xref: /vim-8.2.3635/runtime/doc/eval.txt (revision c0197e28)
1*eval.txt*      For Vim version 7.0aa.  Last change: 2004 Sep 13
2
3
4		  VIM REFERENCE MANUAL    by Bram Moolenaar
5
6
7Expression evaluation			*expression* *expr* *E15* *eval*
8
9Using expressions is introduced in chapter 41 of the user manual |usr_41.txt|.
10
11Note: Expression evaluation can be disabled at compile time.  If this has been
12done, the features in this document are not available.  See |+eval| and the
13last chapter below.
14
151.  Variables		|variables|
162.  Expression syntax	|expression-syntax|
173.  Internal variable	|internal-variables|
184.  Builtin Functions	|functions|
195.  Defining functions	|user-functions|
206.  Curly braces names	|curly-braces-names|
217.  Commands		|expression-commands|
228.  Exception handling	|exception-handling|
239.  Examples		|eval-examples|
2410. No +eval feature	|no-eval-feature|
2511. The sandbox		|eval-sandbox|
26
27{Vi does not have any of these commands}
28
29==============================================================================
301. Variables						*variables*
31
32There are two types of variables:
33
34Number		a 32 bit signed number.
35String		a NUL terminated string of 8-bit unsigned characters.
36
37These are converted automatically, depending on how they are used.
38
39Conversion from a Number to a String is by making the ASCII representation of
40the Number.  Examples: >
41	Number 123	-->	String "123"
42	Number 0	-->	String "0"
43	Number -1	-->	String "-1"
44
45Conversion from a String to a Number is done by converting the first digits
46to a number.  Hexadecimal "0xf9" and Octal "017" numbers are recognized.  If
47the String doesn't start with digits, the result is zero.  Examples: >
48	String "456"	-->	Number 456
49	String "6bar"	-->	Number 6
50	String "foo"	-->	Number 0
51	String "0xf1"	-->	Number 241
52	String "0100"	-->	Number 64
53	String "-8"	-->	Number -8
54	String "+8"	-->	Number 0
55
56To force conversion from String to Number, add zero to it: >
57	:echo "0100" + 0
58
59For boolean operators Numbers are used.  Zero is FALSE, non-zero is TRUE.
60
61Note that in the command >
62	:if "foo"
63"foo" is converted to 0, which means FALSE.  To test for a non-empty string,
64use strlen(): >
65	:if strlen("foo")
66
67If you need to know the type of a variable or expression, use the |type()|
68function.
69
70When the '!' flag is included in the 'viminfo' option, global variables that
71start with an uppercase letter, and don't contain a lowercase letter, are
72stored in the viminfo file |viminfo-file|.
73
74When the 'sessionoptions' option contains "global", global variables that
75start with an uppercase letter and contain at least one lowercase letter are
76stored in the session file |session-file|.
77
78variable name		can be stored where ~
79my_var_6		not
80My_Var_6		session file
81MY_VAR_6		viminfo file
82
83
84It's possible to form a variable name with curly braces, see
85|curly-braces-names|.
86
87==============================================================================
882. Expression syntax					*expression-syntax*
89
90Expression syntax summary, from least to most significant:
91
92|expr1| expr2 ? expr1 : expr1	if-then-else
93
94|expr2|	expr3 || expr3 ..	logical OR
95
96|expr3|	expr4 && expr4 ..	logical AND
97
98|expr4|	expr5 == expr5		equal
99	expr5 != expr5		not equal
100	expr5 >	 expr5		greater than
101	expr5 >= expr5		greater than or equal
102	expr5 <	 expr5		smaller than
103	expr5 <= expr5		smaller than or equal
104	expr5 =~ expr5		regexp matches
105	expr5 !~ expr5		regexp doesn't match
106
107	expr5 ==? expr5		equal, ignoring case
108	expr5 ==# expr5		equal, match case
109	etc.			As above, append ? for ignoring case, # for
110				matching case
111
112|expr5|	expr6 +	 expr6 ..	number addition
113	expr6 -	 expr6 ..	number subtraction
114	expr6 .	 expr6 ..	string concatenation
115
116|expr6|	expr7 *	 expr7 ..	number multiplication
117	expr7 /	 expr7 ..	number division
118	expr7 %	 expr7 ..	number modulo
119
120|expr7|	! expr7			logical NOT
121	- expr7			unary minus
122	+ expr7			unary plus
123	expr8
124
125|expr8|	expr9[expr1]		index in String
126
127|expr9|	number			number constant
128	"string"		string constant
129	'string'		literal string constant
130	&option			option value
131	(expr1)			nested expression
132	variable		internal variable
133	va{ria}ble		internal variable with curly braces
134	$VAR			environment variable
135	@r			contents of register 'r'
136	function(expr1, ...)	function call
137	func{ti}on(expr1, ...)	function call with curly braces
138
139
140".." indicates that the operations in this level can be concatenated.
141Example: >
142	&nu || &list && &shell == "csh"
143
144All expressions within one level are parsed from left to right.
145
146
147expr1							*expr1* *E109*
148-----
149
150expr2 ? expr1 : expr1
151
152The expression before the '?' is evaluated to a number.  If it evaluates to
153non-zero, the result is the value of the expression between the '?' and ':',
154otherwise the result is the value of the expression after the ':'.
155Example: >
156	:echo lnum == 1 ? "top" : lnum
157
158Since the first expression is an "expr2", it cannot contain another ?:.  The
159other two expressions can, thus allow for recursive use of ?:.
160Example: >
161	:echo lnum == 1 ? "top" : lnum == 1000 ? "last" : lnum
162
163To keep this readable, using |line-continuation| is suggested: >
164	:echo lnum == 1
165	:\	? "top"
166	:\	: lnum == 1000
167	:\		? "last"
168	:\		: lnum
169
170
171expr2 and expr3						*expr2* *expr3*
172---------------
173
174					*expr-barbar* *expr-&&*
175The "||" and "&&" operators take one argument on each side.  The arguments
176are (converted to) Numbers.  The result is:
177
178	 input				 output ~
179n1		n2		n1 || n2	n1 && n2 ~
180zero		zero		zero		zero
181zero		non-zero	non-zero	zero
182non-zero	zero		non-zero	zero
183non-zero	non-zero	non-zero	non-zero
184
185The operators can be concatenated, for example: >
186
187	&nu || &list && &shell == "csh"
188
189Note that "&&" takes precedence over "||", so this has the meaning of: >
190
191	&nu || (&list && &shell == "csh")
192
193Once the result is known, the expression "short-circuits", that is, further
194arguments are not evaluated.  This is like what happens in C.  For example: >
195
196	let a = 1
197	echo a || b
198
199This is valid even if there is no variable called "b" because "a" is non-zero,
200so the result must be non-zero.  Similarly below: >
201
202	echo exists("b") && b == "yes"
203
204This is valid whether "b" has been defined or not.  The second clause will
205only be evaluated if "b" has been defined.
206
207
208expr4							*expr4*
209-----
210
211expr5 {cmp} expr5
212
213Compare two expr5 expressions, resulting in a 0 if it evaluates to false, or 1
214if it evaluates to true.
215
216			*expr-==*  *expr-!=*  *expr->*   *expr->=*
217			*expr-<*   *expr-<=*  *expr-=~*  *expr-!~*
218			*expr-==#* *expr-!=#* *expr->#*  *expr->=#*
219			*expr-<#*  *expr-<=#* *expr-=~#* *expr-!~#*
220			*expr-==?* *expr-!=?* *expr->?*  *expr->=?*
221			*expr-<?*  *expr-<=?* *expr-=~?* *expr-!~?*
222		use 'ignorecase'    match case	   ignore case ~
223equal			==		==#		==?
224not equal		!=		!=#		!=?
225greater than		>		>#		>?
226greater than or equal	>=		>=#		>=?
227smaller than		<		<#		<?
228smaller than or equal	<=		<=#		<=?
229regexp matches		=~		=~#		=~?
230regexp doesn't match	!~		!~#		!~?
231
232Examples:
233"abc" ==# "Abc"	  evaluates to 0
234"abc" ==? "Abc"	  evaluates to 1
235"abc" == "Abc"	  evaluates to 1 if 'ignorecase' is set, 0 otherwise
236
237When comparing a String with a Number, the String is converted to a Number,
238and the comparison is done on Numbers.  This means that "0 == 'x'" is TRUE,
239because 'x' converted to a Number is zero.
240
241When comparing two Strings, this is done with strcmp() or stricmp().  This
242results in the mathematical difference (comparing byte values), not
243necessarily the alphabetical difference in the local language.
244
245When using the operators with a trailing '#", or the short version and
246'ignorecase' is off, the comparing is done with strcmp().
247
248When using the operators with a trailing '?', or the short version and
249'ignorecase' is set, the comparing is done with stricmp().
250
251The "=~" and "!~" operators match the lefthand argument with the righthand
252argument, which is used as a pattern.  See |pattern| for what a pattern is.
253This matching is always done like 'magic' was set and 'cpoptions' is empty, no
254matter what the actual value of 'magic' or 'cpoptions' is.  This makes scripts
255portable.  To avoid backslashes in the regexp pattern to be doubled, use a
256single-quote string, see |literal-string|.
