in an error.
                An empty |List| results in zero.


                                                        *min()*
min({list})     Return the minumum value of all items in {list}.
                If {list} is not a list or one of the items in {list} cannot
                be used as a Number this results in an error.
                An empty |List| results in zero.


                                                        *mkdir()* *E739*
mkdir({name} [, {path} [, {prot}]])
                Create directory {name}.
                If {path} is "p" then intermediate directories are created as
                necessary.  Otherwise it must be "".
                If {prot} is given it is used to set the protection bits of
                the new directory.  The default is 0755 (rwxr-xr-x: r/w for
                the user readable for others).  Use 0700 to make it unreadable
                for others.
                This function is not available in the |sandbox|.
                Not available on all systems.  To check use:
                     :if exists("*mkdir")
 

                                                        *mode()*
mode()            Return a string that indicates the current mode:
                        n  Normal
                        v   Visual by character
                        V   Visual by line
                        CTRL-V Visual blockwise
                        s   Select by character
                        S   Select by line
                        CTRL-S  Select blockwise
                        i   Insert
                        R   Replace
                        c   Command-line
                        r   Hit-enter prompt
                This is useful in the 'statusline' option.  In most other
                places it always returns "c" or "n".


nextnonblank({lnum})                                    *nextnonblank()*
                Return the line number of the first line at or below {lnum}
                that is not blank.  Example:
                     if getline(nextnonblank(1)) =~ "Java"
                When {lnum} is invalid or there is no non-blank line at or
                below it, zero is returned.
                See also |prevnonblank()|.


nr2char({expr})                                         *nr2char()*
                Return a string with a single character, which has the number
                value {expr}.  Examples:
                     nr2char(64)             returns "@"
                     nr2char(32)             returns " "
                The current 'encoding' is used.  Example for "utf-8":
                     nr2char(300)            returns I with bow character
                Note that a NUL character in the file is specified with
                nr2char(10), because NULs are represented with newline
                characters.  nr2char(0) is a real NUL and terminates the
                string, thus results in an empty string.


                                                        *getpos()*
getpos({expr})  Get the position for {expr}.  For possible values of {expr}
                see |line()|.
                The result is a |List| with four numbers:
                    [bufnum, lnum, col, off]
                "bufnum" is zero, unless a mark like '0 or 'A is used, then it
                is the buffer number of the mark.
                "lnum" and "col" are the position in the buffer.  The first
                column is 1.
                The "off" number is zero, unless 'virtualedit' is used.  Then
                it is the offset in screen columns from the start of the
                character.  E.g., a position within a Tab or after the last
                character.
                This can be used to save and restore the cursor position:
                     let save_cursor = getpos(".")
                     MoveTheCursorAround
                     call setpos('.', save_cursor)
                Also see |setpos()|.


pathshorten({expr})                                     *pathshorten()*
                Shorten directory names in the path {expr} and return the
                result.  The tail, the file name, is kept as-is.  The other
                components in the path are reduced to single letters.  Leading
                '~' and '.' characters are kept.  Example:
                     :echo pathshorten('~/.vim/autoload/myfile.vim')
                        ~/.v/a/myfile.vim 
                It doesn't matter if the path exists or not.


prevnonblank({lnum})                                    *prevnonblank()*
                Return the line number of the first line at or above {lnum}
                that is not blank.  Example:
                     let ind = indent(prevnonblank(v:lnum - 1))
                When {lnum} is invalid or there is no non-blank line at or
                above it, zero is returned.
                Also see |nextnonblank()|.



printf({fmt}, {expr1} ...)                              *printf()*
                Return a String with {fmt}, where "%" items are replaced by
                the formatted form of their respective arguments.  Example:
                     printf("%4d: E%d %.30s", lnum, errno, msg)
                May result in:
                        "  99: E42 asdfasdfasdfasdfasdfasdfasdfas" 

                Often used items are:
                  %s        string
                  %6s       string right-aligned in 6 bytes
                  %.9s  string truncated to 9 bytes
                  %c    single byte
                  %d    decimal number
                  %5d   decimal number padded with spaces to 5 characters
                  %x    hex number
                  %04x  hex number padded with zeros to at least 4 characters
                  %X    hex number using upper case letters
                  %o    octal number
                  %%    the % character itself

                Conversion specifications start with '%' and end with the
                conversion type.  All other characters are copied unchanged to
                the result.

                The "%" starts a conversion specification.  The following
                arguments appear in sequence:

                        %  [flags]  [field-width]  [.precision]  type

                flags
                        Zero or more of the following flags:

                    #         The value should be converted to an "alternate
                              form".  For c, d, and s conversions, this option
                              has no effect.  For o conversions, the precision
                              of the number is increased to force the first
                              character of the output string to a zero (except
                              if a zero value is printed with an explicit
                              precision of zero).
                              For x and X conversions, a non-zero result has
                              the string "0x" (or "0X" for X conversions)
                              prepended to it.

                    0 (zero)  Zero padding.  For all conversions the converted
                              value is padded on the left with zeros rather
                              than blanks.  If a precision is given with a
                              numeric conversion (d, o, x, and X), the 0 flag
                              is ignored.

                    -         A negative field width flag; the converted value
                              is to be left adjusted on the field boundary.
                              The converted value is padded on the right with
                              blanks, rather than on the left with blanks or
                              zeros.  A - overrides a 0 if both are given.

                    '' '' (space)  A blank should be left before a positive
                              number produced by a signed conversion (d).

                    +         A sign must always be placed before a number
                              produced by a signed conversion.  A + overrides
                              a space if both are used.

                field-width
                        An optional decimal digit string specifying a minimum
                        field width.  If the converted value has fewer bytes
                        than the field width, it will be padded with spaces on
                        the left (or right, if the left-adjustment flag has
                        been given) to fill out the field width.

                .precision
                        An optional precision, in the form of a period '.'
                        followed by an optional digit string.  If the digit
                        string is omitted, the precision is taken as zero.
                        This gives the minimum number of digits to appear for
                        d, o, x, and X conversions, or the maximum number of
                        bytes to be printed from a string for s conversions.

                type
                        A character that specifies the type of conversion to
                        be applied, see below.

                A field width or precision, or both, may be indicated by an
                asterisk '*' instead of a digit string.  In this case, a
                Number argument supplies the field width or precision.  A
                negative field width is treated as a left adjustment flag
                followed by a positive field width; a negative precision is
                treated as though it were missing.  Example:
                     :echo printf("%d: %.*s", nr, width, line)
                This limits the length of the text used from "line" to
                "width" bytes.

                The conversion specifiers and their meanings are:

                doxX    The Number argument is converted to signed decimal
                        (d), unsigned octal (o), or unsigned hexadecimal (x
                        and X) notation.  The letters "abcdef" are used for
                        x conversions; the letters "ABCDEF" are used for X
                        conversions.
                        The precision, if any, gives the minimum number of
                        digits that must appear; if the converted value
                        requires fewer digits, it is padded on the left with
                        zeros.
                        In no case does a non-existent or small field width
                        cause truncation of a numeric field; if the result of
                        a conversion is wider than the field width, the field
                        is expanded to contain the conversion result.

                c   The Number argument is converted to a byte, and the
                        resulting character is written.

                s   The text of the String argument is used.  If a
                        precision is specified, no more bytes than the number
                        specified are used.

                %       A '%' is written.  No argument is converted.  The
                        complete conversion specification is "%%".

                Each argument can be Number or String and is converted
                automatically to fit the conversion specifier.  Any other
                argument type results in an error message.


                                                        *E766* *E767*
                The number of {exprN} arguments must exactly match the number
                of "%" items.  If there are not sufficient or too many
                arguments an error is given.  Up to 18 arguments can be used.



pumvisible()                                                *pumvisible()*
                Returns non-zero when the popup menu is visible, zero
                otherwise.  See |ins-completion-menu|.
                This can be used to avoid some things that would remove the
                popup menu.


                                                        *E726* *E727*

range({expr} [, {max} [, {stride}]])                            *range()*
                Returns a |List| with Numbers:
                - If only {expr} is specified: [0, 1, ..., {expr} - 1]
                - If {max} is specified: [{expr}, {expr} + 1, ..., {max}]
                - If {stride} is specified: [{expr}, {expr} + {stride}, ...,
                  {max}] (increasing {expr} with {stride} each time, not
                  producing a value past {max}).
                When the maximum is one before the start the result is an
                empty list.  When the maximum is more than one before the
                start this is an error.
                Examples:
                     range(4)                " [0, 1, 2, 3]
                     range(2, 4)             " [2, 3, 4]
                     range(2, 9, 3)          " [2, 5, 8]
                     range(2, -2, -1)        " [2, 1, 0, -1, -2]
                     range(0)                " []
                     range(2, 0)             " error!
 

                                                        *readfile()*
readfile({fname} [, {binary} [, {max}]])
                Read file {fname} and return a |List|, each line of the file
                as an item.  Lines broken at NL characters.  Macintosh files
                separated with CR will result in a single long line (unless a
                NL appears somewhere).
                When {binary} is equal to "b" binary mode is used:
                - When the last line ends in a NL an extra empty list item is
                  added.
                - No CR characters are removed.
                Otherwise:
                - CR characters that appear before a NL are removed.
                - Whether the last line ends in a NL or not does not matter.
                All NUL characters are replaced with a NL character.
                When {max} is given this specifies the maximum number of lines
                to be read.  Useful if you only want to check the first ten
                lines of a file:
                     :for line in readfile(fname, '', 10)
                     :  if line =~ 'Date' | echo line | endif
                     :endfor
                When {max} is negative -{max} lines from the end of the file
                are returned, or as many as there are.
                When {max} is zero the result is an empty list.
                Note that without {max} the whole file is read into memory.
                Also note that there is no recognition of encoding.  Read a
                file into a buffer if you need to.
                When the file can't be opened an error message is given and
                the result is an empty list.
                Also see |writefile()|.


reltime([{start} [, {end}]])                            *reltime()*
                Return an item that represents a time value.  The format of
                the item depends on the system.  It can be passed to
                |reltimestr()| to convert it to a string.
                Without an argument it returns the current time.
                With one argument is returns the time passed since the time
                specified in the argument.
                With two arguments it returns the time passed between {start}
                and {end}.
                The {start} and {end} arguments must be values returned by
                reltime().
                {only available when compiled with the +reltime feature}


reltimestr({time})                              *reltimestr()*
                Return a String that represents the time value of {time}.
                This is the number of seconds, a dot and the number of
                microseconds.  Example:
                     let start = reltime()
                     call MyFunction()
                     echo reltimestr(reltime(start))
                Note that overhead for the commands will be added to the time.
                The accuracy depends on the system.
                Also see |profiling|.
                {only available when compiled with the +reltime feature}


                                                        *remote_expr()* *E449*
remote_expr({server}, {string} [, {idvar}])
                Send the {string} to {server}.  The string is sent as an
                expression and the result is returned after evaluation.
                The result must be a String or a |List|.  A |List| is turned
                into a String by joining the items with a line break in
                between (not at the end), like with join(expr, "\n").
                If {idvar} is present, it is taken as the name of a
                variable and a {serverid} for later use with
                remote_read() is stored there.
                See also |clientserver| |RemoteReply|.
                This function is not available in the |sandbox|.
                {only available when compiled with the |+clientserver| feature}
                Note: Any errors will cause a local error message to be issued
                and the result will be the empty string.
                Examples:
                     :echo remote_expr("gvim", "2+2")
                     :echo remote_expr("gvim1", "b:current_syntax")
 


remote_foreground({server})                             *remote_foreground()*
                Move the Vim server with the name {server} to the foreground.
                This works like:
                     remote_expr({server}, "foreground()")
                Except that on Win32 systems the client does the work, to work
                around the problem that the OS doesn't always allow the server
                to bring itself to the foreground.
                Note: This does not restore the window if it was minimized,
                like foreground() does.
                This function is not available in the |sandbox|.
                {only in the Win32, Athena, Motif and GTK GUI versions and the
                Win32 console version}



remote_peek({serverid} [, {retvar}])            *remote_peek()*
                Returns a positive number if there are available strings
                from {serverid}.  Copies any reply string into the variable
                {retvar} if specified.  {retvar} must be a string with the
                name of a variable.
                Returns zero if none are available.
                Returns -1 if something is wrong.
                See also |clientserver|.
                This function is not available in the |sandbox|.
                {only available when compiled with the |+clientserver| feature}
                Examples:
                     :let repl = ""
                     :echo "PEEK: ".remote_peek(id, "repl").": ".repl


remote_read({serverid})                         *remote_read()*
                Return the oldest available reply from {serverid} and consume
                it.  It blocks until a reply is available.
                See also |clientserver|.
                This function is not available in the |sandbox|.
                {only available when compiled with the |+clientserver| feature}
                Example:
                     :echo remote_read(id)
 

                                                        *remote_send()* *E241*
remote_send({server}, {string} [, {idvar}])
                Send the {string} to {server}.  The string is sent as input
                keys and the function returns immediately.  At the Vim server
                the keys are not mapped |:map|.
                If {idvar} is present, it is taken as the name of a variable
                and a {serverid} for later use with remote_read() is stored
                there.
                See also |clientserver| |RemoteReply|.
                This function is not available in the |sandbox|.
                {only available when compiled with the |+clientserver| feature}
                Note: Any errors will be reported in the server and may mess
                up the display.
                Examples:
             :echo remote_send("gvim", ":DropAndReply ".file, "serverid").
              \ remote_read(serverid)

             :autocmd NONE RemoteReply *
              \ echo remote_read(expand("<amatch>"))
             :echo remote_send("gvim", ":sleep 10 | echo ".
              \ 'server2client(expand("<client>"), "HELLO")<CR>')
 

remove({list}, {idx} [, {end}])                         *remove()*
                Without {end}: Remove the item at {idx} from |List| {list} and
                return it.
                With {end}: Remove items from {idx} to {end} (inclusive) and
                return a list with these items.  When {idx} points to the same
                item as {end} a list with one item is returned.  When {end}
                points to an item before {idx} this is an error.
                See |list-index| for possible values of {idx} and {end}.
                Example:
                     :echo "last item: " . remove(mylist, -1)
                     :call remove(mylist, 0, 9)
remove({dict}, {key})
                Remove the entry from {dict} with key {key}.  Example:
                     :echo "removed " . remove(dict, "one")
                If there is no {key} in {dict} this is an error.

                Use |delete()| to remove a file.


rename({from}, {to})                                    *rename()*
                Rename the file by the name {from} to the name {to}.  This
                should also work to move files across file systems.  The
                result is a Number, which is 0 if the file was renamed
                successfully, and non-zero when the renaming failed.
                This function is not available in the |sandbox|.


repeat({expr}, {count})                                 *repeat()*
                Repeat {expr} {count} times and return the concatenated
                result.  Example:
                     :let separator = repeat('-', 80)
                When {count} is zero or negative the result is empty.
                When {expr} is a |List| the result is {expr} concatenated
                {count} times.  Example:
                     :let longlist = repeat(['a', 'b'], 3)
                Results in ['a', 'b', 'a', 'b', 'a', 'b'].



resolve({filename})                                     *resolve()* *E655*
                On MS-Windows, when {filename} is a shortcut (a .lnk file),
                returns the path the shortcut points to in a simplified form.
                On Unix, repeat resolving symbolic links in all path
                components of {filename} and return the simplified result.
                To cope with link cycles, resolving of symbolic links is
                stopped after 100 iterations.
                On other systems, return the simplified {filename}.
                The simplification step is done as by |simplify()|.
                resolve() keeps a leading path component specifying the
                current directory (provided the result is still a relative
                path name) and also keeps a trailing path separator.


                                                        *reverse()*
reverse({list}) Reverse the order of items in {list} in-place.  Returns
                {list}.
                If you want a list to remain unmodified make a copy first:
                     :let revlist = reverse(copy(mylist))


search({pattern} [, {flags} [, {stopline}]])                    *search()*
                Search for regexp pattern {pattern}.  The search starts at the
                cursor position (you can use |cursor()| to set it).

                {flags} is a String, which can contain these character flags:
                'b' search backward instead of forward
                'c'     accept a match at the cursor position
                'e' move to the End of the match
                'n'        do Not move the cursor
                'p' return number of matching sub-pattern (see below)
                's' set the '' mark at the previous location of the cursor
                'w' wrap around the end of the file
                'W' don't wrap around the end of the file
                If neither 'w' or 'W' is given, the 'wrapscan' option applies.

                If the 's' flag is supplied, the '' mark is set, only if the
                cursor is moved. The 's' flag cannot be combined with the 'n'
                flag.