257Since a string is considered to be a single line, a multi-line pattern
258(containing \n, backslash-n) will not match.  However, a literal NL character
259can be matched like an ordinary character.  Examples:
260	"foo\nbar" =~ "\n"	evaluates to 1
261	"foo\nbar" =~ "\\n"	evaluates to 0
262
263
264expr5 and expr6						*expr5* *expr6*
265---------------
266expr6 +	 expr6 ..	number addition		*expr-+*
267expr6 -	 expr6 ..	number subtraction	*expr--*
268expr6 .	 expr6 ..	string concatenation	*expr-.*
269
270expr7 *	 expr7 ..	number multiplication	*expr-star*
271expr7 /	 expr7 ..	number division		*expr-/*
272expr7 %	 expr7 ..	number modulo		*expr-%*
273
274For all, except ".", Strings are converted to Numbers.
275
276Note the difference between "+" and ".":
277	"123" + "456" = 579
278	"123" . "456" = "123456"
279
280When the righthand side of '/' is zero, the result is 0x7fffffff.
281When the righthand side of '%' is zero, the result is 0.
282
283
284expr7							*expr7*
285-----
286! expr7			logical NOT		*expr-!*
287- expr7			unary minus		*expr-unary--*
288+ expr7			unary plus		*expr-unary-+*
289
290For '!' non-zero becomes zero, zero becomes one.
291For '-' the sign of the number is changed.
292For '+' the number is unchanged.
293
294A String will be converted to a Number first.
295
296These three can be repeated and mixed.  Examples:
297	!-1	    == 0
298	!!8	    == 1
299	--9	    == 9
300
301
302expr8							*expr8*
303-----
304expr9[expr1]		index in String		*expr-[]* *E111*
305
306This results in a String that contains the expr1'th single byte from expr9.
307expr9 is used as a String, expr1 as a Number.  Note that this doesn't work for
308multi-byte encodings.
309
310Note that index zero gives the first character.  This is like it works in C.
311Careful: text column numbers start with one!  Example, to get the character
312under the cursor: >
313	:let c = getline(line("."))[col(".") - 1]
314
315If the length of the String is less than the index, the result is an empty
316String.
317
318						*expr9*
319number
320------
321number			number constant		*expr-number*
322
323Decimal, Hexadecimal (starting with 0x or 0X), or Octal (starting with 0).
324
325
326string							*expr-string* *E114*
327------
328"string"		string constant		*expr-quote*
329
330Note that double quotes are used.
331
332A string constant accepts these special characters:
333\...	three-digit octal number (e.g., "\316")
334\..	two-digit octal number (must be followed by non-digit)
335\.	one-digit octal number (must be followed by non-digit)
336\x..	byte specified with two hex numbers (e.g., "\x1f")
337\x.	byte specified with one hex number (must be followed by non-hex char)
338\X..	same as \x..
339\X.	same as \x.
340\u....  character specified with up to 4 hex numbers, stored according to the
341	current value of 'encoding' (e.g., "\u02a4")
342\U....	same as \u....
343\b	backspace <BS>
344\e	escape <Esc>
345\f	formfeed <FF>
346\n	newline <NL>
347\r	return <CR>
348\t	tab <Tab>
349\\	backslash
350\"	double quote
351\<xxx>	Special key named "xxx".  e.g. "\<C-W>" for CTRL-W.
352
353Note that "\000" and "\x00" force the end of the string.
354
355
356literal-string						*literal-string* *E115*
357---------------
358'string'		literal string constant		*expr-'*
359
360Note that single quotes are used.
361
362This string is taken literally.  No backslashes are removed or have a special
363meaning.  A literal-string cannot contain a single quote.  Use a normal string
364for that.
365
366
367option						*expr-option* *E112* *E113*
368------
369&option			option value, local value if possible
370&g:option		global option value
371&l:option		local option value
372
373Examples: >
374	echo "tabstop is " . &tabstop
375	if &insertmode
376
377Any option name can be used here.  See |options|.  When using the local value
378and there is no buffer-local or window-local value, the global value is used
379anyway.
380
381
382register						*expr-register*
383--------
384@r			contents of register 'r'
385
386The result is the contents of the named register, as a single string.
387Newlines are inserted where required.  To get the contents of the unnamed
388register use @" or @@.  The '=' register can not be used here.  See
389|registers| for an explanation of the available registers.
390
391
392nesting							*expr-nesting* *E110*
393-------
394(expr1)			nested expression
395
396
397environment variable					*expr-env*
398--------------------
399$VAR			environment variable
400
401The String value of any environment variable.  When it is not defined, the
402result is an empty string.
403						*expr-env-expand*
404Note that there is a difference between using $VAR directly and using
405expand("$VAR").  Using it directly will only expand environment variables that
406are known inside the current Vim session.  Using expand() will first try using
407the environment variables known inside the current Vim session.  If that
408fails, a shell will be used to expand the variable.  This can be slow, but it
409does expand all variables that the shell knows about.  Example: >
410	:echo $version
411	:echo expand("$version")
412The first one probably doesn't echo anything, the second echoes the $version
413variable (if your shell supports it).
414
415
416internal variable					*expr-variable*
417-----------------
418variable		internal variable
419See below |internal-variables|.
420
421
422function call		*expr-function* *E116* *E117* *E118* *E119* *E120*
423-------------
424function(expr1, ...)	function call
425See below |functions|.
426
427
428==============================================================================
4293. Internal variable				*internal-variables* *E121*
430									*E461*
431An internal variable name can be made up of letters, digits and '_'.  But it
432cannot start with a digit.  It's also possible to use curly braces, see
433|curly-braces-names|.
434
435An internal variable is created with the ":let" command |:let|.
436An internal variable is destroyed with the ":unlet" command |:unlet|.
437Using a name that isn't an internal variable, or an internal variable that has
438been destroyed, results in an error.
439
440There are several name spaces for variables.  Which one is to be used is
441specified by what is prepended:
442
443		(nothing) In a function: local to a function; otherwise: global
444|buffer-variable|    b:	  Local to the current buffer.
445|window-variable|    w:	  Local to the current window.
446|global-variable|    g:	  Global.
447|local-variable|     l:	  Local to a function.
448|script-variable|    s:	  Local to a |:source|'ed Vim script.
449|function-argument|  a:	  Function argument (only inside a function).
450|vim-variable|       v:	  Global, predefined by Vim.
451
452						*buffer-variable* *b:var*
453A variable name that is preceded with "b:" is local to the current buffer.
454Thus you can have several "b:foo" variables, one for each buffer.
455This kind of variable is deleted when the buffer is wiped out or deleted with
456|:bdelete|.
457
458One local buffer variable is predefined:
459					*b:changedtick-variable* *changetick*
460b:changedtick	The total number of changes to the current buffer.  It is
461		incremented for each change.  An undo command is also a change
462		in this case.  This can be used to perform an action only when
463		the buffer has changed.  Example: >
464		    :if my_changedtick != b:changedtick
465		    :   let my_changedtick = b:changedtick
466		    :   call My_Update()
467		    :endif
468<
469						*window-variable* *w:var*
470A variable name that is preceded with "w:" is local to the current window.  It
471is deleted when the window is closed.
472
473						*global-variable* *g:var*
474Inside functions global variables are accessed with "g:".  Omitting this will
475access a variable local to a function.  But "g:" can also be used in any other
476place if you like.
477
478						*local-variable* *l:var*
479Inside functions local variables are accessed without prepending anything.
480But you can also prepend "l:" if you like.
481
482						*script-variable* *s:var*
483In a Vim script variables starting with "s:" can be used.  They cannot be
484accessed from outside of the scripts, thus are local to the script.
485
486They can be used in:
487- commands executed while the script is sourced
488- functions defined in the script
489- autocommands defined in the script
490- functions and autocommands defined in functions and autocommands which were
491  defined in the script (recursively)
492- user defined commands defined in the script
493Thus not in:
494- other scripts sourced from this one
495- mappings
496- etc.
497
498script variables can be used to avoid conflicts with global variable names.
499Take this example:
500
501	let s:counter = 0
502	function MyCounter()
503	  let s:counter = s:counter + 1
504	  echo s:counter
505	endfunction
506	command Tick call MyCounter()
507
508You can now invoke "Tick" from any script, and the "s:counter" variable in
509that script will not be changed, only the "s:counter" in the script where
510"Tick" was defined is used.
511
512Another example that does the same: >
513
514	let s:counter = 0
515	command Tick let s:counter = s:counter + 1 | echo s:counter
516
517When calling a function and invoking a user-defined command, the context for
518script variables is set to the script where the function or command was
519defined.
520
521The script variables are also available when a function is defined inside a
522function that is defined in a script.  Example: >
523
524	let s:counter = 0
525	function StartCounting(incr)
526	  if a:incr
527	    function MyCounter()
528	      let s:counter = s:counter + 1
529	    endfunction
530	  else
531	    function MyCounter()
532	      let s:counter = s:counter - 1
533	    endfunction
534	  endif
535	endfunction
536
537This defines the MyCounter() function either for counting up or counting down
538when calling StartCounting().  It doesn't matter from where StartCounting() is
539called, the s:counter variable will be accessible in MyCounter().
540
541When the same script is sourced again it will use the same script variables.
542They will remain valid as long as Vim is running.  This can be used to
543maintain a counter: >
544
545	if !exists("s:counter")
546	  let s:counter = 1
547	  echo "script executed for the first time"
548	else
549	  let s:counter = s:counter + 1
550	  echo "script executed " . s:counter . " times now"
551	endif
552
553Note that this means that filetype plugins don't get a different set of script
554variables for each buffer.  Use local buffer variables instead |b:var|.
555
556
557Predefined Vim variables:			*vim-variable* *v:var*
558
559			*v:charconvert_from* *charconvert_from-variable*
560v:charconvert_from
561		The name of the character encoding of a file to be converted.
562		Only valid while evaluating the 'charconvert' option.
563
564			*v:charconvert_to* *charconvert_to-variable*
565v:charconvert_to
566		The name of the character encoding of a file after conversion.
567		Only valid while evaluating the 'charconvert' option.
568
569					*v:cmdarg* *cmdarg-variable*
570v:cmdarg	This variable is used for two purposes:
571		1. The extra arguments given to a file read/write command.
572		   Currently these are "++enc=" and "++ff=".  This variable is
573		   set before an autocommand event for a file read/write
574		   command is triggered.  There is a leading space to make it
575		   possible to append this variable directly after the
576		   read/write command.  Note: The "+cmd" argument isn't
577		   included here, because it will be executed anyway.
578		2. When printing a PostScript file with ":hardcopy" this is
579		   the argument for the ":hardcopy" command.  This can be used
580		   in 'printexpr'.
581
582					*v:cmdbang* *cmdbang-variable*
583v:cmdbang	Set like v:cmdarg for a file read/write command.  When a "!"
584		was used the value is 1, otherwise it is 0.  Note that this
585		can only be used in autocommands.  For user commands |<bang>|
586		can be used.
587
588					*v:count* *count-variable*
589v:count		The count given for the last Normal mode command.  Can be used
590		to get the count before a mapping.  Read-only.  Example: >
591	:map _x :<C-U>echo "the count is " . v:count<CR>
592<		Note: The <C-U> is required to remove the line range that you
593		get when typing ':' after a count.
594		"count" also works, for backwards compatibility.
595
596					*v:count1* *count1-variable*
597v:count1	Just like "v:count", but defaults to one when no count is
598		used.
599
600						*v:ctype* *ctype-variable*
601v:ctype		The current locale setting for characters of the runtime
602		environment.  This allows Vim scripts to be aware of the
603		current locale encoding.  Technical: it's the value of
604		LC_CTYPE.  When not using a locale the value is "C".
605		This variable can not be set directly, use the |:language|
606		command.
607		See |multi-lang|.
608
609					*v:dying* *dying-variable*
610v:dying		Normally zero.  When a deadly signal is caught it's set to
611		one.  When multiple signals are caught the number increases.
612		Can be used in an autocommand to check if Vim didn't
613		terminate normally. {only works on Unix}
614		Example: >
615	:au VimLeave * if v:dying | echo "\nAAAAaaaarrrggghhhh!!!\n" | endif
616<
617					*v:errmsg* *errmsg-variable*
618v:errmsg	Last given error message.  It's allowed to set this variable.
619		Example: >
620	:let v:errmsg = ""
621	:silent! next
622	:if v:errmsg != ""
623	:  ... handle error
624<		"errmsg" also works, for backwards compatibility.
625
626					*v:exception* *exception-variable*
627v:exception	The value of the exception most recently caught and not
628		finished.  See also |v:throwpoint| and |throw-variables|.
629		Example: >
630	:try
631	:  throw "oops"
632	:catch /.*/
633	:  echo "caught" v:exception
634	:endtry
635<		Output: "caught oops".
636
637					*v:fname_in* *fname_in-variable*
638v:fname_in	The name of the input file.  Only valid while evaluating:
639			option		used for ~
640			'charconvert'	file to be converted
641			'diffexpr'	original file
642			'patchexpr'	original file
643			'printexpr'	file to be printed
644
645					*v:fname_out* *fname_out-variable*
646v:fname_out	The name of the output file.  Only valid while
647		evaluating:
648			option		used for ~
649			'charconvert'	resulting converted file (*)
650			'diffexpr'	output of diff
651			'patchexpr'	resulting patched file
652		(*) When doing conversion for a write command (e.g., ":w
653		file") it will be equal to v:fname_in.  When doing conversion
654		for a read command (e.g., ":e file") it will be a temporary
655		file and different from v:fname_in.
656
657					*v:fname_new* *fname_new-variable*
658v:fname_new	The name of the new version of the file.  Only valid while
659		evaluating 'diffexpr'.
660
661					*v:fname_diff* *fname_diff-variable*
662v:fname_diff	The name of the diff (patch) file.  Only valid while
663		evaluating 'patchexpr'.
664
665					*v:folddashes* *folddashes-variable*
666v:folddashes	Used for 'foldtext': dashes representing foldlevel of a closed
667		fold.
668		Read-only. |fold-foldtext|
669
670					*v:foldlevel* *foldlevel-variable*
671v:foldlevel	Used for 'foldtext': foldlevel of closed fold.
672		Read-only. |fold-foldtext|
673
674					*v:foldend* *foldend-variable*
675v:foldend	Used for 'foldtext': last line of closed fold.
676		Read-only. |fold-foldtext|
677
678					*v:foldstart* *foldstart-variable*
679v:foldstart	Used for 'foldtext': first line of closed fold.
680		Read-only. |fold-foldtext|
681
682					*v:insertmode* *insertmode-variable*
683v:insertmode	Used for the |InsertEnter| and |InsertChange| autocommand
684		events.  Values:
685			i	Insert mode
686			r	Replace mode
687			v	Virtual Replace mode
688
689						*v:lang* *lang-variable*
690v:lang		The current locale setting for messages of the runtime
691		environment.  This allows Vim scripts to be aware of the
692		current language.  Technical: it's the value of LC_MESSAGES.
693		The value is system dependent.
694		This variable can not be set directly, use the |:language|
695		command.
696		It can be different from |v:ctype| when messages are desired
697		in a different language than what is used for character
698		encoding.  See |multi-lang|.
699
700						*v:lc_time* *lc_time-variable*
701v:lc_time	The current locale setting for time messages of the runtime
702		environment.  This allows Vim scripts to be aware of the
703		current language.  Technical: it's the value of LC_TIME.
704		This variable can not be set directly, use the |:language|
705		command.  See |multi-lang|.
706
707						*v:lnum* *lnum-variable*
708v:lnum		Line number for the 'foldexpr' and 'indentexpr' expressions.
709		Only valid while one of these expressions is being evaluated.
710		Read-only. |fold-expr| 'indentexpr'
711
712					*v:prevcount* *prevcount-variable*
713v:prevcount	The count given for the last but one Normal mode command.
714		This is the v:count value of the previous command.  Useful if
715		you want to cancel Visual mode and then use the count. >
716			:vmap % <Esc>:call MyFilter(v:prevcount)<CR>
717<		Read-only.
718
719					*v:progname* *progname-variable*
720v:progname	Contains the name (with path removed) with which Vim was
721		invoked.  Allows you to do special initialisations for "view",
722		"evim" etc., or any other name you might symlink to Vim.
723		Read-only.
724
725					*v:register* *register-variable*
726v:register	The name of the register supplied to the last normal mode
727		command.  Empty if none were supplied. |getreg()| |setreg()|
728
729					*v:servername* *servername-variable*
730v:servername	The resulting registered |x11-clientserver| name if any.
731		Read-only.
732
733					*v:shell_error* *shell_error-variable*
734v:shell_error	Result of the last shell command.  When non-zero, the last
735		shell command had an error.  When zero, there was no problem.
736		This only works when the shell returns the error code to Vim.
737		The value -1 is often used when the command could not be
738		executed.  Read-only.
739		Example: >
740	:!mv foo bar
741	:if v:shell_error
742	:  echo 'could not rename "foo" to "bar"!'
743	:endif
744<		"shell_error" also works, for backwards compatibility.
745
746					*v:statusmsg* *statusmsg-variable*
747v:statusmsg	Last given status message.  It's allowed to set this variable.
748
749				*v:termresponse* *termresponse-variable*
750v:termresponse	The escape sequence returned by the terminal for the |t_RV|
751		termcap entry.  It is set when Vim receives an escape sequence
752		that starts with ESC [ or CSI and ends in a 'c', with only
753		digits, ';' and '.' in between.
754		When this option is set, the TermResponse autocommand event is
755		fired, so that you can react to the response from the
756		terminal.
757		The response from a new xterm is: "<Esc>[ Pp ; Pv ; Pc c".  Pp
758		is the terminal type: 0 for vt100 and 1 for vt220.  Pv is the
759		patch level (since this was introduced in patch 95, it's
760		always 95 or bigger).  Pc is always zero.
761		{only when compiled with |+termresponse| feature}
762
763				*v:this_session* *this_session-variable*
764v:this_session	Full filename of the last loaded or saved session file.  See
765		|:mksession|.  It is allowed to set this variable.  When no
766		session file has been saved, this variable is empty.
767		"this_session" also works, for backwards compatibility.