                When the {stopline} argument is given then the search stops
                after searching this line.  This is useful to restrict the
                search to a range of lines.  Examples:
                     let match = search('(', 'b', line("w0"))
                     let end = search('END', '', line("w$"))
                When {stopline} is used and it is not zero this also implies
                that the search does not wrap around the end of the file.

                If there is no match a 0 is returned and the cursor doesn't
                move.  No error message is given.
                When a match has been found its line number is returned.

                                                        *search()-sub-match*
                With the 'p' flag the returned value is one more than the
                first sub-match in \(\).  One if none of them matched but the
                whole pattern did match.
                To get the column number too use |searchpos()|.

                The cursor will be positioned at the match, unless the 'n'
                flag is used.

                Example (goes over all files in the argument list):
                 :let n = 1
                 :while n <= argc()           " loop over all files in arglist
                 :  exe "argument " . n
                 :  " start at the last char in the file and wrap for the
                 :  " first search to find match at start of file
                 :  normal G$
                 :  let flags = "w"
                 :  while search("foo", flags) > 0
                 :    s/foo/bar/g
                 :    let flags = "W"
                 :  endwhile
                 :  update               " write the file if modified
                 :  let n = n + 1
                 :endwhile
 
                Example for using some flags:
                 :echo search('\<if\|\(else\)\|\(endif\)', 'ncpe')
                This will search for the keywords "if", "else", and "endif"
                under or after the cursor.  Because of the 'p' flag, it
                returns 1, 2, or 3 depending on which keyword is found, or 0
                if the search fails.  With the cursor on the first word of the
                line:
                    if (foo == 0) | let foo = foo + 1 | endif 
                the function returns 1.  Without the 'c' flag, the function
                finds the "endif" and returns 3.  The same thing happens
                without the 'e' flag if the cursor is on the "f" of "if".
                The 'n' flag tells the function not to move the cursor.



searchdecl({name} [, {global} [, {thisblock}]])                 *searchdecl()*
                Search for the declaration of {name}.

                With a non-zero {global} argument it works like |gD|, find
                first match in the file.  Otherwise it works like |gd|, find
                first match in the function.

                With a non-zero {thisblock} argument matches in a {} block
                that ends before the cursor position are ignored.  Avoids
                finding variable declarations only valid in another scope.

                Moves the cursor to the found match.
                Returns zero for success, non-zero for failure.
                Example:
                     if searchdecl('myvar') == 0
                        echo getline('.')
                     endif
 

                                                        *searchpair()*
searchpair({start}, {middle}, {end} [, {flags} [, {skip} [, {stopline}]]])
                Search for the match of a nested start-end pair.  This can be
                used to find the "endif" that matches an "if", while other
                if/endif pairs in between are ignored.
                The search starts at the cursor.  The default is to search
                forward, include 'b' in {flags} to search backward.
                If a match is found, the cursor is positioned at it and the
                line number is returned.  If no match is found 0 or -1 is
                returned and the cursor doesn't move.  No error message is
                given.

                {start}, {middle} and {end} are patterns, see |pattern|.  They
                must not contain \( \) pairs.  Use of \%( \) is allowed.  When
                {middle} is not empty, it is found when searching from either
                direction, but only when not in a nested start-end pair.  A
                typical use is:
                     searchpair('\<if\>', '\<else\>', '\<endif\>')
                By leaving {middle} empty the "else" is skipped.

                {flags} 'b', 'c', 'n', 's', 'w' and 'W' are used like with
                |search()|.  Additionally:
                'r' Repeat until no more matches found; will find the
                        outer pair
                'm' return number of Matches instead of line number with
                        the match; will be > 1 when 'r' is used.

                When a match for {start}, {middle} or {end} is found, the
                {skip} expression is evaluated with the cursor positioned on
                the start of the match.  It should return non-zero if this
                match is to be skipped.  E.g., because it is inside a comment
                or a string.
                When {skip} is omitted or empty, every match is accepted.
                When evaluating {skip} causes an error the search is aborted
                and -1 returned.

                For {stopline} see |search()|.

                The value of 'ignorecase' is used.  'magic' is ignored, the
                patterns are used like it's on.

                The search starts exactly at the cursor.  A match with
                {start}, {middle} or {end} at the next character, in the
                direction of searching, is the first one found.  Example:
                     if 1
                       if 2
                       endif 2
                     endif 1
                When starting at the "if 2", with the cursor on the "i", and
                searching forwards, the "endif 2" is found.  When starting on
                the character just before the "if 2", the "endif 1" will be
                found.  That's because the "if 2" will be found first, and
                then this is considered to be a nested if/endif from "if 2" to
                "endif 2".
                When searching backwards and {end} is more than one character,
                it may be useful to put "\zs" at the end of the pattern, so
                that when the cursor is inside a match with the end it finds
                the matching start.

                Example, to find the "endif" command in a Vim script:

     :echo searchpair('\<if\>', '\<el\%[seif]\>', '\<en\%[dif]\>', 'W',
                     \ 'getline(".") =~ "^\\s*\""')

                The cursor must be at or after the "if" for which a match is
                to be found.  Note that single-quote strings are used to avoid
                having to double the backslashes.  The skip expression only
                catches comments at the start of a line, not after a command.
                Also, a word "en" or "if" halfway a line is considered a
                match.
                Another example, to search for the matching "{" of a "}":

     :echo searchpair('{', '', '}', 'bW')

                This works when the cursor is at or before the "}" for which a
                match is to be found.  To reject matches that syntax
                highlighting recognized as strings:

     :echo searchpair('{', '', '}', 'bW',
          \ 'synIDattr(synID(line("."), col("."), 0), "name") =~? "string"')
 

                                                        *searchpairpos()*
searchpairpos({start}, {middle}, {end} [, {flags} [, {skip} [, {stopline}]]])
                Same as searchpair(), but returns a |List| with the line and
                column position of the match. The first element of the |List|
                is the line number and the second element is the byte index of
                the column position of the match.  If no match is found,
                returns [0, 0].

                     :let [lnum,col] = searchpairpos('{', '', '}', 'n')
 
                See |match-parens| for a bigger and more useful example.


searchpos({pattern} [, {flags} [, {stopline}]])         *searchpos()*
                Same as |search()|, but returns a |List| with the line and
                column position of the match. The first element of the |List|
                is the line number and the second element is the byte index of
                the column position of the match. If no match is found,
                returns [0, 0].
                Example:
     :let [lnum, col] = searchpos('mypattern', 'n')

                When the 'p' flag is given then there is an extra item with
                the sub-pattern match number |search()-sub-match|.  Example:
     :let [lnum, col, submatch] = searchpos('\(\l\)\|\(\u\)', 'np')
                In this example "submatch" is 2 when a lowercase letter is
                found |/\l|, 3 when an uppercase letter is found |/\u|.


server2client( {clientid}, {string})                    *server2client()*
                Send a reply string to {clientid}.  The most recent {clientid}
                that sent a string can be retrieved with expand("<client>").
                {only available when compiled with the |+clientserver| feature}
                Note:
                This id has to be stored before the next command can be
                received.  I.e. before returning from the received command and
                before calling any commands that waits for input.
                See also |clientserver|.
                Example:
                     :echo server2client(expand("<client>"), "HELLO")
 

serverlist()                                        *serverlist()*
                Return a list of available server names, one per line.
                When there are no servers or the information is not available
                an empty string is returned.  See also |clientserver|.
                {only available when compiled with the |+clientserver| feature}
                Example:
                     :echo serverlist()
 

setbufvar({expr}, {varname}, {val})                     *setbufvar()*
                Set option or local variable {varname} in buffer {expr} to
                {val}.
                This also works for a global or local window option, but it
                doesn't work for a global or local window variable.
                For a local window option the global value is unchanged.
                For the use of {expr}, see |bufname()| above.
                Note that the variable name without "b:" must be used.
                Examples:
                     :call setbufvar(1, "&mod", 1)
                     :call setbufvar("todo", "myvar", "foobar")
                This function is not available in the |sandbox|.


setcmdpos({pos})                                        *setcmdpos()*
                Set the cursor position in the command line to byte position
                {pos}.  The first position is 1.
                Use |getcmdpos()| to obtain the current position.
                Only works while editing the command line, thus you must use
                |c_CTRL-\_e|, |c_CTRL-R_=| or |c_CTRL-R_CTRL-R| with '='.  For
                |c_CTRL-\_e| and |c_CTRL-R_CTRL-R| with '=' the position is
                set after the command line is set to the expression.  For
                |c_CTRL-R_=| it is set after evaluating the expression but
                before inserting the resulting text.
                When the number is too big the cursor is put at the end of the
                line.  A number smaller than one has undefined results.
                Returns 0 when successful, 1 when not editing the command
                line.


setline({lnum}, {line})                                 *setline()*
                Set line {lnum} of the current buffer to {line}.
                {lnum} is used like with |getline()|.
                When {lnum} is just below the last line the {line} will be
                added as a new line.
                If this succeeds, 0 is returned.  If this fails (most likely
                because {lnum} is invalid) 1 is returned.  Example:
                     :call setline(5, strftime("%c"))
                When {line} is a |List| then line {lnum} and following lines
                will be set to the items in the list.  Example:
                     :call setline(5, ['aaa', 'bbb', 'ccc'])
                This is equivalent to:
                     :for [n, l] in [[5, 6, 7], ['aaa', 'bbb', 'ccc']]
                     :  call setline(n, l)
                     :endfor
                Note: The '[ and '] marks are not set.


setloclist({nr}, {list} [, {action}])                   *setloclist()*
                Create or replace or add to the location list for window {nr}.
                When {nr} is zero the current window is used. For a location
                list window, the displayed location list is modified.  For an
                invalid window number {nr}, -1 is returned.
                Otherwise, same as setqflist().


                                                        *setpos()*
setpos({expr}, {list})
                Set the position for {expr}.  Possible values:
                        .       the cursor
                        'x      mark x

                {list} must be a |List| with four numbers:
                    [bufnum, lnum, col, off]

                "bufnum" is the buffer number.  Zero can be used for the
                current buffer.  Setting the cursor is only possible for
                the current buffer.  To set a mark in another buffer you can
                use the |bufnr()| function to turn a file name into a buffer
                number.
                Does not change the jumplist.

                "lnum" and "col" are the position in the buffer.  The first
                column is 1.  Use a zero "lnum" to delete a mark.

                The "off" number is only used when 'virtualedit' is set. Then
                it is the offset in screen columns from the start of the
                character.  E.g., a position within a Tab or after the last
                character.

                Also see |getpos()|



setqflist({list} [, {action}])                          *setqflist()*
                Create or replace or add to the quickfix list using the items
                in {list}.  Each item in {list} is a dictionary.
                Non-dictionary items in {list} are ignored.  Each dictionary
                item can contain the following entries:

                    filename    name of a file
                    lnum        line number in the file
                    pattern  search pattern used to locate the error
                    col         column number
                    vcol        when non-zero: "col" is visual column
                                when zero: "col" is byte index
                    nr          error number
                    text        description of the error
                    type        single-character error type, 'E', 'W', etc.

                The "col", "vcol", "nr", "type" and "text" entries are
                optional.  Either "lnum" or "pattern" entry can be used to
                locate a matching error line.
                If the "filename" entry is not present or neither the "lnum"
                or "pattern" entries are present, then the item will not be
                handled as an error line.
                If both "pattern" and "lnum" are present then "pattern" will
                be used.

                If {action} is set to 'a', then the items from {list} are
                added to the existing quickfix list. If there is no existing
                list, then a new list is created. If {action} is set to 'r',
                then the items from the current quickfix list are replaced
                with the items from {list}. If {action} is not present or is
                set to '' '', then a new list is created.

                Returns zero for success, -1 for failure.

                This function can be used to create a quickfix list
                independent of the 'errorformat' setting.  Use a command like
                ":cc 1" to jump to the first position.



                                                        *setreg()*
setreg({regname}, {value} [,{options}])
                Set the register {regname} to {value}.
                If {options} contains "a" or {regname} is upper case,
                then the value is appended.
                {options} can also contains a register type specification:
                    "c" or "v"        |characterwise| mode
                    "l" or "V"        |linewise| mode
                    "b" or "<CTRL-V>" |blockwise-visual| mode
                If a number immediately follows "b" or "<CTRL-V>" then this is
                used as the width of the selection - if it is not specified
                then the width of the block is set to the number of characters
                in the longest line (counting a <TAB> as 1 character).

                If {options} contains no register settings, then the default
                is to use character mode unless {value} ends in a <NL>.
                Setting the '=' register is not possible.
                Returns zero for success, non-zero for failure.

                Examples:
                     :call setreg(v:register, @*)
                     :call setreg('*', @%, 'ac')
                     :call setreg('a', "1\n2\n3", 'b5')

                This example shows using the functions to save and restore a
                register.
                     :let var_a = getreg('a', 1)
                     :let var_amode = getregtype('a')
                         ....
                     :call setreg('a', var_a, var_amode)

                You can also change the type of a register by appending
                nothing:
                     :call setreg('a', '', 'al')


settabwinvar({tabnr}, {winnr}, {varname}, {val})        *settabwinvar()*
                Set option or local variable {varname} in window {winnr} to
                {val}.
                Tabs are numbered starting with one.  For the current tabpage
                use |setwinvar()|.
                When {winnr} is zero the current window is used.
                This also works for a global or local buffer option, but it
                doesn't work for a global or local buffer variable.
                For a local buffer option the global value is unchanged.
                Note that the variable name without "w:" must be used.
                Vim briefly goes to the tab page {tabnr}, this may trigger
                TabLeave and TabEnter autocommands.
                Examples:
                     :call settabwinvar(1, 1, "&list", 0)
                     :call settabwinvar(3, 2, "myvar", "foobar")
                This function is not available in the |sandbox|.


setwinvar({nr}, {varname}, {val})                       *setwinvar()*
                Like |settabwinvar()| for the current tab page.
                Examples:
                     :call setwinvar(1, "&list", 0)
                     :call setwinvar(2, "myvar", "foobar")


simplify({filename})                                    *simplify()*
                Simplify the file name as much as possible without changing
                the meaning.  Shortcuts (on MS-Windows) or symbolic links (on
                Unix) are not resolved.  If the first path component in
                {filename} designates the current directory, this will be
                valid for the result as well.  A trailing path separator is
                not removed either.
                Example:
                     simplify("./dir/.././/file/") == "./file/"
                Note: The combination "dir/.." is only removed if "dir" is
                a searchable directory or does not exist.  On Unix, it is also
                removed when "dir" is a symbolic link within the same
                directory.  In order to resolve all the involved symbolic
                links before simplifying the path name, use |resolve()|.



sort({list} [, {func}])                                 *sort()* *E702*
                Sort the items in {list} in-place.  Returns {list}.  If you
                want a list to remain unmodified make a copy first:
                     :let sortedlist = sort(copy(mylist))
                Uses the string representation of each item to sort on.
                Numbers sort after Strings, |Lists| after Numbers.
                For sorting text in the current buffer use |:sort|.
                When {func} is given and it is one then case is ignored.
                When {func} is a |Funcref| or a function name, this function
                is called to compare items.  The function is invoked with two
                items as argument and must return zero if they are equal, 1 if
                the first one sorts after the second one, -1 if the first one
                sorts before the second one.  Example:
                     func MyCompare(i1, i2)
                        return a:i1 == a:i2 ? 0 : a:i1 > a:i2 ? 1 : -1
                     endfunc
                     let sortedlist = sort(mylist, "MyCompare")
 


                                                        *soundfold()*
soundfold({word})
                Return the sound-folded equivalent of {word}.  Uses the first
                language in 'spellang' for the current window that supports
                soundfolding.  'spell' must be set.  When no sound folding is
                possible the {word} is returned unmodified.
                This can be used for making spelling suggestions.  Note that
                the method can be quite slow.


                                                        *spellbadword()*
spellbadword([{sentence}])
                Without argument: The result is the badly spelled word under
                or after the cursor.  The cursor is moved to the start of the
                bad word.  When no bad word is found in the cursor line the
                result is an empty string and the cursor doesn't move.

                With argument: The result is the first word in {sentence} that
                is badly spelled.  If there are no spelling mistakes the
                result is an empty string.

                The return value is a list with two items:
                - The badly spelled word or an empty string.
                - The type of the spelling error:
                        "bad"         spelling mistake
                        "rare"                rare word
                        "local"               word only valid in another region
                        "caps"                word should start with Capital
                Example:
                     echo spellbadword("the quik brown fox")
                        ['quik', 'bad'] 

                The spelling information for the current window is used.  The
                'spell' option must be set and the value of 'spelllang' is
                used.


                                                        *spellsuggest()*
spellsuggest({word} [, {max} [, {capital}]])
                Return a |List| with spelling suggestions to replace {word}.
                When {max} is given up to this number of suggestions are
                returned.  Otherwise up to 25 suggestions are returned.