768
769					*v:throwpoint* *throwpoint-variable*
770v:throwpoint	The point where the exception most recently caught and not
771		finished was thrown.  Not set when commands are typed.  See
772		also |v:exception| and |throw-variables|.
773		Example: >
774	:try
775	:  throw "oops"
776	:catch /.*/
777	:  echo "Exception from" v:throwpoint
778	:endtry
779<		Output: "Exception from test.vim, line 2"
780
781					*v:version* *version-variable*
782v:version	Version number of Vim: Major version number times 100 plus
783		minor version number.  Version 5.0 is 500.  Version 5.1 (5.01)
784		is 501.  Read-only.  "version" also works, for backwards
785		compatibility.
786		Use |has()| to check if a certain patch was included, e.g.: >
787			if has("patch123")
788<		Note that patch numbers are specific to the version, thus both
789		version 5.0 and 5.1 may have a patch 123, but these are
790		completely different.
791
792					*v:warningmsg* *warningmsg-variable*
793v:warningmsg	Last given warning message.  It's allowed to set this variable.
794
795==============================================================================
7964. Builtin Functions					*functions*
797
798See |function-list| for a list grouped by what the function is used for.
799
800(Use CTRL-] on the function name to jump to the full explanation)
801
802USAGE				RESULT	DESCRIPTION	~
803
804append( {lnum}, {string})	Number  append {string} below line {lnum}
805argc()				Number	number of files in the argument list
806argidx()			Number  current index in the argument list
807argv( {nr})			String	{nr} entry of the argument list
808browse( {save}, {title}, {initdir}, {default})
809				String	put up a file requester
810bufexists( {expr})		Number	TRUE if buffer {expr} exists
811buflisted( {expr})		Number  TRUE if buffer {expr} is listed
812bufloaded( {expr})		Number  TRUE if buffer {expr} is loaded
813bufname( {expr})		String	Name of the buffer {expr}
814bufnr( {expr})			Number	Number of the buffer {expr}
815bufwinnr( {expr})		Number	window number of buffer {expr}
816byte2line( {byte})		Number	line number at byte count {byte}
817byteidx( {expr}, {nr})		Number  byte index of {nr}'th char in {expr}
818char2nr( {expr})		Number	ASCII value of first char in {expr}
819cindent( {lnum})		Number  C indent for line {lnum}
820col( {expr})			Number	column nr of cursor or mark
821confirm( {msg} [, {choices} [, {default} [, {type}]]])
822				Number	number of choice picked by user
823cscope_connection( [{num} , {dbpath} [, {prepend}]])
824				Number	checks existence of cscope connection
825cursor( {lnum}, {col})		Number  position cursor at {lnum}, {col}
826delete( {fname})		Number	delete file {fname}
827did_filetype()			Number	TRUE if FileType autocommand event used
828escape( {string}, {chars})	String	escape {chars} in {string} with '\'
829eventhandler( )			Number  TRUE if inside an event handler
830executable( {expr})		Number	1 if executable {expr} exists
831exists( {expr})			Number	TRUE if {expr} exists
832expand( {expr})			String	expand special keywords in {expr}
833filereadable( {file})		Number	TRUE if {file} is a readable file
834findfile( {name}[, {path}[, {count}]])
835				String  Find fine {name} in {path}
836filewritable( {file})		Number	TRUE if {file} is a writable file
837fnamemodify( {fname}, {mods})	String	modify file name
838foldclosed( {lnum})		Number  first line of fold at {lnum} if closed
839foldclosedend( {lnum})		Number  last line of fold at {lnum} if closed
840foldlevel( {lnum})		Number	fold level at {lnum}
841foldtext( )			String  line displayed for closed fold
842foreground( )			Number	bring the Vim window to the foreground
843getchar( [expr])		Number  get one character from the user
844getcharmod( )			Number  modifiers for the last typed character
845getbufvar( {expr}, {varname})		variable {varname} in buffer {expr}
846getcmdline()			String	return the current command-line
847getcmdpos()			Number	return cursor position in command-line
848getcwd()			String	the current working directory
849getfperm( {fname})		String	file permissions of file {fname}
850getfsize( {fname})		Number	size in bytes of file {fname}
851getftime( {fname})		Number	last modification time of file
852getftype( {fname})		String	description of type of file {fname}
853getline( {lnum})		String	line {lnum} from current buffer
854getreg( [{regname}])		String  contents of register
855getregtype( [{regname}])	String  type of register
856getwinposx()			Number	X coord in pixels of GUI Vim window
857getwinposy()			Number	Y coord in pixels of GUI Vim window
858getwinvar( {nr}, {varname})		variable {varname} in window {nr}
859glob( {expr})			String	expand file wildcards in {expr}
860globpath( {path}, {expr})	String	do glob({expr}) for all dirs in {path}
861has( {feature})			Number	TRUE if feature {feature} supported
862hasmapto( {what} [, {mode}])	Number	TRUE if mapping to {what} exists
863histadd( {history},{item})	String	add an item to a history
864histdel( {history} [, {item}])	String	remove an item from a history
865histget( {history} [, {index}])	String	get the item {index} from a history
866histnr( {history})		Number	highest index of a history
867hlexists( {name})		Number	TRUE if highlight group {name} exists
868hlID( {name})			Number	syntax ID of highlight group {name}
869hostname()			String	name of the machine Vim is running on
870iconv( {expr}, {from}, {to})	String  convert encoding of {expr}
871indent( {lnum})			Number  indent of line {lnum}
872input( {prompt} [, {text}])	String	get input from the user
873inputdialog( {p} [, {t} [, {c}]]) String  like input() but in a GUI dialog
874inputrestore()			Number  restore typeahead
875inputsave()			Number  save and clear typeahead
876inputsecret( {prompt} [, {text}]) String  like input() but hiding the text
877isdirectory( {directory})	Number	TRUE if {directory} is a directory
878libcall( {lib}, {func}, {arg})	String  call {func} in library {lib} with {arg}
879libcallnr( {lib}, {func}, {arg})  Number  idem, but return a Number
880line( {expr})			Number	line nr of cursor, last line or mark
881line2byte( {lnum})		Number	byte count of line {lnum}
882lispindent( {lnum})		Number  Lisp indent for line {lnum}
883localtime()			Number	current time
884maparg( {name}[, {mode}])	String	rhs of mapping {name} in mode {mode}
885mapcheck( {name}[, {mode}])	String	check for mappings matching {name}
886match( {expr}, {pat}[, {start}[, {count}]])
887				Number	position where {pat} matches in {expr}
888matchend( {expr}, {pat}[, {start}[, {count}]])
889				Number	position where {pat} ends in {expr}
890matchstr( {expr}, {pat}[, {start}[, {count}]])
891				String	{count}'th match of {pat} in {expr}
892mode()				String  current editing mode
893nextnonblank( {lnum})		Number	line nr of non-blank line >= {lnum}
894nr2char( {expr})		String	single char with ASCII value {expr}
895prevnonblank( {lnum})		Number	line nr of non-blank line <= {lnum}
896remote_expr( {server}, {string} [, {idvar}])
897				String	send expression
898remote_foreground( {server})	Number	bring Vim server to the foreground
899remote_peek( {serverid} [, {retvar}])
900				Number	check for reply string
901remote_read( {serverid})	String	read reply string
902remote_send( {server}, {string} [, {idvar}])
903				String	send key sequence
904rename( {from}, {to})		Number  rename (move) file from {from} to {to}
905repeat( {expr}, {count})	String  repeat {expr} {count} times
906resolve( {filename})		String  get filename a shortcut points to
907search( {pattern} [, {flags}])	Number  search for {pattern}
908searchpair( {start}, {middle}, {end} [, {flags} [, {skip}]])
909				Number  search for other end of start/end pair
910server2client( {clientid}, {string})
911				Number	send reply string
912serverlist()			String	get a list of available servers
913setbufvar( {expr}, {varname}, {val})	set {varname} in buffer {expr} to {val}
914setcmdpos( {pos})		Number	set cursor position in command-line
915setline( {lnum}, {line})	Number	set line {lnum} to {line}
916setreg( {n}, {v}[, {opt}])	Number  set register to value and type
917setwinvar( {nr}, {varname}, {val})	set {varname} in window {nr} to {val}
918simplify( {filename})		String  simplify filename as much as possible
919strftime( {format}[, {time}])	String	time in specified format
920stridx( {haystack}, {needle})	Number	first index of {needle} in {haystack}
921strlen( {expr})			Number	length of the String {expr}
922strpart( {src}, {start}[, {len}])
923				String	{len} characters of {src} at {start}
924strridx( {haystack}, {needle})	Number	last index of {needle} in {haystack}
925strtrans( {expr})		String	translate string to make it printable
926submatch( {nr})			String  specific match in ":substitute"
927substitute( {expr}, {pat}, {sub}, {flags})
928				String	all {pat} in {expr} replaced with {sub}
929synID( {line}, {col}, {trans})	Number	syntax ID at {line} and {col}
930synIDattr( {synID}, {what} [, {mode}])
931				String	attribute {what} of syntax ID {synID}
932synIDtrans( {synID})		Number	translated syntax ID of {synID}
933system( {expr} [, {input}])	String	output of shell command/filter {expr}
934tempname()			String	name for a temporary file
935tolower( {expr})		String	the String {expr} switched to lowercase
936toupper( {expr})		String	the String {expr} switched to uppercase
937tr( {src}, {fromstr}, {tostr})	String	translate chars of {src} in {fromstr}
938					to chars in {tostr}
939type( {name})			Number	type of variable {name}
940virtcol( {expr})		Number	screen column of cursor or mark
941visualmode( [expr])		String	last visual mode used
942winbufnr( {nr})			Number	buffer number of window {nr}
943wincol()			Number	window column of the cursor
944winheight( {nr})		Number	height of window {nr}
945winline()			Number	window line of the cursor
946winnr()				Number	number of current window
947winrestcmd()			String  returns command to restore window sizes
948winwidth( {nr})			Number	width of window {nr}
949
950append({lnum}, {string})				*append()*
951		Append the text {string} after line {lnum} in the current
952		buffer.  {lnum} can be zero, to insert a line before the first
953		one.  Returns 1 for failure ({lnum} out of range) or 0 for
954		success.