                When the {capital} argument is given and it's non-zero only
                suggestions with a leading capital will be given.  Use this
                after a match with 'spellcapcheck'.

                {word} can be a badly spelled word followed by other text.
                This allows for joining two words that were split.  The
                suggestions also include the following text, thus you can
                replace a line.

                {word} may also be a good word.  Similar words will then be
                returned.  {word} itself is not included in the suggestions,
                although it may appear capitalized.

                The spelling information for the current window is used.  The
                'spell' option must be set and the values of 'spelllang' and
                'spellsuggest' are used.



split({expr} [, {pattern} [, {keepempty}]])                     *split()*
                Make a |List| out of {expr}.  When {pattern} is omitted or
                empty each white-separated sequence of characters becomes an
                item.
                Otherwise the string is split where {pattern} matches,
                removing the matched characters.
                When the first or last item is empty it is omitted, unless the
                {keepempty} argument is given and it's non-zero.
                Other empty items are kept when {pattern} matches at least one
                character or when {keepempty} is non-zero.
                Example:
                     :let words = split(getline('.'), '\W\+')
                To split a string in individual characters:
                     :for c in split(mystring, '\zs')
                If you want to keep the separator you can also use '\zs':
                     :echo split('abc:def:ghi', ':\zs')
                        ['abc:', 'def:', 'ghi'] 
                Splitting a table where the first element can be empty:
                     :let items = split(line, ':', 1)
                The opposite function is |join()|.



str2nr( {expr} [, {base}])                              *str2nr()*
                Convert string {expr} to a number.
                {base} is the conversion base, it can be 8, 10 or 16.
                When {base} is omitted base 10 is used.  This also means that
                a leading zero doesn't cause octal conversion to be used, as
                with the default String to Number conversion.
                When {base} is 16 a leading "0x" or "0X" is ignored.  With a
                different base the result will be zero.
                Text after the number is silently ignored.



strftime({format} [, {time}])                           *strftime()*
                The result is a String, which is a formatted date and time, as
                specified by the {format} string.  The given {time} is used,
                or the current time if no time is given.  The accepted
                {format} depends on your system, thus this is not portable!
                See the manual page of the C function strftime() for the
                format.  The maximum length of the result is 80 characters.
                See also |localtime()| and |getftime()|.
                The language can be changed with the |:language| command.
                Examples:
               :echo strftime("%c")             Sun Apr 27 11:49:23 1997
               :echo strftime("%Y %b %d %X")    1997 Apr 27 11:53:25
               :echo strftime("%y%m%d %T")      970427 11:53:55
               :echo strftime("%H:%M")          11:55
               :echo strftime("%c", getftime("file.c"))
                                                Show mod time of file.c.
                Not available on all systems.  To check use:
                     :if exists("*strftime")


stridx({haystack}, {needle} [, {start}])                *stridx()*
                The result is a Number, which gives the byte index in
                {haystack} of the first occurrence of the String {needle}.
                If {start} is specified, the search starts at index {start}.
                This can be used to find a second match:
                     :let comma1 = stridx(line, ",")
                     :let comma2 = stridx(line, ",", comma1 + 1)
                The search is done case-sensitive.
                For pattern searches use |match()|.
                -1 is returned if the {needle} does not occur in {haystack}.
                See also |strridx()|.
                Examples:
               :echo stridx("An Example", "Example")      3
               :echo stridx("Starting point", "Start")    0
               :echo stridx("Starting point", "start")   -1

                                                *strstr()* *strchr()*
                stridx() works similar to the C function strstr().  When used
                with a single character it works similar to strchr().


                                                        *string()*
string({expr})  Return {expr} converted to a String.  If {expr} is a Number,
                String or a composition of them, then the result can be parsed
                back with |eval()|.
                        {expr} type     result 
                        String          'string'
                        Number          123
                        Funcref          function('name')
                        List                [item, item]
                        Dictionary    {key: value, key: value}
                Note that in String values the '' character is doubled.


                                                        *strlen()*
strlen({expr})  The result is a Number, which is the length of the String
                {expr} in bytes.
                If you want to count the number of multi-byte characters (not
                counting composing characters) use something like this:

                     :let len = strlen(substitute(str, ".", "x", "g"))
 
                If the argument is a Number it is first converted to a String.
                For other types an error is given.
                Also see |len()|.


strpart({src}, {start}[, {len}])                        *strpart()*
                The result is a String, which is part of {src}, starting from
                byte {start}, with the byte length {len}.
                When non-existing bytes are included, this doesn't result in
                an error, the bytes are simply omitted.
                If {len} is missing, the copy continues from {start} till the
                end of the {src}.
                     strpart("abcdefg", 3, 2)    == "de"
                     strpart("abcdefg", -2, 4)   == "ab"
                     strpart("abcdefg", 5, 4)    == "fg"
                     strpart("abcdefg", 3)       == "defg"
                Note: To get the first character, {start} must be 0.  For
                example, to get three bytes under and after the cursor:
                     strpart(getline("."), col(".") - 1, 3)
 

strridx({haystack}, {needle} [, {start}])                       *strridx()*
                The result is a Number, which gives the byte index in
                {haystack} of the last occurrence of the String {needle}.
                When {start} is specified, matches beyond this index are
                ignored.  This can be used to find a match before a previous
                match:
                     :let lastcomma = strridx(line, ",")
                     :let comma2 = strridx(line, ",", lastcomma - 1)
                The search is done case-sensitive.
                For pattern searches use |match()|.
                -1 is returned if the {needle} does not occur in {haystack}.
                If the {needle} is empty the length of {haystack} is returned.
                See also |stridx()|.  Examples:
               :echo strridx("an angry armadillo", "an")          3

                                                        *strrchr()*
                When used with a single character it works similar to the C
                function strrchr().


strtrans({expr})                                        *strtrans()*
                The result is a String, which is {expr} with all unprintable
                characters translated into printable characters |'isprint'|.
                Like they are shown in a window.  Example:
                     echo strtrans(@a)
                This displays a newline in register a as "^@" instead of
                starting a new line.


submatch({nr})                                          *submatch()*
                Only for an expression in a |:substitute| command.  Returns
                the {nr}'th submatch of the matched text.  When {nr} is 0
                the whole matched text is returned.
                Example:
                     :s/\d\+/\=submatch(0) + 1/
                This finds the first number in the line and adds one to it.
                A line break is included as a newline character.


substitute({expr}, {pat}, {sub}, {flags})              *substitute()*
                The result is a String, which is a copy of {expr}, in which
                the first match of {pat} is replaced with {sub}.  This works
                like the ":substitute" command (without any flags).  But the
                matching with {pat} is always done like the 'magic' option is
                set and 'cpoptions' is empty (to make scripts portable).
                'ignorecase' is still relevant.
                See |string-match| for how {pat} is used.
                And a "~" in {sub} is not replaced with the previous {sub}.
                Note that some codes in {sub} have a special meaning
                |sub-replace-special|.  For example, to replace something with
                "\n" (two characters), use "\\\\n" or '\\n'.
                When {pat} does not match in {expr}, {expr} is returned
                unmodified.
                When {flags} is "g", all matches of {pat} in {expr} are
                replaced.  Otherwise {flags} should be "".
                Example:
                     :let &path = substitute(&path, ",\\=[^,]*$", "", "")
                This removes the last component of the 'path' option.
                     :echo substitute("testing", ".*", "\\U\\0", "")
                results in "TESTING".


synID({lnum}, {col}, {trans})                           *synID()*
                The result is a Number, which is the syntax ID at the position
                {lnum} and {col} in the current window.
                The syntax ID can be used with |synIDattr()| and
                |synIDtrans()| to obtain syntax information about text.

                {col} is 1 for the leftmost column, {lnum} is 1 for the first
                line.  'synmaxcol' applies, in a longer line zero is returned.

                When {trans} is non-zero, transparent items are reduced to the
                item that they reveal.  This is useful when wanting to know
                the effective color.  When {trans} is zero, the transparent
                item is returned.  This is useful when wanting to know which
                syntax item is effective (e.g. inside parens).
                Warning: This function can be very slow.  Best speed is
                obtained by going through the file in forward direction.

                Example (echoes the name of the syntax item under the cursor):
                     :echo synIDattr(synID(line("."), col("."), 1), "name")
 

synIDattr({synID}, {what} [, {mode}])                   *synIDattr()*
                The result is a String, which is the {what} attribute of
                syntax ID {synID}.  This can be used to obtain information
                about a syntax item.
                {mode} can be "gui", "cterm" or "term", to get the attributes
                for that mode.  When {mode} is omitted, or an invalid value is
                used, the attributes for the currently active highlighting are
                used (GUI, cterm or term).
                Use synIDtrans() to follow linked highlight groups.
                {what}          result
                "name"                the name of the syntax item
                "fg"          foreground color (GUI: color name used to set
                                the color, cterm: color number as a string,
                                term: empty string)
                "bg"          background color (like "fg")
                "fg#"         like "fg", but for the GUI and the GUI is
                                running the name in "#RRGGBB" form
                "bg#"         like "fg#" for "bg"
                "bold"         "1" if bold
                "italic"     "1" if italic
                "reverse"     "1" if reverse
                "inverse"   "1" if inverse (= reverse)
                "underline"       "1" if underlined
                "undercurl"       "1" if undercurled

                Example (echoes the color of the syntax item under the
                cursor):
     :echo synIDattr(synIDtrans(synID(line("."), col("."), 1)), "fg")
 

synIDtrans({synID})                                     *synIDtrans()*
                The result is a Number, which is the translated syntax ID of
                {synID}.  This is the syntax group ID of what is being used to
                highlight the character.  Highlight links given with
                ":highlight link" are followed.


system({expr} [, {input}])                              *system()* *E677*
                Get the output of the shell command {expr}.
                When {input} is given, this string is written to a file and
                passed as stdin to the command.  The string is written as-is,
                you need to take care of using the correct line separators
                yourself.  Pipes are not used.
                Note: newlines in {expr} may cause the command to fail.  The
                characters in 'shellquote' and 'shellxquote' may also cause
                trouble.
                This is not to be used for interactive commands.
                The result is a String.  Example:

                     :let files = system("ls")

                To make the result more system-independent, the shell output
                is filtered to replace <CR> with <NL> for Macintosh, and
                <CR><NL> with <NL> for DOS-like systems.
                The command executed is constructed using several options:
        'shell' 'shellcmdflag' 'shellxquote' {expr} 'shellredir' {tmp} 'shellxquote'
                ({tmp} is an automatically generated file name).
                For Unix and OS/2 braces are put around {expr} to allow for
                concatenated commands.

                The command will be executed in "cooked" mode, so that a
                CTRL-C will interrupt the command (on Unix at least).

                The resulting error code can be found in |v:shell_error|.
                This function will fail in |restricted-mode|.

                Note that any wrong value in the options mentioned above may
                make the function fail.  It has also been reported to fail
                when using a security agent application.
                Unlike ":!cmd" there is no automatic check for changed files.
                Use |:checktime| to force a check.



tabpagebuflist([{arg}])                                 *tabpagebuflist()*
                The result is a |List|, where each item is the number of the
                buffer associated with each window in the current tab page.
                {arg} specifies the number of tab page to be used.  When
                omitted the current tab page is used.
                When {arg} is invalid the number zero is returned.
                To get a list of all buffers in all tabs use this:
                     tablist = []
                     for i in range(tabpagenr('$'))
                        call extend(tablist, tabpagebuflist(i + 1))
                     endfor
                Note that a buffer may appear in more than one window.



tabpagenr([{arg}])                                      *tabpagenr()*
                The result is a Number, which is the number of the current
                tab page.  The first tab page has number 1.
                When the optional argument is "$", the number of the last tab
                page is returned (the tab page count).
                The number can be used with the |:tab| command.



tabpagewinnr({tabarg}, [{arg}])                         *tabpagewinnr()*
                Like |winnr()| but for tab page {arg}.
                {tabarg} specifies the number of tab page to be used.
                {arg} is used like with YXXYwinnr()|:
                - When omitted the current window number is returned.  This is
                  the window which will be used when going to this tab page.
                - When "$" the number of windows is returned.
                - When "#" the previous window nr is returned.
                Useful examples:
                 tabpagewinnr(1)         " current window of tab page 1
                 tabpagewinnr(4, '$')    " number of windows in tab page 4
                When {tabarg} is invalid zero is returned.


                                                        *tagfiles()*
tagfiles()    Returns a |List| with the file names used to search for tags
                for the current buffer.  This is the 'tags' option expanded.



taglist({expr})                                                 *taglist()*
                Returns a list of tags matching the regular expression {expr}.
                Each list item is a dictionary with at least the following
                entries:
                        name            Name of the tag.
                        filename        Name of the file where the tag is
                                        defined.
                        cmd             Ex command used to locate the tag in
                                        the file.
                        kind            Type of the tag.  The value for this
                                        entry depends on the language specific
                                        kind values generated by the ctags
                                        tool.
                        static          A file specific tag.  Refer to
                                        |static-tag| for more information.
                The "kind" entry is only available when using Exuberant ctags
                generated tags file.  More entries may be present, depending
                on the content of the tags file: access, implementation,
                inherits and signature.  Refer to the ctags documentation for
                information about these fields.  For C code the fields
                "struct", "class" and "enum" may appear, they give the name of
                the entity the tag is contained in.

                The ex-command 'cmd' can be either an ex search pattern, a
                line number or a line number followed by a byte number.

                If there are no matching tags, then an empty list is returned.

                To get an exact tag match, the anchors '^' and '$' should be
                used in {expr}.  Refer to |tag-regexp| for more information
                about the tag search regular expression pattern.

                Refer to |'tags'| for information about how the tags file is
                located by Vim. Refer to |tags-file-format| for the format of
                the tags file generated by the different ctags tools.


tempname()                                    *tempname()* *temp-file-name*
                The result is a String, which is the name of a file that
                doesn't exist.  It can be used for a temporary file.  The name
                is different for at least 26 consecutive calls.  Example:
                     :let tmpfile = tempname()
                     :exe "redir > " . tmpfile
                For Unix, the file will be in a private directory (only
                accessible by the current user) to avoid security problems
                (e.g., a symlink attack or other people reading your file).
                When Vim exits the directory and all files in it are deleted.
                For MS-Windows forward slashes are used when the 'shellslash'
                option is set or when 'shellcmdflag' starts with '-'.


tolower({expr})                                         *tolower()*
                The result is a copy of the String given, with all uppercase
                characters turned into lowercase (just like applying |gu| to
                the string).


toupper({expr})                                         *toupper()*
                The result is a copy of the String given, with all lowercase
                characters turned into uppercase (just like applying |gU| to
                the string).


tr({src}, {fromstr}, {tostr})                           *tr()*
                The result is a copy of the {src} string with all characters
                which appear in {fromstr} replaced by the character in that
                position in the {tostr} string.  Thus the first character in
                {fromstr} is translated into the first character in {tostr}
                and so on.  Exactly like the unix "tr" command.
                This code also deals with multibyte characters properly.

                Examples:
                     echo tr("hello there", "ht", "HT")
                returns "Hello THere"
                     echo tr("<blob>", "<>", "{}")
                returns "{blob}"


                                                        *type()*
type({expr})    The result is a Number, depending on the type of {expr}:
                        Number:     0
                        String:     1
                        Funcref:    2
                        List:           3
                        Dictionary: 4
                To avoid the magic numbers it should be used this way:
                     :if type(myvar) == type(0)
                     :if type(myvar) == type("")
                     :if type(myvar) == type(function("tr"))
                     :if type(myvar) == type([])
                     :if type(myvar) == type({})


values({dict})                                          *values()*
                Return a |List| with all the values of {dict}.  The |List| is
                in arbitrary order.



virtcol({expr})                                         *virtcol()*
                The result is a Number, which is the screen column of the file
                position given with {expr}.  That is, the last screen position
                occupied by the character at that position, when the screen
                would be of unlimited width.  When there is a <Tab> at the
                position, the returned Number will be the column at the end of
                the <Tab>.  For example, for a <Tab> in column 1, with 'ts'
                set to 8, it returns 8.
                For the use of {expr} see |col()|.  Additionally you can use
                [lnum, col]: a |List| with the line and column number.  When
                "lnum" or "col" is out of range then virtcol() returns zero.
                When 'virtualedit' is used it can be [lnum, col, off], where
                "off" is the offset in screen columns from the start of the
                character.  E.g., a position within a Tab or after the last
                character.
                For the byte position use |col()|.
                When Virtual editing is active in the current mode, a position
                beyond the end of the line can be returned. |'virtualedit'|
                The accepted positions are:
                    .       the cursor position
                    $       the end of the cursor line (the result is the
                            number of displayed characters in the cursor line
                            plus one)
                    'x      position of mark x (if the mark is not set, 0 is
                            returned)
                Note that only marks in the current file can be used.
                Examples:
  virtcol(".")          with text "foo^Lbar", with cursor on the "^L", returns 5
  virtcol("$")          with text "foo^Lbar", returns 9
  virtcol("'t")    with text "    there", with 't at 'h', returns 6
                The first column is 1.  0 is returned for an error.


visualmode([expr])                                              *visualmode()*
                The result is a String, which describes the last Visual mode
                used in the current buffer.  Initially it returns an empty
                string, but once Visual mode has been used, it returns "v",
                "V", or "<CTRL-V>" (a single CTRL-V character) for
                character-wise, line-wise, or block-wise Visual mode
                respectively.
                Example:
                     :exe "normal " . visualmode()
                This enters the same Visual mode as before.  It is also useful
                in scripts if you wish to act differently depending on the
                Visual mode that was used.

                If an expression is supplied that results in a non-zero number
                or a non-empty string, then the Visual mode will be cleared
                and the old value is returned.  Note that " " and "0" are also
                non-empty strings, thus cause the mode to be cleared.


                                                        *winbufnr()*
winbufnr({nr})  The result is a Number, which is the number of the buffer
                associated with window {nr}.  When {nr} is zero, the number of
                the buffer in the current window is returned.  When window
                {nr} doesn't exist, -1 is returned.
                Example:
  :echo "The file in the current window is " . bufname(winbufnr(0))
 

                                                        *wincol()*
wincol()        The result is a Number, which is the virtual column of the
                cursor in the window.  This is counting screen cells from the
                left side of the window.  The leftmost column is one.


winheight({nr})                                         *winheight()*
                The result is a Number, which is the height of window {nr}.
                When {nr} is zero, the height of the current window is
                returned.  When window {nr} doesn't exist, -1 is returned.
                An existing window always has a height of zero or more.
                Examples:
  :echo "The current window has " . winheight(0) . " lines."
 

                                                        *winline()*
winline()      The result is a Number, which is the screen line of the cursor
                in the window.  This is counting screen lines from the top of
                the window.  The first line is one.
                If the cursor was moved the view on the file will be updated
                first, this may cause a scroll.


                                                        *winnr()*
winnr([{arg}])  The result is a Number, which is the number of the current
                window.  The top window has number 1.
                When the optional argument is "$", the number of the
                last window is returned (the window count).
                When the optional argument is "#", the number of the last
                accessed window is returned (where |CTRL-W_p| goes to).
                If there is no previous window 0 is returned.
                The number can be used with |CTRL-W_w| and ":wincmd w"
                |:wincmd|.


                                                        *winrestcmd()*
winrestcmd()        Returns a sequence of |:resize| commands that should restore
                the current window sizes.  Only works properly when no windows
                are opened or closed and the current window and tab page is
                unchanged.
                Example:
                     :let cmd = winrestcmd()
                     :call MessWithWindowSizes()
                     :exe cmd
 

                                                        *winrestview()*
winrestview({dict})
                Uses the |Dictionary| returned by |winsaveview()| to restore
                the view of the current window.
                If you have changed the values the result is unpredictable.
                If the window size changed the result won't be the same.


                                                        *winsaveview()*
winsaveview()      Returns a |Dictionary| that contains information to restore
                the view of the current window.  Use |winrestview()| to
                restore the view.
                This is useful if you have a mapping that jumps around in the
                buffer and you want to go back to the original view.
                This does not save fold information.  Use the 'foldenable'
                option to temporarily switch off folding, so that folds are
                not opened when moving around.
                The return value includes:
                        lnum            cursor line number
                        col             cursor column
                        coladd          cursor column offset for 'virtualedit'
                        curswant        column for vertical movement
                        topline         first line in the window
                        topfill         filler lines, only in diff mode
                        leftcol         first column displayed
                        skipcol         columns skipped
                Note that no option values are saved.



winwidth({nr})                                          *winwidth()*
                The result is a Number, which is the width of window {nr}.
                When {nr} is zero, the width of the current window is
                returned.  When window {nr} doesn't exist, -1 is returned.
                An existing window always has a width of zero or more.
                Examples:
  :echo "The current window has " . winwidth(0) . " columns."
  :if winwidth(0) <= 50
  :  exe "normal 50\<C-W>|"
  :endif
 

                                                        *writefile()*
writefile({list}, {fname} [, {binary}])
                Write |List| {list} to file {fname}.  Each list item is
                separated with a NL.  Each list item must be a String or
                Number.
                When {binary} is equal to "b" binary mode is used: There will
                not be a NL after the last list item.  An empty item at the
                end does cause the last line in the file to end in a NL.
                All NL characters are replaced with a NUL character.
                Inserting CR characters needs to be done before passing {list}
                to writefile().
                An existing file is overwritten, if possible.
                When the write fails -1 is returned, otherwise 0.  There is an
                error message if the file can't be created or when writing
                fails.
                Also see |readfile()|.
                To copy a file byte for byte:
                     :let fl = readfile("foo", "b")
                     :call writefile(fl, "foocopy", "b")
 


                                                        *feature-list*
There are three types of features:
1.  Features that are only supported when they have been enabled when Vim
    was compiled |+feature-list|.  Example:
     :if has("cindent")
2.  Features that are only supported when certain conditions have been met.
    Example:
     :if has("gui_running")

                                                        *has-patch*
3.  Included patches.  First check |v:version| for the version of Vim.
    Then the "patch123" feature means that patch 123 has been included for
    this version.  Example (checking version 6.2.148 or later):
     :if v:version > 602 || v:version == 602 && has("patch148")

all_builtin_terms       Compiled with all builtin terminals enabled.
amiga                   Amiga version of Vim.
arabic                  Compiled with Arabic support |Arabic|.
arp                     Compiled with ARP support (Amiga).
autocmd                 Compiled with autocommand support. |autocommand|
balloon_eval            Compiled with |balloon-eval| support.
balloon_multiline       GUI supports multiline balloons.
beos                    BeOS version of Vim.
browse                  Compiled with |:browse| support, and browse() will
                        work.
builtin_terms             Compiled with some builtin terminals.
byte_offset             Compiled with support for 'o' in 'statusline'
cindent                 Compiled with 'cindent' support.
clientserver            Compiled with remote invocation support |clientserver|.
clipboard              Compiled with 'clipboard' support.
cmdline_compl           Compiled with |cmdline-completion| support.
cmdline_hist            Compiled with |cmdline-history| support.
cmdline_info            Compiled with 'showcmd' and 'ruler' support.
comments                Compiled with |'comments'| support.
cryptv                  Compiled with encryption support |encryption|.
cscope                  Compiled with |cscope| support.
compatible              Compiled to be very Vi compatible.
debug                   Compiled with "DEBUG" defined.
dialog_con              Compiled with console dialog support.
dialog_gui              Compiled with GUI dialog support.
diff                    Compiled with |vimdiff| and 'diff' support.
digraphs            Compiled with support for digraphs.
dnd                     Compiled with support for the "~ register |quote_~|.
dos32                 32 bits DOS (DJGPP) version of Vim.
dos16                 16 bits DOS version of Vim.
ebcdic                  Compiled on a machine with ebcdic character set.
emacs_tags                Compiled with support for Emacs tags.
eval                        Compiled with expression evaluation support.  Always
                        true, of course!
ex_extra                Compiled with extra Ex commands |+ex_extra|.
extra_search            Compiled with support for |'incsearch'| and
                        |'hlsearch'|
farsi                   Compiled with Farsi support |farsi|.
file_in_path            Compiled with support for |gf| and |<cfile>|
filterpipe              When 'shelltemp' is off pipes are used for shell
                        read/write/filter commands
find_in_path            Compiled with support for include file searches
                        |+find_in_path|.
fname_case              Case in file names matters (for Amiga, MS-DOS, and
                        Windows this is not present).
folding                 Compiled with |folding| support.
footer                  Compiled with GUI footer support. |gui-footer|
fork                    Compiled to use fork()/exec() instead of system().
gettext                 Compiled with message translation |multi-lang|
gui                  Compiled with GUI enabled.
gui_athena              Compiled with Athena GUI.
gui_gtk                 Compiled with GTK+ GUI (any version).
gui_gtk2                Compiled with GTK+ 2 GUI (gui_gtk is also defined).
gui_mac                 Compiled with Macintosh GUI.
gui_motif               Compiled with Motif GUI.
gui_photon              Compiled with Photon GUI.
gui_win32               Compiled with MS Windows Win32 GUI.
gui_win32s              idem, and Win32s system being used (Windows 3.1)
gui_running             Vim is running in the GUI, or it will start soon.
hangul_input            Compiled with Hangul input support. |hangul|
iconv                   Can use iconv() for conversion.
insert_expand           Compiled with support for CTRL-X expansion commands in
                        Insert mode.
jumplist                Compiled with |jumplist| support.
keymap                  Compiled with 'keymap' support.
langmap                 Compiled with 'langmap' support.
libcall                 Compiled with |libcall()| support.
linebreak               Compiled with 'linebreak', 'breakat' and 'showbreak'
                        support.
lispindent              Compiled with support for lisp indenting.
listcmds                Compiled with commands for the buffer list |:files|
                        and the argument list |arglist|.
localmap                Compiled with local mappings and abbr. |:map-local|
mac                       Macintosh version of Vim.
macunix                 Macintosh version of Vim, using Unix files (OS-X).
menu                    Compiled with support for |:menu|.
mksession               Compiled with support for |:mksession|.
modify_fname            Compiled with file name modifiers. |filename-modifiers|
mouse                   Compiled with support mouse.
mouseshape              Compiled with support for 'mouseshape'.
mouse_dec               Compiled with support for Dec terminal mouse.
mouse_gpm               Compiled with support for gpm (Linux console mouse)
mouse_netterm           Compiled with support for netterm mouse.
mouse_pterm             Compiled with support for qnx pterm mouse.
mouse_xterm             Compiled with support for xterm mouse.
multi_byte              Compiled with support for editing Korean et al.
multi_byte_ime          Compiled with support for IME input method.
multi_lang              Compiled with support for multiple languages.
mzscheme                Compiled with MzScheme interface |mzscheme|.
netbeans_intg           Compiled with support for |netbeans|.
netbeans_enabled        Compiled with support for |netbeans| and it's used.
ole                     Compiled with OLE automation support for Win32.
os2                       OS/2 version of Vim.
osfiletype              Compiled with support for osfiletypes |+osfiletype|
path_extra              Compiled with up/downwards search in 'path' and 'tags'
perl                    Compiled with Perl interface.
postscript              Compiled with PostScript file printing.
printer                 Compiled with |:hardcopy| support.
profile                 Compiled with |:profile| support.
python                        Compiled with Python interface.
qnx                       QNX version of Vim.
quickfix                Compiled with |quickfix| support.
reltime                 Compiled with |reltime()| support.
rightleft               Compiled with 'rightleft' support.
ruby                    Compiled with Ruby interface |ruby|.
scrollbind              Compiled with 'scrollbind' support.
showcmd                 Compiled with 'showcmd' support.
signs                     Compiled with |:sign| support.
smartindent             Compiled with 'smartindent' support.
sniff                 Compiled with SNiFF interface support.
statusline              Compiled with support for 'statusline', 'rulerformat'
                        and special formats of 'titlestring' and 'iconstring'.
sun_workshop            Compiled with support for Sun |workshop|.
spell                   Compiled with spell checking support |spell|.
syntax                  Compiled with syntax highlighting support |syntax|.
syntax_items            There are active syntax highlighting items for the
                        current buffer.
system                  Compiled to use system() instead of fork()/exec().
tag_binary              Compiled with binary searching in tags files
                        |tag-binary-search|.
tag_old_static          Compiled with support for old static tags
                        |tag-old-static|.
tag_any_white           Compiled with support for any white characters in tags
                        files |tag-any-white|.
tcl                       Compiled with Tcl interface.
terminfo               Compiled with terminfo instead of termcap.
termresponse            Compiled with support for |t_RV| and |v:termresponse|.
textobjects             Compiled with support for |text-objects|.
tgetent                 Compiled with tgetent support, able to use a termcap
                        or terminfo file.
title                   Compiled with window title support |'title'|.
toolbar                 Compiled with support for |gui-toolbar|.
unix                    Unix version of Vim.
user_commands           User-defined commands.
viminfo                     Compiled with viminfo support.
vim_starting            True while initial source'ing takes place.
vertsplit               Compiled with vertically split windows |:vsplit|.
virtualedit             Compiled with 'virtualedit' option.
visual                  Compiled with Visual mode.
visualextra             Compiled with extra Visual mode commands.
                        |blockwise-operators|.
vms                       VMS version of Vim.
vreplace                Compiled with |gR| and |gr| commands.
wildignore              Compiled with 'wildignore' option.
wildmenu                Compiled with 'wildmenu' option.
windows                      Compiled with support for more than one window.
winaltkeys              Compiled with 'winaltkeys' option.
win16                   Win16 version of Vim (MS-Windows 3.1).
win32                 Win32 version of Vim (MS-Windows 95/98/ME/NT/2000/XP).
win64                   Win64 version of Vim (MS-Windows 64 bit).
win32unix               Win32 version of Vim, using Unix files (Cygwin)
win95                   Win32 version for MS-Windows 95/98/ME.
writebackup             Compiled with 'writebackup' default on.
xfontset                Compiled with X fontset support |xfontset|.
xim                     Compiled with X input method support |xim|.
xsmp                    Compiled with X session management support.
xsmp_interact           Compiled with interactive X session management support.
xterm_clipboard         Compiled with support for xterm clipboard.
xterm_save              Compiled with support for saving and restoring the
                        xterm screen.
x11                     Compiled with X11 support.


                                                        *string-match*
Matching a pattern in a String

A regexp pattern as explained at |pattern| is normally used to find a match in
the buffer lines.  When a pattern is used to find a match in a String, almost
everything works in the same way.  The difference is that a String is handled
like it is one line.  When it contains a "\n" character, this is not seen as a
line break for the pattern.  It can be matched with a "\n" in the pattern, or
with ".".  Example:
     :let a = "aaaa\nxxxx"
     :echo matchstr(a, "..\n..")
     aa
     xx
     :echo matchstr(a, "a.x")
     a
     x

Don't forget that "^" will only match at the first character of the String and
"$" at the last character of the string.  They don't match after or before a
"\n".

==============================================================================

5. Defining functions                                  *user-functions*

New functions can be defined.  These can be called just like builtin
functions.  The function executes a sequence of Ex commands.  Normal mode
commands can be executed with the |:normal| command.

The function name must start with an uppercase letter, to avoid confusion with
builtin functions.  To prevent from using the same name in different scripts
avoid obvious, short names.  A good habit is to start the function name with
the name of the script, e.g., "HTMLcolor()".

It's also possible to use curly braces, see |curly-braces-names|.  And the
|autoload| facility is useful to define a function only when it's called.


                                                        *local-function*
A function local to a script must start with "s:".  A local script function
can only be called from within the script and from functions, user commands
and autocommands defined in the script.  It is also possible to call the
function from a mappings defined in the script, but then |<SID>| must be used
instead of "s:" when the mapping is expanded outside of the script.


                                        *:fu* *:function* *E128* *E129* *E123*
:fu[nction]             List all functions and their arguments.

:fu[nction] {name}      List function {name}.
                        {name} can also be a |Dictionary| entry that is a
                        YXXYFuncref|:
                             :function dict.init

:fu[nction] /{pattern}  List functions with a name matching {pattern}.
                        Example that lists all functions ending with "File":
                             :function /File$
 

                                                        *:function-verbose*
When 'verbose' is non-zero, listing a function will also display where it was
last defined. Example:

    :verbose function SetFileTypeSH
     function SetFileTypeSH(name)
         Last set from /usr/share/vim/vim-7.0/filetype.vim
 
See |:verbose-cmd| for more information.


                                                        *E124* *E125*
:fu[nction][!] {name}([arguments]) [range] [abort] [dict]
                        Define a new function by the name {name}.  The name
                        must be made of alphanumeric characters and '_', and
                        must start with a capital or "s:" (see above).

                        {name} can also be a |Dictionary| entry that is a
                        YXXYFuncref|:
                             :function dict.init(arg)
                        "dict" must be an existing dictionary.  The entry
                        "init" is added if it didn't exist yet.  Otherwise [!]
                        is required to overwrite an existing function.  The
                        result is a |Funcref| to a numbered function.  The
                        function can only be used with a |Funcref| and will be
                        deleted if there are no more references to it.