955
956							*argc()*
957argc()		The result is the number of files in the argument list of the
958		current window.  See |arglist|.
959
960							*argidx()*
961argidx()	The result is the current index in the argument list.  0 is
962		the first file.  argc() - 1 is the last one.  See |arglist|.
963
964							*argv()*
965argv({nr})	The result is the {nr}th file in the argument list of the
966		current window.  See |arglist|.  "argv(0)" is the first one.
967		Example: >
968	:let i = 0
969	:while i < argc()
970	:  let f = escape(argv(i), '. ')
971	:  exe 'amenu Arg.' . f . ' :e ' . f . '<CR>'
972	:  let i = i + 1
973	:endwhile
974<
975							*browse()*
976browse({save}, {title}, {initdir}, {default})
977		Put up a file requester.  This only works when "has("browse")"
978		returns non-zero (only in some GUI versions).
979		The input fields are:
980		    {save}	when non-zero, select file to write
981		    {title}	title for the requester
982		    {initdir}	directory to start browsing in
983		    {default}	default file name
984		When the "Cancel" button is hit, something went wrong, or
985		browsing is not possible, an empty string is returned.
986
987bufexists({expr})					*bufexists()*
988		The result is a Number, which is non-zero if a buffer called
989		{expr} exists.
990		If the {expr} argument is a number, buffer numbers are used.
991		If the {expr} argument is a string it must match a buffer name
992		exactly.  The name can be:
993		- Relative to the current directory.
994		- A full path.
995		- The name of a buffer with 'filetype' set to "nofile".
996		- A URL name.
997		Unlisted buffers will be found.
998		Note that help files are listed by their short name in the
999		output of |:buffers|, but bufexists() requires using their
1000		long name to be able to find them.
1001		Use "bufexists(0)" to test for the existence of an alternate
1002		file name.
1003							*buffer_exists()*
1004		Obsolete name: buffer_exists().
1005
1006buflisted({expr})					*buflisted()*
1007		The result is a Number, which is non-zero if a buffer called
1008		{expr} exists and is listed (has the 'buflisted' option set).
1009		The {expr} argument is used like with |bufexists()|.
1010
1011bufloaded({expr})					*bufloaded()*
1012		The result is a Number, which is non-zero if a buffer called
1013		{expr} exists and is loaded (shown in a window or hidden).
1014		The {expr} argument is used like with |bufexists()|.
1015
1016bufname({expr})						*bufname()*
1017		The result is the name of a buffer, as it is displayed by the
1018		":ls" command.
1019		If {expr} is a Number, that buffer number's name is given.
1020		Number zero is the alternate buffer for the current window.
1021		If {expr} is a String, it is used as a |file-pattern| to match
1022		with the buffer names.  This is always done like 'magic' is
1023		set and 'cpoptions' is empty.  When there is more than one
1024		match an empty string is returned.
1025		"" or "%" can be used for the current buffer, "#" for the
1026		alternate buffer.
1027		A full match is preferred, otherwise a match at the start, end
1028		or middle of the buffer name is accepted.
1029		Listed buffers are found first.  If there is a single match
1030		with a listed buffer, that one is returned.  Next unlisted
1031		buffers are searched for.
1032		If the {expr} is a String, but you want to use it as a buffer
1033		number, force it to be a Number by adding zero to it: >
1034			:echo bufname("3" + 0)
1035<		If the buffer doesn't exist, or doesn't have a name, an empty
1036		string is returned. >
1037	bufname("#")		alternate buffer name
1038	bufname(3)		name of buffer 3
1039	bufname("%")		name of current buffer
1040	bufname("file2")	name of buffer where "file2" matches.
1041<							*buffer_name()*
1042		Obsolete name: buffer_name().
1043
1044							*bufnr()*
1045bufnr({expr})	The result is the number of a buffer, as it is displayed by
1046		the ":ls" command.  For the use of {expr}, see |bufname()|
1047		above.  If the buffer doesn't exist, -1 is returned.
1048		bufnr("$") is the last buffer: >
1049	:let last_buffer = bufnr("$")
1050<		The result is a Number, which is the highest buffer number
1051		of existing buffers.  Note that not all buffers with a smaller
1052		number necessarily exist, because ":bwipeout" may have removed
1053		them.  Use bufexists() to test for the existence of a buffer.
1054							*buffer_number()*
1055		Obsolete name: buffer_number().
1056							*last_buffer_nr()*
1057		Obsolete name for bufnr("$"): last_buffer_nr().
1058
1059bufwinnr({expr})					*bufwinnr()*
1060		The result is a Number, which is the number of the first
1061		window associated with buffer {expr}.  For the use of {expr},
1062		see |bufname()| above.  If buffer {expr} doesn't exist or
1063		there is no such window, -1 is returned.  Example: >
1064
1065	echo "A window containing buffer 1 is " . (bufwinnr(1))
1066
1067<		The number can be used with |CTRL-W_w| and ":wincmd w"
1068		|:wincmd|.
1069
1070
1071byte2line({byte})					*byte2line()*
1072		Return the line number that contains the character at byte
1073		count {byte} in the current buffer.  This includes the
1074		end-of-line character, depending on the 'fileformat' option
1075		for the current buffer.  The first character has byte count
1076		one.
1077		Also see |line2byte()|, |go| and |:goto|.
1078		{not available when compiled without the |+byte_offset|
1079		feature}
1080
1081byteidx({expr}, {nr})					*byteidx()*
1082		Return byte index of the {nr}'th character in the string
1083		{expr}.  Use zero for the first character, it returns zero.
1084		This function is only useful when there are multibyte
1085		characters, otherwise the returned value is equal to {nr}.
1086		Composing characters are counted as a separate character.
1087		Example : >
1088			echo matchstr(str, ".", byteidx(str, 3))
1089<		will display the fourth character.  Another way to do the
1090		same: >
1091			let s = strpart(str, byteidx(str, 3))
1092			echo strpart(s, 0, byteidx(s, 1))
1093<		If there are less than {nr} characters -1 is returned.
1094		If there are exactly {nr} characters the length of the string
1095		is returned.
1096
1097char2nr({expr})						*char2nr()*
1098		Return number value of the first char in {expr}.  Examples: >
1099			char2nr(" ")		returns 32
1100			char2nr("ABC")		returns 65
1101<		The current 'encoding' is used.  Example for "utf-8": >
1102			char2nr("�")		returns 225
1103			char2nr("�"[0])		returns 195
1104
1105cindent({lnum})						*cindent()*
1106		Get the amount of indent for line {lnum} according the C
1107		indenting rules, as with 'cindent'.
1108		The indent is counted in spaces, the value of 'tabstop' is
1109		relevant.  {lnum} is used just like in |getline()|.
1110		When {lnum} is invalid or Vim was not compiled the |+cindent|
1111		feature, -1 is returned.
1112
1113							*col()*
1114col({expr})	The result is a Number, which is the byte index of the column
1115		position given with {expr}.  The accepted positions are:
1116		    .	    the cursor position
1117		    $	    the end of the cursor line (the result is the
1118			    number of characters in the cursor line plus one)
1119		    'x	    position of mark x (if the mark is not set, 0 is
1120			    returned)
1121		For the screen column position use |virtcol()|.
1122		Note that only marks in the current file can be used.
1123		Examples: >
1124			col(".")		column of cursor
1125			col("$")		length of cursor line plus one
1126			col("'t")		column of mark t
1127			col("'" . markname)	column of mark markname
1128<		The first column is 1.  0 is returned for an error.
1129		For the cursor position, when 'virtualedit' is active, the
1130		column is one higher if the cursor is after the end of the
1131		line.  This can be used to obtain the column in Insert mode: >
1132			:imap <F2> <C-O>:let save_ve = &ve<CR>
1133				\<C-O>:set ve=all<CR>
1134				\<C-O>:echo col(".") . "\n" <Bar>
1135				\let &ve = save_ve<CR>
1136<
1137						*confirm()*
1138confirm({msg} [, {choices} [, {default} [, {type}]]])
1139		Confirm() offers the user a dialog, from which a choice can be
1140		made.  It returns the number of the choice.  For the first
1141		choice this is 1.
1142		Note: confirm() is only supported when compiled with dialog
1143		support, see |+dialog_con| and |+dialog_gui|.