                                                                *E127* *E122*
                        When a function by this name already exists and [!] is
                        not used an error message is given.  When [!] is used,
                        an existing function is silently replaced.  Unless it
                        is currently being executed, that is an error.

                        For the {arguments} see |function-argument|.


                                                *a:firstline* *a:lastline*
                        When the [range] argument is added, the function is
                        expected to take care of a range itself.  The range is
                        passed as "a:firstline" and "a:lastline".  If [range]
                        is excluded, ":{range}call" will call the function for
                        each line in the range, with the cursor on the start
                        of each line.  See |function-range-example|.

                        When the [abort] argument is added, the function will
                        abort as soon as an error is detected.

                        When the [dict] argument is added, the function must
                        be invoked through an entry in a |Dictionary|.  The
                        local variable "self" will then be set to the
                        dictionary.  See |Dictionary-function|.

                        The last used search pattern and the redo command "."
                        will not be changed by the function.


                                        *:endf* *:endfunction* *E126* *E193*
:endf[unction]          The end of a function definition.  Must be on a line
                        by its own, without other commands.


                                        *:delf* *:delfunction* *E130* *E131*
:delf[unction] {name}   Delete function {name}.
                        {name} can also be a |Dictionary| entry that is a
                        YXXYFuncref|:
                             :delfunc dict.init
                        This will remove the "init" entry from "dict".  The
                        function is deleted if there are no more references to
                        it.

                                                        *:retu* *:return* *E133*
:retu[rn] [expr]        Return from a function.  When "[expr]" is given, it is
                        evaluated and returned as the result of the function.
                        If "[expr]" is not given, the number 0 is returned.
                        When a function ends without an explicit ":return",
                        the number 0 is returned.
                        Note that there is no check for unreachable lines,
                        thus there is no warning if commands follow ":return".

                        If the ":return" is used after a |:try| but before the
                        matching |:finally| (if present), the commands
                        following the ":finally" up to the matching |:endtry|
                        are executed first.  This process applies to all
                        nested ":try"s inside the function.  The function
                        returns at the outermost ":endtry".


                                                *function-argument* *a:var*
An argument can be defined by giving its name.  In the function this can then
be used as "a:name" ("a:" for argument).

                                                *a:0* *a:1* *a:000* *E740*
Up to 20 arguments can be given, separated by commas.  After the named
arguments an argument "..." can be specified, which means that more arguments
may optionally be following.  In the function the extra arguments can be used
as "a:1", "a:2", etc.  "a:0" is set to the number of extra arguments (which
can be 0).  "a:000" is set to a |List| that contains these arguments.  Note
that "a:1" is the same as "a:000[0]".

                                                                *E742*
The a: scope and the variables in it cannot be changed, they are fixed.
However, if a |List| or |Dictionary| is used, you can changes their contents.
Thus you can pass a |List| to a function and have the function add an item to
it.  If you want to make sure the function cannot change a |List| or
|Dictionary| use |:lockvar|.

When not using "...", the number of arguments in a function call must be equal
to the number of named arguments.  When using "...", the number of arguments
may be larger.

It is also possible to define a function without any arguments.  You must
still supply the () then.  The body of the function follows in the next lines,
until the matching |:endfunction|.  It is allowed to define another function
inside a function body.


                                                        *local-variables*
Inside a function variables can be used.  These are local variables, which
will disappear when the function returns.  Global variables need to be
accessed with "g:".

Example:
  :function Table(title, ...)
  :  echohl Title
  :  echo a:title
  :  echohl None
  :  echo a:0 . " items:"
  :  for s in a:000
  :    echon ' ' . s
  :  endfor
  :endfunction

This function can then be called with:
  call Table("Table", "line1", "line2")
  call Table("Empty Table")

To return more than one value, pass the name of a global variable:
  :function Compute(n1, n2, divname)
  :  if a:n2 == 0
  :    return "fail"
  :  endif
  :  let g:{a:divname} = a:n1 / a:n2
  :  return "ok"
  :endfunction

This function can then be called with:
  :let success = Compute(13, 1324, "div")
  :if success == "ok"
  :  echo div
  :endif

An alternative is to return a command that can be executed.  This also works
with local variables in a calling function.  Example:
  :function Foo()
  :  execute Bar()
  :  echo "line " . lnum . " column " . col
  :endfunction

  :function Bar()
  :  return "let lnum = " . line(".") . " | let col = " . col(".")
  :endfunction

The names "lnum" and "col" could also be passed as argument to Bar(), to allow
the caller to set the names.


                                                *:cal* *:call* *E107* *E117*
:[range]cal[l] {name}([arguments])
                Call a function.  The name of the function and its arguments
                are as specified with |:function|.  Up to 20 arguments can be
                used.
                Without a range and for functions that accept a range, the
                function is called once.  When a range is given the cursor is
                positioned at the start of the first line before executing the
                function.
                When a range is given and the function doesn't handle it
                itself, the function is executed for each line in the range,
                with the cursor in the first column of that line.  The cursor
                is left at the last line (possibly moved by the last function
                call).  The arguments are re-evaluated for each line.  Thus
                this works:

                                                *function-range-example* 
     :function Mynumber(arg)
     :  echo line(".") . " " . a:arg
     :endfunction
     :1,5call Mynumber(getline("."))
 
                The "a:firstline" and "a:lastline" are defined anyway, they
                can be used to do something different at the start or end of
                the range.

                Example of a function that handles the range itself:

     :function Cont() range
     :  execute (a:firstline + 1) . "," . a:lastline . 's/^/\t\\ '
     :endfunction
     :4,8call Cont()
 
                This function inserts the continuation character "\" in front
                of all the lines in the range, except the first one.


                                                                *E132*
The recursiveness of user functions is restricted with the |'maxfuncdepth'|
option.


AUTOMATICALLY LOADING FUNCTIONS 

                                                        *autoload-functions*
When using many or large functions, it's possible to automatically define them
only when they are used.  There are two methods: with an autocommand and with
the "autoload" directory in 'runtimepath'.


Using an autocommand 

This is introduced in the user manual, section |41.14|.

The autocommand is useful if you have a plugin that is a long Vim script file.
You can define the autocommand and quickly quit the script with |:finish|.
That makes Vim startup faster.  The autocommand should then load the same file
again, setting a variable to skip the |:finish| command.

Use the FuncUndefined autocommand event with a pattern that matches the
function(s) to be defined.  Example:

     :au FuncUndefined BufNet* source ~/vim/bufnetfuncs.vim

The file "~/vim/bufnetfuncs.vim" should then define functions that start with
"BufNet".  Also see |FuncUndefined|.


Using an autoload script 

                                                        *autoload* *E746*
This is introduced in the user manual, section |41.15|.

Using a script in the "autoload" directory is simpler, but requires using
exactly the right file name.  A function that can be autoloaded has a name
like this:

     :call filename#funcname()

When such a function is called, and it is not defined yet, Vim will search the
"autoload" directories in 'runtimepath' for a script file called
"filename.vim".  For example "~/.vim/autoload/filename.vim".  That file should
then define the function like this:

     function filename#funcname()
        echo "Done!"
     endfunction

The file name and the name used before the # in the function must match
exactly, and the defined function must have the name exactly as it will be
called.

It is possible to use subdirectories.  Every # in the function name works like
a path separator.  Thus when calling a function:

     :call foo#bar#func()

Vim will look for the file "autoload/foo/bar.vim" in 'runtimepath'.

This also works when reading a variable that has not been set yet:

     :let l = foo#bar#lvar

However, when the autoload script was already loaded it won't be loaded again
for an unknown variable.

When assigning a value to such a variable nothing special happens.  This can
be used to pass settings to the autoload script before it's loaded:

     :let foo#bar#toggle = 1
     :call foo#bar#func()

Note that when you make a mistake and call a function that is supposed to be
defined in an autoload script, but the script doesn't actually define the
function, the script will be sourced every time you try to call the function.
And you will get an error message every time.

Also note that if you have two script files, and one calls a function in the
other and vise versa, before the used function is defined, it won't work.
Avoid using the autoload functionality at the toplevel.

Hint: If you distribute a bunch of scripts you can pack them together with the
|vimball| utility.  Also read the user manual |distribute-script|.

==============================================================================

6. Curly braces names                                   *curly-braces-names*

Wherever you can use a variable, you can use a "curly braces name" variable.
This is a regular variable name with one or more expressions wrapped in braces
{} like this:
     my_{adjective}_variable

When Vim encounters this, it evaluates the expression inside the braces, puts
that in place of the expression, and re-interprets the whole as a variable
name.  So in the above example, if the variable "adjective" was set to
"noisy", then the reference would be to "my_noisy_variable", whereas if
"adjective" was set to "quiet", then it would be to "my_quiet_variable".

One application for this is to create a set of variables governed by an option
value.  For example, the statement
     echo my_{&background}_message

would output the contents of "my_dark_message" or "my_light_message" depending
on the current value of 'background'.

You can use multiple brace pairs:
     echo my_{adverb}_{adjective}_message
..or even nest them:
     echo my_{ad{end_of_word}}_message
where "end_of_word" is either "verb" or "jective".

However, the expression inside the braces must evaluate to a valid single
variable name, e.g. this is invalid:
     :let foo='a + b'
     :echo c{foo}d
.. since the result of expansion is "ca + bd", which is not a variable name.


                                                *curly-braces-function-names*
You can call and define functions by an evaluated name in a similar way.
Example:
     :let func_end='whizz'
     :call my_func_{func_end}(parameter)

This would call the function "my_func_whizz(parameter)".

==============================================================================

7. Commands                                             *expression-commands*


:let {var-name} = {expr1}                           *:let* *E18*
                        Set internal variable {var-name} to the result of the
                        expression {expr1}.  The variable will get the type
                        from the {expr}.  If {var-name} didn't exist yet, it
                        is created.


:let {var-name}[{idx}] = {expr1}                    *E689*
                        Set a list item to the result of the expression
                        {expr1}.  {var-name} must refer to a list and {idx}
                        must be a valid index in that list.  For nested list
                        the index can be repeated.
                        This cannot be used to add an item to a list.


                                                        *E711* *E719*

:let {var-name}[{idx1}:{idx2}] = {expr1}            *E708* *E709* *E710*
                        Set a sequence of items in a |List| to the result of
                        the expression {expr1}, which must be a list with the
                        correct number of items.
                        {idx1} can be omitted, zero is used instead.
                        {idx2} can be omitted, meaning the end of the list.
                        When the selected range of items is partly past the
                        end of the list, items will be added.


                                        *:let+=* *:let-=* *:let.=* *E734*
:let {var} += {expr1}       Like ":let {var} = {var} + {expr1}".
:let {var} -= {expr1}       Like ":let {var} = {var} - {expr1}".
:let {var} .= {expr1}       Like ":let {var} = {var} . {expr1}".
                        These fail if {var} was not set yet and when the type
                        of {var} and {expr1} don't fit the operator.



:let ${env-name} = {expr1}                  *:let-environment* *:let-$*
                        Set environment variable {env-name} to the result of
                        the expression {expr1}.  The type is always String.
:let ${env-name} .= {expr1}
                        Append {expr1} to the environment variable {env-name}.
                        If the environment variable didn't exist yet this
                        works like "=".


:let @{reg-name} = {expr1}                  *:let-register* *:let-@*
                        Write the result of the expression {expr1} in register
                        {reg-name}.  {reg-name} must be a single letter, and
                        must be the name of a writable register (see
                        |registers|).  "@@" can be used for the unnamed
                        register, "@/" for the search pattern.
                        If the result of {expr1} ends in a <CR> or <NL>, the
                        register will be linewise, otherwise it will be set to
                        characterwise.
                        This can be used to clear the last search pattern:
                             :let @/ = ""
                        This is different from searching for an empty string,
                        that would match everywhere.

:let @{reg-name} .= {expr1}
                        Append {expr1} to register {reg-name}.  If the
                        register was empty it's like setting it to {expr1}.


:let &{option-name} = {expr1}                   *:let-option* *:let-star*
                        Set option {option-name} to the result of the
                        expression {expr1}.  A String or Number value is
                        always converted to the type of the option.
                        For an option local to a window or buffer the effect
                        is just like using the |:set| command: both the local
                        value and the global value are changed.
                        Example:
                             :let &path = &path . ',/usr/local/include'

:let &{option-name} .= {expr1}
                        For a string option: Append {expr1} to the value.
                        Does not insert a comma like |:set+=|.

:let &{option-name} += {expr1}
:let &{option-name} -= {expr1}
                        For a number or boolean option: Add or subtract
                        {expr1}.

:let &l:{option-name} = {expr1}
:let &l:{option-name} .= {expr1}
:let &l:{option-name} += {expr1}
:let &l:{option-name} -= {expr1}
                        Like above, but only set the local value of an option
                        (if there is one).  Works like |:setlocal|.

:let &g:{option-name} = {expr1}
:let &g:{option-name} .= {expr1}
:let &g:{option-name} += {expr1}
:let &g:{option-name} -= {expr1}
                        Like above, but only set the global value of an option
                        (if there is one).  Works like |:setglobal|.


:let [{name1}, {name2}, ...] = {expr1}              *:let-unpack* *E687* *E688*
                        {expr1} must evaluate to a |List|.  The first item in
                        the list is assigned to {name1}, the second item to
                        {name2}, etc.
                        The number of names must match the number of items in
                        the |List|.
                        Each name can be one of the items of the ":let"
                        command as mentioned above.
                        Example:
                             :let [s, item] = GetItem(s)
                        Detail: {expr1} is evaluated first, then the
                        assignments are done in sequence.  This matters if
                        {name2} depends on {name1}.  Example:
                             :let x = [0, 1]
                             :let i = 0
                             :let [i, x[i]] = [1, 2]
                             :echo x
                        The result is [0, 2].

:let [{name1}, {name2}, ...] .= {expr1}
:let [{name1}, {name2}, ...] += {expr1}
:let [{name1}, {name2}, ...] -= {expr1}
                        Like above, but append/add/subtract the value for each
                        |List| item.

:let [{name}, ..., ; {lastname}] = {expr1}
                        Like |:let-unpack| above, but the |List| may have more
                        items than there are names.  A list of the remaining
                        items is assigned to {lastname}.  If there are no
                        remaining items {lastname} is set to an empty list.
                        Example:
                             :let [a, b; rest] = ["aval", "bval", 3, 4]
 
:let [{name}, ..., ; {lastname}] .= {expr1}
:let [{name}, ..., ; {lastname}] += {expr1}
:let [{name}, ..., ; {lastname}] -= {expr1}
                        Like above, but append/add/subtract the value for each
                        |List| item.

                                                        *E106*
:let {var-name}     ..      List the value of variable {var-name}.  Multiple
                        variable names may be given.  Special names recognized

                        here:                           *E738*
                          g: global variables
                          b:        local buffer variables
                          w:        local window variables
                          t:    local tab page variables
                          s:        script-local variables
                          l:        local function variables
                          v:        Vim variables.

:let                        List the values of all variables.  The type of the
                        variable is indicated before the value:
                            <nothing>     String
                                #       Number
                                *   Funcref



:unl[et][!] {name} ...                                  *:unlet* *:unl* *E108*
                        Remove the internal variable {name}.  Several variable
                        names can be given, they are all removed.  The name
                        may also be a |List| or |Dictionary| item.
                        With [!] no error message is given for non-existing
                        variables.
                        One or more items from a |List| can be removed:
                             :unlet list[3]    " remove fourth item
                             :unlet list[3:]   " remove fourth item to last
                        One item from a |Dictionary| can be removed at a time:
                             :unlet dict['two']
                             :unlet dict.two


:lockv[ar][!] [depth] {name} ...                        *:lockvar* *:lockv*
                        Lock the internal variable {name}.  Locking means that
                        it can no longer be changed (until it is unlocked).
                        A locked variable can be deleted:
                             :lockvar v
                             :let v = 'asdf'         " fails!
                             :unlet v

                                                        *E741*
                        If you try to change a locked variable you get an
                        error message: "E741: Value of {name} is locked"

                        [depth] is relevant when locking a |List| or
                        |Dictionary|.  It specifies how deep the locking goes:
                                1       Lock the |List| or |Dictionary| itself,
                                        cannot add or remove items, but can
                                        still change their values.
                                2       Also lock the values, cannot change
                                        the items.  If an item is a |List| or
                                        |Dictionary|, cannot add or remove
                                        items, but can still change the
                                        values.
                                3       Like 2 but for the |List| /
                                        |Dictionary| in the |List| /
                                        |Dictionary|, one level deeper.
                        The default [depth] is 2, thus when {name} is a |List|
                        or |Dictionary| the values cannot be changed.

                                                                *E743*
                        For unlimited depth use [!] and omit [depth].
                        However, there is a maximum depth of 100 to catch
                        loops.

                        Note that when two variables refer to the same |List|
                        and you lock one of them, the |List| will also be
                        locked when used through the other variable.
                        Example:
                             :let l = [0, 1, 2, 3]
                             :let cl = l
                             :lockvar l
                             :let cl[1] = 99         " won't work!
                        You may want to make a copy of a list to avoid this.
                        See |deepcopy()|.



:unlo[ckvar][!] [depth] {name} ...                      *:unlockvar* *:unlo*
                        Unlock the internal variable {name}.  Does the
                        opposite of |:lockvar|.



:if {expr1}                  *:if* *:endif* *:en* *E171* *E579* *E580*
:en[dif]                Execute the commands until the next matching ":else"
                        or ":endif" if {expr1} evaluates to non-zero.

                        From Vim version 4.5 until 5.0, every Ex command in
                        between the ":if" and ":endif" is ignored.  These two
                        commands were just to allow for future expansions in a
                        backwards compatible way.  Nesting was allowed.  Note
                        that any ":else" or ":elseif" was ignored, the "else"
                        part was not executed either.

                        You can use this to remain compatible with older
                        versions:
                             :if version >= 500
                             :  version-5-specific-commands
                             :endif
                        The commands still need to be parsed to find the
                        "endif".  Sometimes an older Vim has a problem with a
                        new command.  For example, ":silent" is recognized as
                        a ":substitute" command.  In that case ":execute" can
                        avoid problems:
                             :if version >= 600
                             :  execute "silent 1,$delete"
                             :endif
 
                        NOTE: The ":append" and ":insert" commands don't work
                        properly in between ":if" and ":endif".


                                                *:else* *:el* *E581* *E583*
:el[se]                 Execute the commands until the next matching ":else"
                        or ":endif" if they previously were not being
                        executed.


                                        *:elseif* *:elsei* *E582* *E584*
:elsei[f] {expr1}       Short for ":else" ":if", with the addition that there
                        is no extra ":endif".


:wh[ile] {expr1}                        *:while* *:endwhile* *:wh* *:endw*

                                                *E170* *E585* *E588* *E733*
:endw[hile]             Repeat the commands between ":while" and ":endwhile",
                        as long as {expr1} evaluates to non-zero.
                        When an error is detected from a command inside the
                        loop, execution continues after the "endwhile".
                        Example:
                             :let lnum = 1
                             :while lnum <= line("$")
                                :call FixLine(lnum)
                                :let lnum = lnum + 1
                             :endwhile
 
                        NOTE: The ":append" and ":insert" commands don't work
                        properly inside a ":while" and ":for" loop.


:for {var} in {list}                                        *:for* *E690* *E732*

:endfo[r]                                               *:endfo* *:endfor*
                        Repeat the commands between ":for" and ":endfor" for
                        each item in {list}.  Variable {var} is set to the
                        value of each item.
                        When an error is detected for a command inside the
                        loop, execution continues after the "endfor".
                        Changing {list} inside the loop affects what items are
                        used.  Make a copy if this is unwanted:
                             :for item in copy(mylist)
                        When not making a copy, Vim stores a reference to the
                        next item in the list, before executing the commands
                        with the current item.  Thus the current item can be
                        removed without effect.  Removing any later item means
                        it will not be found.  Thus the following example
                        works (an inefficient way to make a list empty):
                             :for item in mylist
                                :call remove(mylist, 0)
                             :endfor
                        Note that reordering the list (e.g., with sort() or
                        reverse()) may have unexpected effects.
                        Note that the type of each list item should be
                        identical to avoid errors for the type of {var}
                        changing.  Unlet the variable at the end of the loop
                        to allow multiple item types.

:for [{var1}, {var2}, ...] in {listlist}
:endfo[r]
                        Like ":for" above, but each item in {listlist} must be
                        a list, of which each item is assigned to {var1},
                        {var2}, etc.  Example:
                             :for [lnum, col] in [[1, 3], [2, 5], [3, 8]]
                                :echo getline(lnum)[col]
                             :endfor
 

                                                *:continue* *:con* *E586*
:con[tinue]             When used inside a ":while" or ":for" loop, jumps back
                        to the start of the loop.
                        If it is used after a |:try| inside the loop but
                        before the matching |:finally| (if present), the
                        commands following the ":finally" up to the matching
                        |:endtry| are executed first.  This process applies to
                        all nested ":try"s inside the loop.  The outermost
                        ":endtry" then jumps back to the start of the loop.


                                                *:break* *:brea* *E587*
:brea[k]                When used inside a ":while" or ":for" loop, skips to
                        the command after the matching ":endwhile" or
                        ":endfor".
                        If it is used after a |:try| inside the loop but
                        before the matching |:finally| (if present), the
                        commands following the ":finally" up to the matching
                        |:endtry| are executed first.  This process applies to
                        all nested ":try"s inside the loop.  The outermost
                        ":endtry" then jumps to the command after the loop.


:try                                *:try* *:endt* *:endtry* *E600* *E601* *E602*
:endt[ry]               Change the error handling for the commands between
                        ":try" and ":endtry" including everything being
                        executed across ":source" commands, function calls,
                        or autocommand invocations.

                        When an error or interrupt is detected and there is
                        a |:finally| command following, execution continues
                        after the ":finally".  Otherwise, or when the
                        ":endtry" is reached thereafter, the next
                        (dynamically) surrounding ":try" is checked for
                        a corresponding ":finally" etc.  Then the script
                        processing is terminated.  (Whether a function
                        definition has an "abort" argument does not matter.)
                        Example:
             :try | edit too much | finally | echo "cleanup" | endtry
             :echo "impossible"      " not reached, script terminated above
 
                        Moreover, an error or interrupt (dynamically) inside
                        ":try" and ":endtry" is converted to an exception.  It
                        can be caught as if it were thrown by a |:throw|
                        command (see |:catch|).  In this case, the script
                        processing is not terminated.

                        The value "Vim:Interrupt" is used for an interrupt
                        exception.  An error in a Vim command is converted
                        to a value of the form "Vim({command}):{errmsg}",
                        other errors are converted to a value of the form
                        "Vim:{errmsg}".  {command} is the full command name,
                        and {errmsg} is the message that is displayed if the
                        error exception is not caught, always beginning with
                        the error number.
                        Examples:
             :try | sleep 100 | catch /^Vim:Interrupt$/ | endtry
             :try | edit | catch /^Vim(edit):E\d\+/ | echo "error" | endtry
 

                                        *:cat* *:catch* *E603* *E604* *E605*
:cat[ch] /{pattern}/    The following commands until the next ":catch",
                        |:finally|, or |:endtry| that belongs to the same
                        |:try| as the ":catch" are executed when an exception
                        matching {pattern} is being thrown and has not yet
                        been caught by a previous ":catch".  Otherwise, these
                        commands are skipped.
                        When {pattern} is omitted all errors are caught.
                        Examples:
             :catch /^Vim:Interrupt$/        " catch interrupts (CTRL-C)
             :catch /^Vim\%((\a\+)\)\=:E/    " catch all Vim errors
             :catch /^Vim\%((\a\+)\)\=:/     " catch errors and interrupts
             :catch /^Vim(write):/           " catch all errors in :write
             :catch /^Vim\%((\a\+)\)\=:E123/ " catch error E123
             :catch /my-exception/           " catch user exception
             :catch /.*/                     " catch everything
             :catch                          " same as /.*/
 
                        Another character can be used instead of / around the
                        {pattern}, so long as it does not have a special
                        meaning (e.g., '|' or '"'') and doesn't occur inside
                        {pattern}.
                        NOTE: It is not reliable to ":catch" the TEXT of
                        an error message because it may vary in different
                        locales.


                                        *:fina* *:finally* *E606* *E607*
:fina[lly]              The following commands until the matching |:endtry|
                        are executed whenever the part between the matching
                        |:try| and the ":finally" is left:  either by falling
                        through to the ":finally" or by a |:continue|,
                        |:break|, |:finish|, or |:return|, or by an error or
                        interrupt or exception (see |:throw|).


                                                        *:th* *:throw* *E608*
:th[row] {expr1}        The {expr1} is evaluated and thrown as an exception.
                        If the ":throw" is used after a |:try| but before the
                        first corresponding |:catch|, commands are skipped
                        until the first ":catch" matching {expr1} is reached.
                        If there is no such ":catch" or if the ":throw" is
                        used after a ":catch" but before the |:finally|, the
                        commands following the ":finally" (if present) up to
                        the matching |:endtry| are executed.  If the ":throw"
                        is after the ":finally", commands up to the ":endtry"
                        are skipped.  At the ":endtry", this process applies
                        again for the next dynamically surrounding ":try"
                        (which may be found in a calling function or sourcing
                        script), until a matching ":catch" has been found.
                        If the exception is not caught, the command processing
                        is terminated.
                        Example:
             :try | throw "oops" | catch /^oo/ | echo "caught" | endtry
 


                                                        *:ec* *:echo*
:ec[ho] {expr1} ..      Echoes each {expr1}, with a space in between.  The
                        first {expr1} starts on a new line.
                        Also see |:comment|.
                        Use "\n" to start a new line.  Use "\r" to move the
                        cursor to the first column.
                        Uses the highlighting set by the |:echohl| command.
                        Cannot be followed by a comment.
                        Example:
             :echo "the value of 'shell' is" &shell
                        A later redraw may make the message disappear again.
                        To avoid that a command from before the ":echo" causes
                        a redraw afterwards (redraws are often postponed until
                        you type something), force a redraw with the |:redraw|
                        command.  Example:
             :new | redraw | echo "there is a new window"
 

                                                        *:echon*
:echon {expr1} .. Echoes each {expr1}, without anything added.  Also see
                        |:comment|.
                        Uses the highlighting set by the |:echohl| command.
                        Cannot be followed by a comment.
                        Example:
                             :echon "the value of 'shell' is " &shell
 
                        Note the difference between using ":echo", which is a
                        Vim command, and ":!echo", which is an external shell
                        command:
             :!echo %                --> filename
                        The arguments of ":!" are expanded, see |:_%|.
             :!echo "%"              --> filename or "filename"
                        Like the previous example.  Whether you see the double
                        quotes or not depends on your 'shell'.
             :echo %                 --> nothing
                        The '%' is an illegal character in an expression.
             :echo "%"               --> %
                        This just echoes the '%' character.
             :echo expand("%")       --> filename
                        This calls the expand() function to expand the '%'.


                                                        *:echoh* *:echohl*
:echoh[l] {name}        Use the highlight group {name} for the following
                        |:echo|, |:echon| and |:echomsg| commands.  Also used
                        for the |input()| prompt.  Example:
             :echohl WarningMsg | echo "Don't panic!" | echohl None
                        Don't forget to set the group back to "None",
                        otherwise all following echo's will be highlighted.


                                                        *:echom* *:echomsg*
:echom[sg] {expr1} ..   Echo the expression(s) as a true message, saving the
                        message in the |message-history|.
                        Spaces are placed between the arguments as with the
                        |:echo| command.  But unprintable characters are
                        displayed, not interpreted.
                        Uses the highlighting set by the |:echohl| command.
                        Example:
             :echomsg "It's a Zizzer Zazzer Zuzz, as you can plainly see."
 

                                                        *:echoe* *:echoerr*
:echoe[rr] {expr1} ..   Echo the expression(s) as an error message, saving the
                        message in the |message-history|.  When used in a
                        script or function the line number will be added.
                        Spaces are placed between the arguments as with the
                        :echo command.  When used inside a try conditional,
                        the message is raised as an error exception instead
                        (see |try-echoerr|).
                        Example:
             :echoerr "This script just failed!"
                        If you just want a highlighted message use |:echohl|.
                        And to get a beep:
             :exe "normal \<Esc>"
 

                                                        *:exe* *:execute*
:exe[cute] {expr1} ..   Executes the string that results from the evaluation
                        of {expr1} as an Ex command.  Multiple arguments are
                        concatenated, with a space in between.  {expr1} is
                        used as the processed command, command line editing
                        keys are not recognized.
                        Cannot be followed by a comment.
                        Examples:
             :execute "buffer " nextbuf
             :execute "normal " count . "w"
 
                        ":execute" can be used to append a command to commands
                        that don't accept a '|'.  Example:
             :execute '!ls' | echo "theend"

                        ":execute" is also a nice way to avoid having to type
                        control characters in a Vim script for a ":normal"
                        command:
             :execute "normal ixxx\<Esc>"
                        This has an <Esc> character, see |expr-string|.

                        Note: The executed string may be any command-line, but
                        you cannot start or end a "while", "for" or "if"
                        command.  Thus this is illegal:
             :execute 'while i > 5'
             :execute 'echo "test" | break'
 
                        It is allowed to have a "while" or "if" command
                        completely in the executed string:
             :execute 'while i < 5 | echo i | let i = i + 1 | endwhile'
 


                                                        *:comment*
                        ":execute", ":echo" and ":echon" cannot be followed by
                        a comment directly, because they see the '"'' as the
                        start of a string.  But, you can use '|' followed by a
                        comment.  Example:
             :echo "foo" | "this is a comment

==============================================================================

8. Exception handling                                   *exception-handling*

The Vim script language comprises an exception handling feature.  This section
explains how it can be used in a Vim script.

Exceptions may be raised by Vim on an error or on interrupt, see
|catch-errors| and |catch-interrupt|.  You can also explicitly throw an
exception by using the ":throw" command, see |throw-catch|.



TRY CONDITIONALS                                        *try-conditionals*

Exceptions can be caught or can cause cleanup code to be executed.  You can
use a try conditional to specify catch clauses (that catch exceptions) and/or
a finally clause (to be executed for cleanup).
   A try conditional begins with a |:try| command and ends at the matching
|:endtry| command.  In between, you can use a |:catch| command to start
a catch clause, or a |:finally| command to start a finally clause.  There may
be none or multiple catch clauses, but there is at most one finally clause,
which must not be followed by any catch clauses.  The lines before the catch
clauses and the finally clause is called a try block.

     :try
     :  ...
     :  ...                          TRY BLOCK
     :  ...
     :catch /{pattern}/
     :  ...
     :  ...                          CATCH CLAUSE
     :  ...
     :catch /{pattern}/
     :  ...
     :  ...                          CATCH CLAUSE
     :  ...
     :finally
     :  ...
     :  ...                          FINALLY CLAUSE
     :  ...
     :endtry

The try conditional allows to watch code for exceptions and to take the
appropriate actions.  Exceptions from the try block may be caught.  Exceptions
from the try block and also the catch clauses may cause cleanup actions.
   When no exception is thrown during execution of the try block, the control
is transferred to the finally clause, if present.  After its execution, the
script continues with the line following the ":endtry".
   When an exception occurs during execution of the try block, the remaining
lines in the try block are skipped.  The exception is matched against the
patterns specified as arguments to the ":catch" commands.  The catch clause
after the first matching ":catch" is taken, other catch clauses are not
executed.  The catch clause ends when the next ":catch", ":finally", or
":endtry" command is reached - whatever is first.  Then, the finally clause
(if present) is executed.  When the ":endtry" is reached, the script execution
continues in the following line as usual.
   When an exception that does not match any of the patterns specified by the
":catch" commands is thrown in the try block, the exception is not caught by
that try conditional and none of the catch clauses is executed.  Only the
finally clause, if present, is taken.  The exception pends during execution of
the finally clause.  It is resumed at the ":endtry", so that commands after
the ":endtry" are not executed and the exception might be caught elsewhere,
see |try-nesting|.
   When during execution of a catch clause another exception is thrown, the
remaining lines in that catch clause are not executed.  The new exception is
not matched against the patterns in any of the ":catch" commands of the same
try conditional and none of its catch clauses is taken.  If there is, however,
a finally clause, it is executed, and the exception pends during its
execution.  The commands following the ":endtry" are not executed.  The new
exception might, however, be caught elsewhere, see |try-nesting|.
   When during execution of the finally clause (if present) an exception is
thrown, the remaining lines in the finally clause are skipped.  If the finally
clause has been taken because of an exception from the try block or one of the
catch clauses, the original (pending) exception is discarded.  The commands
following the ":endtry" are not executed, and the exception from the finally
clause is propagated and can be caught elsewhere, see |try-nesting|.

The finally clause is also executed, when a ":break" or ":continue" for
a ":while" loop enclosing the complete try conditional is executed from the
try block or a catch clause.  Or when a ":return" or ":finish" is executed
from the try block or a catch clause of a try conditional in a function or
sourced script, respectively.  The ":break", ":continue", ":return", or
":finish" pends during execution of the finally clause and is resumed when the
":endtry" is reached.  It is, however, discarded when an exception is thrown
from the finally clause.
   When a ":break" or ":continue" for a ":while" loop enclosing the complete
try conditional or when a ":return" or ":finish" is encountered in the finally
clause, the rest of the finally clause is skipped, and the ":break",
":continue", ":return" or ":finish" is executed as usual.  If the finally
clause has been taken because of an exception or an earlier ":break",
":continue", ":return", or ":finish" from the try block or a catch clause,
this pending exception or command is discarded.