1144		{msg} is displayed in a |dialog| with {choices} as the
1145		alternatives.  When {choices} is missing or empty, "&OK" is
1146		used (and translated).
1147		{msg} is a String, use '\n' to include a newline.  Only on
1148		some systems the string is wrapped when it doesn't fit.
1149		{choices} is a String, with the individual choices separated
1150		by '\n', e.g. >
1151			confirm("Save changes?", "&Yes\n&No\n&Cancel")
1152<		The letter after the '&' is the shortcut key for that choice.
1153		Thus you can type 'c' to select "Cancel".  The shortcut does
1154		not need to be the first letter: >
1155			confirm("file has been modified", "&Save\nSave &All")
1156<		For the console, the first letter of each choice is used as
1157		the default shortcut key.
1158		The optional {default} argument is the number of the choice
1159		that is made if the user hits <CR>.  Use 1 to make the first
1160		choice the default one.  Use 0 to not set a default.  If
1161		{default} is omitted, 1 is used.
1162		The optional {type} argument gives the type of dialog.  This
1163		is only used for the icon of the Win32 GUI.  It can be one of
1164		these values: "Error", "Question", "Info", "Warning" or
1165		"Generic".  Only the first character is relevant.  When {type}
1166		is omitted, "Generic" is used.
1167		If the user aborts the dialog by pressing <Esc>, CTRL-C,
1168		or another valid interrupt key, confirm() returns 0.
1169
1170		An example: >
1171   :let choice = confirm("What do you want?", "&Apples\n&Oranges\n&Bananas", 2)
1172   :if choice == 0
1173   :	echo "make up your mind!"
1174   :elseif choice == 3
1175   :	echo "tasteful"
1176   :else
1177   :	echo "I prefer bananas myself."
1178   :endif
1179<		In a GUI dialog, buttons are used.  The layout of the buttons
1180		depends on the 'v' flag in 'guioptions'.  If it is included,
1181		the buttons are always put vertically.  Otherwise,  confirm()
1182		tries to put the buttons in one horizontal line.  If they
1183		don't fit, a vertical layout is used anyway.  For some systems
1184		the horizontal layout is always used.
1185
1186							*cscope_connection()*
1187cscope_connection([{num} , {dbpath} [, {prepend}]])
1188		Checks for the existence of a |cscope| connection.  If no
1189		parameters are specified, then the function returns:
1190			0, if cscope was not available (not compiled in), or
1191			   if there are no cscope connections;
1192			1, if there is at least one cscope connection.
1193
1194		If parameters are specified, then the value of {num}
1195		determines how existence of a cscope connection is checked:
1196
1197		{num}	Description of existence check
1198		-----	------------------------------
1199		0	Same as no parameters (e.g., "cscope_connection()").
1200		1	Ignore {prepend}, and use partial string matches for
1201			{dbpath}.
1202		2	Ignore {prepend}, and use exact string matches for
1203			{dbpath}.
1204		3	Use {prepend}, use partial string matches for both
1205			{dbpath} and {prepend}.
1206		4	Use {prepend}, use exact string matches for both
1207			{dbpath} and {prepend}.
1208
1209		Note: All string comparisons are case sensitive!
1210
1211		Examples.  Suppose we had the following (from ":cs show"): >
1212
1213  # pid    database name			prepend path
1214  0 27664  cscope.out				/usr/local
1215<
1216		Invocation					Return Val ~
1217		----------					---------- >
1218		cscope_connection()					1
1219		cscope_connection(1, "out")				1
1220		cscope_connection(2, "out")				0
1221		cscope_connection(3, "out")				0
1222		cscope_connection(3, "out", "local")			1
1223		cscope_connection(4, "out")				0
1224		cscope_connection(4, "out", "local")			0
1225		cscope_connection(4, "cscope.out", "/usr/local")	1
1226<
1227cursor({lnum}, {col})					*cursor()*
1228		Positions the cursor at the column {col} in the line {lnum}.
1229		Does not change the jumplist.
1230		If {lnum} is greater than the number of lines in the buffer,
1231		the cursor will be positioned at the last line in the buffer.
1232		If {lnum} is zero, the cursor will stay in the current line.
1233		If {col} is greater than the number of characters in the line,
1234		the cursor will be positioned at the last character in the
1235		line.
1236		If {col} is zero, the cursor will stay in the current column.
1237
1238							*delete()*
1239delete({fname})	Deletes the file by the name {fname}.  The result is a Number,
1240		which is 0 if the file was deleted successfully, and non-zero
1241		when the deletion failed.
1242
1243							*did_filetype()*
1244did_filetype()	Returns non-zero when autocommands are being executed and the
1245		FileType event has been triggered at least once.  Can be used
1246		to avoid triggering the FileType event again in the scripts
1247		that detect the file type. |FileType|
1248		When editing another file, the counter is reset, thus this
1249		really checks if the FileType event has been triggered for the
1250		current buffer.  This allows an autocommand that starts
1251		editing another buffer to set 'filetype' and load a syntax
1252		file.
1253
1254escape({string}, {chars})				*escape()*
1255		Escape the characters in {chars} that occur in {string} with a
1256		backslash.  Example: >
1257			:echo escape('c:\program files\vim', ' \')
1258<		results in: >
1259			c:\\program\ files\\vim
1260<
1261eventhandler()						*eventhandler()*
1262		Returns 1 when inside an event handler.  That is that Vim got
1263		interrupted while waiting for the user to type a character,
1264		e.g., when dropping a file on Vim.  This means interactive
1265		commands cannot be used.  Otherwise zero is returned.
1266
1267executable({expr})					*executable()*
1268		This function checks if an executable with the name {expr}
1269		exists.  {expr} must be the name of the program without any
1270		arguments.
1271		executable() uses the value of $PATH and/or the normal
1272		searchpath for programs.		*PATHEXT*
1273		On MS-DOS and MS-Windows the ".exe", ".bat", etc. can
1274		optionally be included.  Then the extensions in $PATHEXT are
1275		tried.  Thus if "foo.exe" does not exist, "foo.exe.bat" can be
1276		found.  If $PATHEXT is not set then ".exe;.com;.bat;.cmd" is
1277		used.  A dot by itself can be used in $PATHEXT to try using
1278		the name without an extension.  When 'shell' looks like a
1279		Unix shell, then the name is also tried without adding an
1280		extension.
1281		On MS-DOS and MS-Windows it only checks if the file exists and
1282		is not a directory, not if it's really executable.
1283		The result is a Number:
1284			1	exists
1285			0	does not exist
1286			-1	not implemented on this system
1287
1288							*exists()*
1289exists({expr})	The result is a Number, which is non-zero if {expr} is
1290		defined, zero otherwise.  The {expr} argument is a string,
1291		which contains one of these:
1292			&option-name	Vim option (only checks if it exists,
1293					not if it really works)
1294			+option-name	Vim option that works.
1295			$ENVNAME	environment variable (could also be
1296					done by comparing with an empty
1297					string)
1298			*funcname	built-in function (see |functions|)
1299					or user defined function (see
1300					|user-functions|).
1301			varname		internal variable (see
1302					|internal-variables|).  Does not work
1303					for |curly-braces-names|.
1304			:cmdname	Ex command: built-in command, user
1305					command or command modifier |:command|.
1306					Returns:
1307					1  for match with start of a command
1308					2  full match with a command
1309					3  matches several user commands
1310					To check for a supported command
1311					always check the return value to be 2.
1312			#event		autocommand defined for this event
1313			#event#pattern	autocommand defined for this event and
1314					pattern (the pattern is taken
1315					literally and compared to the
1316					autocommand patterns character by
1317					character)
1318		For checking for a supported feature use |has()|.
1319
1320		Examples: >
1321			exists("&shortname")
1322			exists("$HOSTNAME")
1323			exists("*strftime")
1324			exists("*s:MyFunc")
1325			exists("bufcount")
1326			exists(":Make")
1327			exists("#CursorHold");
1328			exists("#BufReadPre#*.gz")
1329<		There must be no space between the symbol (&/$/*/#) and the
1330		name.
1331		Note that the argument must be a string, not the name of the
1332		variable itself!  For example: >
1333			exists(bufcount)
1334<		This doesn't check for existence of the "bufcount" variable,
1335		but gets the contents of "bufcount", and checks if that
1336		exists.
1337
1338expand({expr} [, {flag}])				*expand()*
1339		Expand wildcards and the following special keywords in {expr}.
1340		The result is a String.
1341
1342		When there are several matches, they are separated by <NL>
1343		characters.  [Note: in version 5.0 a space was used, which
1344		caused problems when a file name contains a space]
1345
1346		If the expansion fails, the result is an empty string.  A name
1347		for a non-existing file is not included.
1348
1349		When {expr} starts with '%', '#' or '<', the expansion is done
1350		like for the |cmdline-special| variables with their associated
1351		modifiers.  Here is a short overview:
1352
1353			%		current file name
1354			#		alternate file name
1355			#n		alternate file name n
1356			<cfile>		file name under the cursor
1357			<afile>		autocmd file name
1358			<abuf>		autocmd buffer number (as a String!)