For examples see |throw-catch| and |try-finally|.



NESTING OF TRY CONDITIONALS                             *try-nesting*

Try conditionals can be nested arbitrarily.  That is, a complete try
conditional can be put into the try block, a catch clause, or the finally
clause of another try conditional.  If the inner try conditional does not
catch an exception thrown in its try block or throws a new exception from one
of its catch clauses or its finally clause, the outer try conditional is
checked according to the rules above.  If the inner try conditional is in the
try block of the outer try conditional, its catch clauses are checked, but
otherwise only the finally clause is executed.  It does not matter for
nesting, whether the inner try conditional is directly contained in the outer
one, or whether the outer one sources a script or calls a function containing
the inner try conditional.

When none of the active try conditionals catches an exception, just their
finally clauses are executed.  Thereafter, the script processing terminates.
An error message is displayed in case of an uncaught exception explicitly
thrown by a ":throw" command.  For uncaught error and interrupt exceptions
implicitly raised by Vim, the error message(s) or interrupt message are shown
as usual.

For examples see |throw-catch|.



EXAMINING EXCEPTION HANDLING CODE                       *except-examine*

Exception handling code can get tricky.  If you are in doubt what happens, set
'verbose' to 13 or use the ":13verbose" command modifier when sourcing your
script file.  Then you see when an exception is thrown, discarded, caught, or
finished.  When using a verbosity level of at least 14, things pending in
a finally clause are also shown.  This information is also given in debug mode
(see |debug-scripts|).



THROWING AND CATCHING EXCEPTIONS                        *throw-catch*

You can throw any number or string as an exception.  Use the |:throw| command
and pass the value to be thrown as argument:
     :throw 4711
     :throw "string"

                                                        *throw-expression*
You can also specify an expression argument.  The expression is then evaluated
first, and the result is thrown:
     :throw 4705 + strlen("string")
     :throw strpart("strings", 0, 6)

An exception might be thrown during evaluation of the argument of the ":throw"
command.  Unless it is caught there, the expression evaluation is abandoned.
The ":throw" command then does not throw a new exception.
   Example:

     :function! Foo(arg)
     :  try
     :    throw a:arg
     :  catch /foo/
     :  endtry
     :  return 1
     :endfunction
     :
     :function! Bar()
     :  echo "in Bar"
     :  return 4710
     :endfunction
     :
     :throw Foo("arrgh") + Bar()

This throws "arrgh", and "in Bar" is not displayed since Bar() is not
executed.
     :throw Foo("foo") + Bar()
however displays "in Bar" and throws 4711.

Any other command that takes an expression as argument might also be
abandoned by an (uncaught) exception during the expression evaluation.  The
exception is then propagated to the caller of the command.
   Example:

     :if Foo("arrgh")
     :  echo "then"
     :else
     :  echo "else"
     :endif

Here neither of "then" or "else" is displayed.


                                                        *catch-order*
Exceptions can be caught by a try conditional with one or more |:catch|
commands, see |try-conditionals|.   The values to be caught by each ":catch"
command can be specified as a pattern argument.  The subsequent catch clause
gets executed when a matching exception is caught.
   Example:

     :function! Foo(value)
     :  try
     :    throw a:value
     :  catch /^\d\+$/
     :    echo "Number thrown"
     :  catch /.*/
     :    echo "String thrown"
     :  endtry
     :endfunction
     :
     :call Foo(0x1267)
     :call Foo('string')

The first call to Foo() displays "Number thrown", the second "String thrown".
An exception is matched against the ":catch" commands in the order they are
specified.  Only the first match counts.  So you should place the more
specific ":catch" first.  The following order does not make sense:

     :  catch /.*/
     :    echo "String thrown"
     :  catch /^\d\+$/
     :    echo "Number thrown"

The first ":catch" here matches always, so that the second catch clause is
never taken.


                                                        *throw-variables*
If you catch an exception by a general pattern, you may access the exact value
in the variable YXXYv:exception|:

     :  catch /^\d\+$/
     :    echo "Number thrown.  Value is" v:exception

You may also be interested where an exception was thrown.  This is stored in
|v:throwpoint|.  Note that "v:exception" and "v:throwpoint" are valid for the
exception most recently caught as long it is not finished.
   Example:

     :function! Caught()
     :  if v:exception != ""
     :    echo 'Caught "' . v:exception . '" in ' . v:throwpoint
     :  else
     :    echo 'Nothing caught'
     :  endif
     :endfunction
     :
     :function! Foo()
     :  try
     :    try
     :      try
     :        throw 4711
     :      finally
     :        call Caught()
     :      endtry
     :    catch /.*/
     :      call Caught()
     :      throw "oops"
     :    endtry
     :  catch /.*/
     :    call Caught()
     :  finally
     :    call Caught()
     :  endtry
     :endfunction
     :
     :call Foo()

This displays

     Nothing caught
     Caught "4711" in function Foo, line 4
     Caught "oops" in function Foo, line 10
     Nothing caught

A practical example:  The following command ":LineNumber" displays the line
number in the script or function where it has been used:

     :function! LineNumber()
     :    return substitute(v:throwpoint, '.*\D\(\d\+\).*', '\1', "")
     :endfunction
     :command! LineNumber try | throw "" | catch | echo LineNumber() | endtry
 

                                                        *try-nested*
An exception that is not caught by a try conditional can be caught by
a surrounding try conditional:

     :try
     :  try
     :    throw "foo"
     :  catch /foobar/
     :    echo "foobar"
     :  finally
     :    echo "inner finally"
     :  endtry
     :catch /foo/
     :  echo "foo"
     :endtry

The inner try conditional does not catch the exception, just its finally
clause is executed.  The exception is then caught by the outer try
conditional.  The example displays "inner finally" and then "foo".


                                                        *throw-from-catch*
You can catch an exception and throw a new one to be caught elsewhere from the
catch clause:

     :function! Foo()
     :  throw "foo"
     :endfunction
     :
     :function! Bar()
     :  try
     :    call Foo()
     :  catch /foo/
     :    echo "Caught foo, throw bar"
     :    throw "bar"
     :  endtry
     :endfunction
     :
     :try
     :  call Bar()
     :catch /.*/
     :  echo "Caught" v:exception
     :endtry

This displays "Caught foo, throw bar" and then "Caught bar".


                                                        *rethrow*
There is no real rethrow in the Vim script language, but you may throw
"v:exception" instead:

     :function! Bar()
     :  try
     :    call Foo()
     :  catch /.*/
     :    echo "Rethrow" v:exception
     :    throw v:exception
     :  endtry
     :endfunction

                                                        *try-echoerr*
Note that this method cannot be used to "rethrow" Vim error or interrupt
exceptions, because it is not possible to fake Vim internal exceptions.
Trying so causes an error exception.  You should throw your own exception
denoting the situation.  If you want to cause a Vim error exception containing
the original error exception value, you can use the |:echoerr| command:

     :try
     :  try
     :    asdf
     :  catch /.*/
     :    echoerr v:exception
     :  endtry
     :catch /.*/
     :  echo v:exception
     :endtry

This code displays

        Vim(echoerr):Vim:E492: Not an editor command:   asdf 



CLEANUP CODE                                            *try-finally*

Scripts often change global settings and restore them at their end.  If the
user however interrupts the script by pressing CTRL-C, the settings remain in
an inconsistent state.  The same may happen to you in the development phase of
a script when an error occurs or you explicitly throw an exception without
catching it.  You can solve these problems by using a try conditional with
a finally clause for restoring the settings.  Its execution is guaranteed on
normal control flow, on error, on an explicit ":throw", and on interrupt.
(Note that errors and interrupts from inside the try conditional are converted
to exceptions.  When not caught, they terminate the script after the finally
clause has been executed.)
Example:

     :try
     :  let s:saved_ts = &ts
     :  set ts=17
     :
     :  " Do the hard work here.
     :
     :finally
     :  let &ts = s:saved_ts
     :  unlet s:saved_ts
     :endtry

This method should be used locally whenever a function or part of a script
changes global settings which need to be restored on failure or normal exit of
that function or script part.


                                                        *break-finally*
Cleanup code works also when the try block or a catch clause is left by
a ":continue", ":break", ":return", or ":finish".
   Example:

     :let first = 1
     :while 1
     :  try
     :    if first
     :      echo "first"
     :      let first = 0
     :      continue
     :    else
     :      throw "second"
     :    endif
     :  catch /.*/
     :    echo v:exception
     :    break
     :  finally
     :    echo "cleanup"
     :  endtry
     :  echo "still in while"
     :endwhile
     :echo "end"

This displays "first", "cleanup", "second", "cleanup", and "end".

     :function! Foo()
     :  try
     :    return 4711
     :  finally
     :    echo "cleanup\n"
     :  endtry
     :  echo "Foo still active"
     :endfunction
     :
     :echo Foo() "returned by Foo"

This displays "cleanup" and "4711 returned by Foo".  You don't need to add an
extra ":return" in the finally clause.  (Above all, this would override the
return value.)


                                                        *except-from-finally*
Using either of ":continue", ":break", ":return", ":finish", or ":throw" in
a finally clause is possible, but not recommended since it abandons the
cleanup actions for the try conditional.  But, of course, interrupt and error
exceptions might get raised from a finally clause.
   Example where an error in the finally clause stops an interrupt from
working correctly:

     :try
     :  try
     :    echo "Press CTRL-C for interrupt"
     :    while 1
     :    endwhile
     :  finally
     :    unlet novar
     :  endtry
     :catch /novar/
     :endtry
     :echo "Script still running"
     :sleep 1

If you need to put commands that could fail into a finally clause, you should
think about catching or ignoring the errors in these commands, see
|catch-errors| and |ignore-errors|.



CATCHING ERRORS                                         *catch-errors*

If you want to catch specific errors, you just have to put the code to be
watched in a try block and add a catch clause for the error message.  The
presence of the try conditional causes all errors to be converted to an
exception.  No message is displayed and |v:errmsg| is not set then.  To find
the right pattern for the ":catch" command, you have to know how the format of
the error exception is.
   Error exceptions have the following format:

     Vim({cmdname}):{errmsg}
or
     Vim:{errmsg}

{cmdname} is the name of the command that failed; the second form is used when
the command name is not known.  {errmsg} is the error message usually produced
when the error occurs outside try conditionals.  It always begins with
a capital "E", followed by a two or three-digit error number, a colon, and
a space.

Examples:

The command
     :unlet novar
normally produces the error message
     E108: No such variable: "novar"
which is converted inside try conditionals to an exception
     Vim(unlet):E108: No such variable: "novar"

The command
     :dwim
normally produces the error message
     E492: Not an editor command: dwim
which is converted inside try conditionals to an exception
     Vim:E492: Not an editor command: dwim

You can catch all ":unlet" errors by a
     :catch /^Vim(unlet):/
or all errors for misspelled command names by a
     :catch /^Vim:E492:/

Some error messages may be produced by different commands:
     :function nofunc
and
     :delfunction nofunc
both produce the error message
     E128: Function name must start with a capital: nofunc
which is converted inside try conditionals to an exception
     Vim(function):E128: Function name must start with a capital: nofunc
or
     Vim(delfunction):E128: Function name must start with a capital: nofunc
respectively.  You can catch the error by its number independently on the
command that caused it if you use the following pattern:
     :catch /^Vim(\a\+):E128:/

Some commands like
     :let x = novar
produce multiple error messages, here:
     E121: Undefined variable: novar
     E15: Invalid expression:  novar
Only the first is used for the exception value, since it is the most specific
one (see |except-several-errors|).  So you can catch it by
     :catch /^Vim(\a\+):E121:/

You can catch all errors related to the name "nofunc" by
     :catch /\<nofunc\>/

You can catch all Vim errors in the ":write" and ":read" commands by
     :catch /^Vim(\(write\|read\)):E\d\+:/

You can catch all Vim errors by the pattern
     :catch /^Vim\((\a\+)\)\=:E\d\+:/
 

                                                        *catch-text*
NOTE: You should never catch the error message text itself:
     :catch /No such variable/
only works in the english locale, but not when the user has selected
a different language by the |:language| command.  It is however helpful to
cite the message text in a comment:
     :catch /^Vim(\a\+):E108:/   " No such variable



IGNORING ERRORS                                         *ignore-errors*

You can ignore errors in a specific Vim command by catching them locally:

     :try
     :  write
     :catch
     :endtry

But you are strongly recommended NOT to use this simple form, since it could
catch more than you want.  With the ":write" command, some autocommands could
be executed and cause errors not related to writing, for instance:

     :au BufWritePre * unlet novar

There could even be such errors you are not responsible for as a script
writer: a user of your script might have defined such autocommands.  You would
then hide the error from the user.
   It is much better to use

     :try
     :  write
     :catch /^Vim(write):/
     :endtry

which only catches real write errors.  So catch only what you'd like to ignore
intentionally.

For a single command that does not cause execution of autocommands, you could
even suppress the conversion of errors to exceptions by the ":silent!"
command:
     :silent! nunmap k
This works also when a try conditional is active.



CATCHING INTERRUPTS                                     *catch-interrupt*

When there are active try conditionals, an interrupt (CTRL-C) is converted to
the exception "Vim:Interrupt".  You can catch it like every exception.  The
script is not terminated, then.
   Example:

     :function! TASK1()
     :  sleep 10
     :endfunction

     :function! TASK2()
     :  sleep 20
     :endfunction

     :while 1
     :  let command = input("Type a command: ")
     :  try
     :    if command == ""
     :      continue
     :    elseif command == "END"
     :      break
     :    elseif command == "TASK1"
     :      call TASK1()
     :    elseif command == "TASK2"
     :      call TASK2()
     :    else
     :      echo "\nIllegal command:" command
     :      continue
     :    endif
     :  catch /^Vim:Interrupt$/
     :    echo "\nCommand interrupted"
     :    " Caught the interrupt.  Continue with next prompt.
     :  endtry
     :endwhile

You can interrupt a task here by pressing CTRL-C; the script then asks for
a new command.  If you press CTRL-C at the prompt, the script is terminated.

For testing what happens when CTRL-C would be pressed on a specific line in
your script, use the debug mode and execute the |>quit| or |>interrupt|
command on that line.  See |debug-scripts|.



CATCHING ALL                                            *catch-all*

The commands

     :catch /.*/
     :catch //
     :catch

catch everything, error exceptions, interrupt exceptions and exceptions
explicitly thrown by the |:throw| command.  This is useful at the top level of
a script in order to catch unexpected things.
   Example:

     :try
     :
     :  " do the hard work here
     :
     :catch /MyException/
     :
     :  " handle known problem
     :
     :catch /^Vim:Interrupt$/
     :    echo "Script interrupted"
     :catch /.*/
     :  echo "Internal error (" . v:exception . ")"
     :  echo " - occurred at " . v:throwpoint
     :endtry
     :" end of script

Note: Catching all might catch more things than you want.  Thus, you are
strongly encouraged to catch only for problems that you can really handle by
specifying a pattern argument to the ":catch".
   Example: Catching all could make it nearly impossible to interrupt a script
by pressing CTRL-C:

     :while 1
     :  try
     :    sleep 1
     :  catch
     :  endtry
     :endwhile



EXCEPTIONS AND AUTOCOMMANDS                             *except-autocmd*

Exceptions may be used during execution of autocommands.  Example:

     :autocmd User x try
     :autocmd User x   throw "Oops!"
     :autocmd User x catch
     :autocmd User x   echo v:exception
     :autocmd User x endtry
     :autocmd User x throw "Arrgh!"
     :autocmd User x echo "Should not be displayed"
     :
     :try
     :  doautocmd User x
     :catch
     :  echo v:exception
     :endtry

This displays "Oops!" and "Arrgh!".