1359			<amatch>	autocmd matched name
1360			<sfile>		sourced script file name
1361			<cword>		word under the cursor
1362			<cWORD>		WORD under the cursor
1363			<client>	the {clientid} of the last received
1364					message |server2client()|
1365		Modifiers:
1366			:p		expand to full path
1367			:h		head (last path component removed)
1368			:t		tail (last path component only)
1369			:r		root (one extension removed)
1370			:e		extension only
1371
1372		Example: >
1373			:let &tags = expand("%:p:h") . "/tags"
1374<		Note that when expanding a string that starts with '%', '#' or
1375		'<', any following text is ignored.  This does NOT work: >
1376			:let doesntwork = expand("%:h.bak")
1377<		Use this: >
1378			:let doeswork = expand("%:h") . ".bak"
1379<		Also note that expanding "<cfile>" and others only returns the
1380		referenced file name without further expansion.  If "<cfile>"
1381		is "~/.cshrc", you need to do another expand() to have the
1382		"~/" expanded into the path of the home directory: >
1383			:echo expand(expand("<cfile>"))
1384<
1385		There cannot be white space between the variables and the
1386		following modifier.  The |fnamemodify()| function can be used
1387		to modify normal file names.
1388
1389		When using '%' or '#', and the current or alternate file name
1390		is not defined, an empty string is used.  Using "%:p" in a
1391		buffer with no name, results in the current directory, with a
1392		'/' added.
1393
1394		When {expr} does not start with '%', '#' or '<', it is
1395		expanded like a file name is expanded on the command line.
1396		'suffixes' and 'wildignore' are used, unless the optional
1397		{flag} argument is given and it is non-zero.  Names for
1398		non-existing files are included.
1399
1400		Expand() can also be used to expand variables and environment
1401		variables that are only known in a shell.  But this can be
1402		slow, because a shell must be started.  See |expr-env-expand|.
1403		The expanded variable is still handled like a list of file
1404		names.  When an environment variable cannot be expanded, it is
1405		left unchanged.  Thus ":echo expand('$FOOBAR')" results in
1406		"$FOOBAR".
1407
1408		See |glob()| for finding existing files.  See |system()| for
1409		getting the raw output of an external command.
1410
1411filereadable({file})					*filereadable()*
1412		The result is a Number, which is TRUE when a file with the
1413		name {file} exists, and can be read.  If {file} doesn't exist,
1414		or is a directory, the result is FALSE.  {file} is any
1415		expression, which is used as a String.
1416							*file_readable()*
1417		Obsolete name: file_readable().
1418
1419finddir({name}[, {path}[, {count}]])				*finddir()*
1420		Find directory {name} in {path}.
1421		If {path} is omitted or empty then 'path' is used.
1422		If the optional {count} is given, find {count}'s occurrence of
1423		{name} in {path}.
1424		This is quite similar to the ex-command |:find|.
1425		When the found directory is below the current directory a
1426		relative path is returned.  Otherwise a full path is returned.
1427		Example: >
1428			:echo findfile("tags.vim", ".;")
1429<		Searches from the current directory upwards until it finds
1430		the file "tags.vim".
1431		{only available when compiled with the +file_in_path feature}
1432
1433findfile({name}[, {path}[, {count}]])				*findfile()*
1434		Just like |finddir()|, but find a file instead of a directory.
1435
1436filewritable({file})					*filewritable()*
1437		The result is a Number, which is 1 when a file with the
1438		name {file} exists, and can be written.  If {file} doesn't
1439		exist, or is not writable, the result is 0.  If (file) is a
1440		directory, and we can write to it, the result is 2.
1441
1442fnamemodify({fname}, {mods})				*fnamemodify()*
1443		Modify file name {fname} according to {mods}.  {mods} is a
1444		string of characters like it is used for file names on the
1445		command line.  See |filename-modifiers|.
1446		Example: >
1447			:echo fnamemodify("main.c", ":p:h")
1448<		results in: >
1449			/home/mool/vim/vim/src
1450<		Note: Environment variables and "~" don't work in {fname}, use
1451		|expand()| first then.
1452
1453foldclosed({lnum})					*foldclosed()*
1454		The result is a Number.  If the line {lnum} is in a closed
1455		fold, the result is the number of the first line in that fold.
1456		If the line {lnum} is not in a closed fold, -1 is returned.
1457
1458foldclosedend({lnum})					*foldclosedend()*
1459		The result is a Number.  If the line {lnum} is in a closed
1460		fold, the result is the number of the last line in that fold.
1461		If the line {lnum} is not in a closed fold, -1 is returned.
1462
1463foldlevel({lnum})					*foldlevel()*
1464		The result is a Number, which is the foldlevel of line {lnum}
1465		in the current buffer.  For nested folds the deepest level is
1466		returned.  If there is no fold at line {lnum}, zero is
1467		returned.  It doesn't matter if the folds are open or closed.
1468		When used while updating folds (from 'foldexpr') -1 is
1469		returned for lines where folds are still to be updated and the
1470		foldlevel is unknown.  As a special case the level of the
1471		previous line is usually available.
1472
1473							*foldtext()*
1474foldtext()	Returns a String, to be displayed for a closed fold.  This is
1475		the default function used for the 'foldtext' option and should
1476		only be called from evaluating 'foldtext'.  It uses the
1477		|v:foldstart|, |v:foldend| and |v:folddashes| variables.
1478		The returned string looks like this: >
1479			+-- 45 lines: abcdef
1480<		The number of dashes depends on the foldlevel.  The "45" is
1481		the number of lines in the fold.  "abcdef" is the text in the
1482		first non-blank line of the fold.  Leading white space, "//"
1483		or "/*" and the text from the 'foldmarker' and 'commentstring'
1484		options is removed.
1485		{not available when compiled without the |+folding| feature}
1486
1487							*foreground()*
1488foreground()	Move the Vim window to the foreground.  Useful when sent from
1489		a client to a Vim server. |remote_send()|
1490		On Win32 systems this might not work, the OS does not always
1491		allow a window to bring itself to the foreground.  Use
1492		|remote_foreground()| instead.
1493		{only in the Win32, Athena, Motif and GTK GUI versions and the
1494		Win32 console version}
1495
1496getchar([expr])						*getchar()*
1497		Get a single character from the user.  If it is an 8-bit
1498		character, the result is a number.  Otherwise a String is
1499		returned with the encoded character.  For a special key it's a
1500		sequence of bytes starting with 0x80 (decimal: 128).
1501		If [expr] is omitted, wait until a character is available.
1502		If [expr] is 0, only get a character when one is available.
1503		If [expr] is 1, only check if a character is available, it is
1504				not consumed.  If a normal character is
1505				available, it is returned, otherwise a
1506				non-zero value is returned.
1507		If a normal character available, it is returned as a Number.
1508		Use nr2char() to convert it to a String.
1509		The returned value is zero if no character is available.
1510		The returned value is a string of characters for special keys
1511		and when a modifier (shift, control, alt) was used.
1512		There is no prompt, you will somehow have to make clear to the
1513		user that a character has to be typed.
1514		There is no mapping for the character.
1515		Key codes are replaced, thus when the user presses the <Del>
1516		key you get the code for the <Del> key, not the raw character
1517		sequence.  Examples: >
1518			getchar() == "\<Del>"
1519			getchar() == "\<S-Left>"
1520<		This example redefines "f" to ignore case: >
1521			:nmap f :call FindChar()<CR>
1522			:function FindChar()
1523			:  let c = nr2char(getchar())
1524			:  while col('.') < col('$') - 1
1525			:    normal l
1526			:    if getline('.')[col('.') - 1] ==? c
1527			:      break
1528			:    endif
1529			:  endwhile
1530			:endfunction
1531
1532getcharmod()						*getcharmod()*
1533		The result is a Number which is the state of the modifiers for
1534		the last obtained character with getchar() or in another way.
1535		These values are added together:
1536			2	shift
1537			4	control
1538			8	alt (meta)
1539			16	mouse double click
1540			32	mouse triple click
1541			64	mouse quadruple click
1542			128	Macintosh only: command
1543		Only the modifiers that have not been included in the
1544		character itself are obtained.  Thus Shift-a results in "A"
1545		with no modifier.
1546
1547getbufvar({expr}, {varname})				*getbufvar()*
1548		The result is the value of option or local buffer variable
1549		{varname} in buffer {expr}.  Note that the name without "b:"
1550		must be used.
1551		This also works for a global or local window option, but it
1552		doesn't work for a global or local window variable.
1553		For the use of {expr}, see |bufname()| above.
1554		When the buffer or variable doesn't exist an empty string is
1555		returned, there is no error message.
1556		Examples: >
1557			:let bufmodified = getbufvar(1, "&mod")
1558			:echo "todo myvar = " . getbufvar("todo", "myvar")
1559<
1560getcmdline()						*getcmdline()*
1561		Return the current command-line.  Only works when the command
1562		line is being edited, thus requires use of |c_CTRL-\_e| or
1563		|c_CTRL-R_=|.
1564		Example: >
1565			:cmap <F7> <C-\>eescape(getcmdline(), ' \')<CR>
1566<		Also see |getcmdpos()| and |setcmdpos()|.
1567
1568getcmdpos({pos})					*getcmdpos()*
1569		Return the position of the cursor in the command line as a
1570		byte count.  The first column is 1.