                                                        *except-autocmd-Pre*
For some commands, autocommands get executed before the main action of the
command takes place.  If an exception is thrown and not caught in the sequence
of autocommands, the sequence and the command that caused its execution are
abandoned and the exception is propagated to the caller of the command.
   Example:

     :autocmd BufWritePre * throw "FAIL"
     :autocmd BufWritePre * echo "Should not be displayed"
     :
     :try
     :  write
     :catch
     :  echo "Caught:" v:exception "from" v:throwpoint
     :endtry

Here, the ":write" command does not write the file currently being edited (as
you can see by checking 'modified'), since the exception from the BufWritePre
autocommand abandons the ":write".  The exception is then caught and the
script displays:

     Caught: FAIL from BufWrite Auto commands for "*"
 

                                                        *except-autocmd-Post*
For some commands, autocommands get executed after the main action of the
command has taken place.  If this main action fails and the command is inside
an active try conditional, the autocommands are skipped and an error exception
is thrown that can be caught by the caller of the command.
   Example:

     :autocmd BufWritePost * echo "File successfully written!"
     :
     :try
     :  write /i/m/p/o/s/s/i/b/l/e
     :catch
     :  echo v:exception
     :endtry

This just displays:

     Vim(write):E212: Can't open file for writing (/i/m/p/o/s/s/i/b/l/e)

If you really need to execute the autocommands even when the main action
fails, trigger the event from the catch clause.
   Example:

     :autocmd BufWritePre  * set noreadonly
     :autocmd BufWritePost * set readonly
     :
     :try
     :  write /i/m/p/o/s/s/i/b/l/e
     :catch
     :  doautocmd BufWritePost /i/m/p/o/s/s/i/b/l/e
     :endtry
 
You can also use ":silent!":

     :let x = "ok"
     :let v:errmsg = ""
     :autocmd BufWritePost * if v:errmsg != ""
     :autocmd BufWritePost *   let x = "after fail"
     :autocmd BufWritePost * endif
     :try
     :  silent! write /i/m/p/o/s/s/i/b/l/e
     :catch
     :endtry
     :echo x

This displays "after fail".

If the main action of the command does not fail, exceptions from the
autocommands will be catchable by the caller of the command: 

     :autocmd BufWritePost * throw ":-("
     :autocmd BufWritePost * echo "Should not be displayed"
     :
     :try
     :  write
     :catch
     :  echo v:exception
     :endtry
 

                                                        *except-autocmd-Cmd*
For some commands, the normal action can be replaced by a sequence of
autocommands.  Exceptions from that sequence will be catchable by the caller
of the command.
   Example:  For the ":write" command, the caller cannot know whether the file
had actually been written when the exception occurred.  You need to tell it in
some way.

     :if !exists("cnt")
     :  let cnt = 0
     :
     :  autocmd BufWriteCmd * if &modified
     :  autocmd BufWriteCmd *   let cnt = cnt + 1
     :  autocmd BufWriteCmd *   if cnt % 3 == 2
     :  autocmd BufWriteCmd *     throw "BufWriteCmdError"
     :  autocmd BufWriteCmd *   endif
     :  autocmd BufWriteCmd *   write | set nomodified
     :  autocmd BufWriteCmd *   if cnt % 3 == 0
     :  autocmd BufWriteCmd *     throw "BufWriteCmdError"
     :  autocmd BufWriteCmd *   endif
     :  autocmd BufWriteCmd *   echo "File successfully written!"
     :  autocmd BufWriteCmd * endif
     :endif
     :
     :try
     :       write
     :catch /^BufWriteCmdError$/
     :  if &modified
     :    echo "Error on writing (file contents not changed)"
     :  else
     :    echo "Error after writing"
     :  endif
     :catch /^Vim(write):/
     :    echo "Error on writing"
     :endtry

When this script is sourced several times after making changes, it displays
first
     File successfully written!
then
     Error on writing (file contents not changed)
then
     Error after writing
etc.


                                                        *except-autocmd-ill*
You cannot spread a try conditional over autocommands for different events.
The following code is ill-formed:

     :autocmd BufWritePre  * try
     :
     :autocmd BufWritePost * catch
     :autocmd BufWritePost *   echo v:exception
     :autocmd BufWritePost * endtry
     :
     :write



EXCEPTION HIERARCHIES AND PARAMETERIZED EXCEPTIONS      *except-hier-param*

Some programming languages allow to use hierarchies of exception classes or to
pass additional information with the object of an exception class.  You can do
similar things in Vim.
   In order to throw an exception from a hierarchy, just throw the complete
class name with the components separated by a colon, for instance throw the
string "EXCEPT:MATHERR:OVERFLOW" for an overflow in a mathematical library.
   When you want to pass additional information with your exception class, add
it in parentheses, for instance throw the string "EXCEPT:IO:WRITEERR(myfile)"
for an error when writing "myfile".
   With the appropriate patterns in the ":catch" command, you can catch for
base classes or derived classes of your hierarchy.  Additional information in
parentheses can be cut out from |v:exception| with the ":substitute" command.
   Example:

     :function! CheckRange(a, func)
     :  if a:a < 0
     :    throw "EXCEPT:MATHERR:RANGE(" . a:func . ")"
     :  endif
     :endfunction
     :
     :function! Add(a, b)
     :  call CheckRange(a:a, "Add")
     :  call CheckRange(a:b, "Add")
     :  let c = a:a + a:b
     :  if c < 0
     :    throw "EXCEPT:MATHERR:OVERFLOW"
     :  endif
     :  return c
     :endfunction
     :
     :function! Div(a, b)
     :  call CheckRange(a:a, "Div")
     :  call CheckRange(a:b, "Div")
     :  if (a:b == 0)
     :    throw "EXCEPT:MATHERR:ZERODIV"
     :  endif
     :  return a:a / a:b
     :endfunction
     :
     :function! Write(file)
     :  try
     :    execute "write" a:file
     :  catch /^Vim(write):/
     :    throw "EXCEPT:IO(" . getcwd() . ", " . a:file . "):WRITEERR"
     :  endtry
     :endfunction
     :
     :try
     :
     :  " something with arithmetics and I/O
     :
     :catch /^EXCEPT:MATHERR:RANGE/
     :  let function = substitute(v:exception, '.*(\(\a\+\)).*', '\1', "")
     :  echo "Range error in" function
     :
     :catch /^EXCEPT:MATHERR/        " catches OVERFLOW and ZERODIV
     :  echo "Math error"
     :
     :catch /^EXCEPT:IO/
     :  let dir = substitute(v:exception, '.*(\(.\+\),\s*.\+).*', '\1', "")
     :  let file = substitute(v:exception, '.*(.\+,\s*\(.\+\)).*', '\1', "")
     :  if file !~ '^/'
     :    let file = dir . "/" . file
     :  endif
     :  echo 'I/O error for "' . file . '"'
     :
     :catch /^EXCEPT/
     :  echo "Unspecified error"
     :
     :endtry

The exceptions raised by Vim itself (on error or when pressing CTRL-C) use
a flat hierarchy:  they are all in the "Vim" class.  You cannot throw yourself
exceptions with the "Vim" prefix; they are reserved for Vim.
   Vim error exceptions are parameterized with the name of the command that
failed, if known.  See |catch-errors|.


PECULIARITIES

                                                        *except-compat*
The exception handling concept requires that the command sequence causing the
exception is aborted immediately and control is transferred to finally clauses
and/or a catch clause.

In the Vim script language there are cases where scripts and functions
continue after an error: in functions without the "abort" flag or in a command
after ":silent!", control flow goes to the following line, and outside
functions, control flow goes to the line following the outermost ":endwhile"
or ":endif".  On the other hand, errors should be catchable as exceptions
(thus, requiring the immediate abortion).

This problem has been solved by converting errors to exceptions and using
immediate abortion (if not suppressed by ":silent!") only when a try
conditional is active.  This is no restriction since an (error) exception can
be caught only from an active try conditional.  If you want an immediate
termination without catching the error, just use a try conditional without
catch clause.  (You can cause cleanup code being executed before termination
by specifying a finally clause.)

When no try conditional is active, the usual abortion and continuation
behavior is used instead of immediate abortion.  This ensures compatibility of
scripts written for Vim 6.1 and earlier.

However, when sourcing an existing script that does not use exception handling
commands (or when calling one of its functions) from inside an active try
conditional of a new script, you might change the control flow of the existing
script on error.  You get the immediate abortion on error and can catch the
error in the new script.  If however the sourced script suppresses error
messages by using the ":silent!" command (checking for errors by testing
|v:errmsg| if appropriate), its execution path is not changed.  The error is
not converted to an exception.  (See |:silent|.)  So the only remaining cause
where this happens is for scripts that don't care about errors and produce
error messages.  You probably won't want to use such code from your new
scripts.


                                                        *except-syntax-err*
Syntax errors in the exception handling commands are never caught by any of
the ":catch" commands of the try conditional they belong to.  Its finally
clauses, however, is executed.
   Example:

     :try
     :  try
     :    throw 4711
     :  catch /\(/
     :    echo "in catch with syntax error"
     :  catch
     :    echo "inner catch-all"
     :  finally
     :    echo "inner finally"
     :  endtry
     :catch
     :  echo 'outer catch-all caught "' . v:exception . '"'
     :  finally
     :    echo "outer finally"
     :endtry

This displays:
    inner finally
    outer catch-all caught "Vim(catch):E54: Unmatched \("
    outer finally
The original exception is discarded and an error exception is raised, instead.


                                                        *except-single-line*
The ":try", ":catch", ":finally", and ":endtry" commands can be put on
a single line, but then syntax errors may make it difficult to recognize the
"catch" line, thus you better avoid this.
   Example:
     :try | unlet! foo # | catch | endtry
raises an error exception for the trailing characters after the ":unlet!"
argument, but does not see the ":catch" and ":endtry" commands, so that the
error exception is discarded and the "E488: Trailing characters" message gets
displayed.


                                                        *except-several-errors*
When several errors appear in a single command, the first error message is
usually the most specific one and therefor converted to the error exception.
   Example:
     echo novar
causes
     E121: Undefined variable: novar
     E15: Invalid expression: novar
The value of the error exception inside try conditionals is:
     Vim(echo):E121: Undefined variable: novar

                                                        *except-syntax-error*
But when a syntax error is detected after a normal error in the same command,
the syntax error is used for the exception being thrown.
   Example:
     unlet novar #
causes
     E108: No such variable: "novar"
     E488: Trailing characters
The value of the error exception inside try conditionals is:
     Vim(unlet):E488: Trailing characters
This is done because the syntax error might change the execution path in a way
not intended by the user.  Example:
     try
         try | unlet novar # | catch | echo v:exception | endtry
     catch /.*/
         echo "outer catch:" v:exception
     endtry
This displays "outer catch: Vim(unlet):E488: Trailing characters", and then
a "E600: Missing :endtry" error message is given, see |except-single-line|.

==============================================================================

9. Examples                                             *eval-examples*

Printing in Hex 

  :" The function Nr2Hex() returns the Hex string of a number.
  :func Nr2Hex(nr)
  :  let n = a:nr
  :  let r = ""
  :  while n
  :    let r = '0123456789ABCDEF'[n % 16] . r
  :    let n = n / 16
  :  endwhile
  :  return r
  :endfunc

  :" The function String2Hex() converts each character in a string to a two
  :" character Hex string.
  :func String2Hex(str)
  :  let out = ''
  :  let ix = 0
  :  while ix < strlen(a:str)
  :    let out = out . Nr2Hex(char2nr(a:str[ix]))
  :    let ix = ix + 1
  :  endwhile
  :  return out
  :endfunc

Example of its use:
  :echo Nr2Hex(32)
result: "20"
  :echo String2Hex("32")
result: "3332"


Sorting lines (by Robert Webb) 

Here is a Vim script to sort lines.  Highlight the lines in Vim and type
":Sort".  This doesn't call any external programs so it'll work on any
platform.  The function Sort() actually takes the name of a comparison
function as its argument, like qsort() does in C.  So you could supply it
with different comparison functions in order to sort according to date etc.

  :" Function for use with Sort(), to compare two strings.
  :func! Strcmp(str1, str2)
  :  if (a:str1 < a:str2)
  :  return -1
  :  elseif (a:str1 > a:str2)
  :  return 1
  :  else
  :  return 0
  :  endif
  :endfunction

  :" Sort lines.  SortR() is called recursively.
  :func! SortR(start, end, cmp)
  :  if (a:start >= a:end)
  :  return
  :  endif
  :  let partition = a:start - 1
  :  let middle = partition
  :  let partStr = getline((a:start + a:end) / 2)
  :  let i = a:start
  :  while (i <= a:end)
  :  let str = getline(i)
  :  exec "let result = " . a:cmp . "(str, partStr)"
  :  if (result <= 0)
  :      " Need to put it before the partition.  Swap lines i and partition.
  :      let partition = partition + 1
  :      if (result == 0)
  :          let middle = partition
  :      endif
  :      if (i != partition)
  :          let str2 = getline(partition)
  :          call setline(i, str2)
  :          call setline(partition, str)
  :      endif
  :  endif
  :  let i = i + 1
  :  endwhile

  :  " Now we have a pointer to the "middle" element, as far as partitioning
  :  " goes, which could be anywhere before the partition.  Make sure it is at
  :  " the end of the partition.
  :  if (middle != partition)
  :  let str = getline(middle)
  :  let str2 = getline(partition)
  :  call setline(middle, str2)
  :  call setline(partition, str)
  :  endif
  :  call SortR(a:start, partition - 1, a:cmp)
  :  call SortR(partition + 1, a:end, a:cmp)
  :endfunc

  :" To Sort a range of lines, pass the range to Sort() along with the name of a
  :" function that will compare two lines.
  :func! Sort(cmp) range
  :  call SortR(a:firstline, a:lastline, a:cmp)
  :endfunc

  :" :Sort takes a range of lines and sorts them.
  :command! -nargs=0 -range Sort <line1>,<line2>call Sort("Strcmp")
 

                                                        *sscanf*
There is no sscanf() function in Vim.  If you need to extract parts from a
line, you can use matchstr() and substitute() to do it.  This example shows
how to get the file name, line number and column number out of a line like
"foobar.txt, 123, 45".
   :" Set up the match bit
   :let mx='\(\f\+\),\s*\(\d\+\),\s*\(\d\+\)'
   :"get the part matching the whole expression
   :let l = matchstr(line, mx)
   :"get each item out of the match
   :let file = substitute(l, mx, '\1', '')
   :let lnum = substitute(l, mx, '\2', '')
   :let col = substitute(l, mx, '\3', '')

The input is in the variable "line", the results in the variables "file",
"lnum" and "col". (idea from Michael Geddes)

==============================================================================

10. No +eval feature                           *no-eval-feature*

When the |+eval| feature was disabled at compile time, none of the expression
evaluation commands are available.  To prevent this from causing Vim scripts
to generate all kinds of errors, the ":if" and ":endif" commands are still
recognized, though the argument of the ":if" and everything between the ":if"
and the matching ":endif" is ignored.  Nesting of ":if" blocks is allowed, but
only if the commands are at the start of the line.  The ":else" command is not
recognized.

Example of how to avoid executing commands when the |+eval| feature is
missing:

     :if 1
     :  echo "Expression evaluation is compiled in"
     :else
     :  echo "You will _never_ see this message"
     :endif

==============================================================================

11. The sandbox                                  *eval-sandbox* *sandbox* *E48*

The 'foldexpr', 'includeexpr', 'indentexpr', 'statusline' and 'foldtext'
options are evaluated in a sandbox.  This means that you are protected from
these expressions having nasty side effects.  This gives some safety for when
these options are set from a modeline.  It is also used when the command from
a tags file is executed and for CTRL-R = in the command line.
The sandbox is also used for the |:sandbox| command.

These items are not allowed in the sandbox:
        - changing the buffer text
        - defining or changing mapping, autocommands, functions, user commands
        - setting certain options (see |option-summary|)
        - executing a shell command
        - reading or writing a file
        - jumping to another buffer or editing a file
        - executing Python, Perl, etc. commands
This is not guaranteed 100% secure, but it should block most attacks.


                                                        *:san* *:sandbox*
:san[dbox] {cmd}        Execute {cmd} in the sandbox.  Useful to evaluate an
                        option that may have been set from a modeline, e.g.
                        'foldexpr'.


                                                        *sandbox-option*
A few options contain an expression.  When this expression is evaluated it may
have to be done in the sandbox to avoid a security risk.  But the sandbox is
restrictive, thus this only happens when the option was set from an insecure
location.  Insecure in this context are:
- sourcing a .vimrc or .exrc in the current directory
- while executing in the sandbox
- value coming from a modeline

Note that when in the sandbox and saving an option value and restoring it, the
option will still be marked as it was set in the sandbox.

==============================================================================

12. Textlock                                                    *textlock*

In a few situations it is not allowed to change the text in the buffer, jump
to another window and some other things that might confuse or break what Vim
is currently doing.  This mostly applies to things that happen when Vim is
actually doing something else.  For example, evaluating the 'balloonexpr' may
happen any moment the mouse cursor is resting at some position.

This is not allowed when the textlock is active:
        - changing the buffer text
        - jumping to another buffer or window
        - editing another file
        - closing a window or quitting Vim
        - etc.


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