1571		Only works when editing the command line, thus requires use of
1572		|c_CTRL-\_e| or |c_CTRL-R_=|.  Returns 0 otherwise.
1573		Also see |setcmdpos()| and |getcmdline()|.
1574
1575							*getcwd()*
1576getcwd()	The result is a String, which is the name of the current
1577		working directory.
1578
1579getfsize({fname})					*getfsize()*
1580		The result is a Number, which is the size in bytes of the
1581		given file {fname}.
1582		If {fname} is a directory, 0 is returned.
1583		If the file {fname} can't be found, -1 is returned.
1584
1585getfperm({fname})					*getfperm()*
1586		The result is a String, which is the read, write, and execute
1587		permissions of the given file {fname}.
1588		If {fname} does not exist or its directory cannot be read, an
1589		empty string is returned.
1590		The result is of the form "rwxrwxrwx", where each group of
1591		"rwx" flags represent, in turn, the permissions of the owner
1592		of the file, the group the file belongs to, and other users.
1593		If a user does not have a given permission the flag for this
1594		is replaced with the string "-".  Example: >
1595			:echo getfperm("/etc/passwd")
1596<		This will hopefully (from a security point of view) display
1597		the string "rw-r--r--" or even "rw-------".
1598
1599getftime({fname})					*getftime()*
1600		The result is a Number, which is the last modification time of
1601		the given file {fname}.  The value is measured as seconds
1602		since 1st Jan 1970, and may be passed to strftime().  See also
1603		|localtime()| and |strftime()|.
1604		If the file {fname} can't be found -1 is returned.
1605
1606getftype({fname})					*getftype()*
1607		The result is a String, which is a description of the kind of
1608		file of the given file {fname}.
1609		If {fname} does not exist an empty string is returned.
1610		Here is a table over different kinds of files and their
1611		results:
1612			Normal file		"file"
1613			Directory		"dir"
1614			Symbolic link		"link"
1615			Block device		"bdev"
1616			Character device	"cdev"
1617			Socket			"socket"
1618			FIFO			"fifo"
1619			All other		"other"
1620		Example: >
1621			getftype("/home")
1622<		Note that a type such as "link" will only be returned on
1623		systems that support it.  On some systems only "dir" and
1624		"file" are returned.
1625
1626							*getline()*
1627getline({lnum}) The result is a String, which is line {lnum} from the current
1628		buffer.  Example: >
1629			getline(1)
1630<		When {lnum} is a String that doesn't start with a
1631		digit, line() is called to translate the String into a Number.
1632		To get the line under the cursor: >
1633			getline(".")
1634<		When {lnum} is smaller than 1 or bigger than the number of
1635		lines in the buffer, an empty string is returned.
1636
1637getreg([{regname}])					*getreg()*
1638		The result is a String, which is the contents of register
1639		{regname}. Example: >
1640			:let cliptext = getreg('*')
1641<		getreg('=') returns the last evaluated value of the expression
1642		register. (For use in maps).
1643		If {regname} is not specified, |v:register| is used.
1644
1645getregtype([{regname}])					*getregtype()*
1646		The result is a String, which is type of register {regname}.
1647		The value will be one of:
1648		    "v"			for |characterwise| text
1649		    "V"			for |linewise| text
1650		    "<CTRL-V>{width}"	for |blockwise-visual| text
1651		    0			for an empty or unknown register
1652		<CTRL-V> is one character with value 0x16.
1653		If {regname} is not specified, |v:register| is used.
1654
1655							*getwinposx()*
1656getwinposx()	The result is a Number, which is the X coordinate in pixels of
1657		the left hand side of the GUI Vim window.  The result will be
1658		-1 if the information is not available.
1659
1660							*getwinposy()*
1661getwinposy()	The result is a Number, which is the Y coordinate in pixels of
1662		the top of the GUI Vim window.  The result will be -1 if the
1663		information is not available.
1664
1665getwinvar({nr}, {varname})				*getwinvar()*
1666		The result is the value of option or local window variable
1667		{varname} in window {nr}.
1668		This also works for a global or local buffer option, but it
1669		doesn't work for a global or local buffer variable.
1670		Note that the name without "w:" must be used.
1671		Examples: >
1672			:let list_is_on = getwinvar(2, '&list')
1673			:echo "myvar = " . getwinvar(1, 'myvar')
1674<
1675							*glob()*
1676glob({expr})	Expand the file wildcards in {expr}.  The result is a String.
1677		When there are several matches, they are separated by <NL>
1678		characters.
1679		If the expansion fails, the result is an empty string.
1680		A name for a non-existing file is not included.
1681
1682		For most systems backticks can be used to get files names from
1683		any external command.  Example: >
1684			:let tagfiles = glob("`find . -name tags -print`")
1685			:let &tags = substitute(tagfiles, "\n", ",", "g")
1686<		The result of the program inside the backticks should be one
1687		item per line.  Spaces inside an item are allowed.
1688
1689		See |expand()| for expanding special Vim variables.  See
1690		|system()| for getting the raw output of an external command.
1691
1692globpath({path}, {expr})				*globpath()*
1693		Perform glob() on all directories in {path} and concatenate
1694		the results.  Example: >
1695			:echo globpath(&rtp, "syntax/c.vim")
1696<		{path} is a comma-separated list of directory names.  Each
1697		directory name is prepended to {expr} and expanded like with
1698		glob().  A path separator is inserted when needed.
1699		To add a comma inside a directory name escape it with a
1700		backslash.  Note that on MS-Windows a directory may have a
1701		trailing backslash, remove it if you put a comma after it.
1702		If the expansion fails for one of the directories, there is no
1703		error message.
1704		The 'wildignore' option applies: Names matching one of the
1705		patterns in 'wildignore' will be skipped.
1706
1707							*has()*
1708has({feature})	The result is a Number, which is 1 if the feature {feature} is
1709		supported, zero otherwise.  The {feature} argument is a
1710		string.  See |feature-list| below.
1711		Also see |exists()|.
1712
1713hasmapto({what} [, {mode}])				*hasmapto()*
1714		The result is a Number, which is 1 if there is a mapping that
1715		contains {what} in somewhere in the rhs (what it is mapped to)
1716		and this mapping exists in one of the modes indicated by
1717		{mode}.
1718		Both the global mappings and the mappings local to the current
1719		buffer are checked for a match.
1720		If no matching mapping is found 0 is returned.
1721		The following characters are recognized in {mode}:
1722			n	Normal mode
1723			v	Visual mode
1724			o	Operator-pending mode
1725			i	Insert mode
1726			l	Language-Argument ("r", "f", "t", etc.)
1727			c	Command-line mode
1728		When {mode} is omitted, "nvo" is used.
1729
1730		This function is useful to check if a mapping already exists
1731		to a function in a Vim script.  Example: >
1732			:if !hasmapto('\ABCdoit')
1733			:   map <Leader>d \ABCdoit
1734			:endif
1735<		This installs the mapping to "\ABCdoit" only if there isn't
1736		already a mapping to "\ABCdoit".
1737
1738histadd({history}, {item})				*histadd()*
1739		Add the String {item} to the history {history} which can be
1740		one of:					*hist-names*
1741			"cmd"	 or ":"	  command line history
1742			"search" or "/"   search pattern history
1743			"expr"   or "="   typed expression history
1744			"input"  or "@"	  input line history
1745		If {item} does already exist in the history, it will be
1746		shifted to become the newest entry.
1747		The result is a Number: 1 if the operation was successful,
1748		otherwise 0 is returned.
1749
1750		Example: >
1751			:call histadd("input", strftime("%Y %b %d"))
1752			:let date=input("Enter date: ")
1753<		This function is not available in the |sandbox|.
1754
1755histdel({history} [, {item}])				*histdel()*
1756		Clear {history}, ie. delete all its entries.  See |hist-names|
1757		for the possible values of {history}.
1758
1759		If the parameter {item} is given as String, this is seen
1760		as regular expression.  All entries matching that expression
1761		will be removed from the history (if there are any).
1762		Upper/lowercase must match, unless "\c" is used |/\c|.
1763		If {item} is a Number, it will be interpreted as index, see
1764		|:history-indexing|.  The respective entry will be removed
1765		if it exists.
1766
1767		The result is a Number: 1 for a successful operation,
1768		otherwise 0 is returned.
1769
1770		Examples:
1771		Clear expression register history: >
1772			:call histdel("expr")
1773<
1774		Remove all entries starting with "*" from the search history: >
1775			:call histdel("/", '^\*')
1776<
1777		The following three are equivalent: >
1778			:call histdel("search", histnr("search"))
1779			:call histdel("search", -1)
1780			:call histdel("search", '^'.histget("search", -1).'$')
1781<
1782		To delete the last search pattern and use the last-but-one for
1783		the "n" command and 'hlsearch': >
1784			:call histdel("search", -1)
1785			:let @/ = histget("search", -1)
1786
1787histget({history} [, {index}])				*histget()*
1788		The result is a String, the entry with Number {index} from
1789		{history}.  See |hist-names| for the possible values of
1790		{history}, and |:history-indexing| for {index}.  If there is
1791		no such entry, an empty String is returned.  When {index} is
1792		omitted, the most recent item from the history is used.
1793
1794		Examples:
1795		Redo the second last search from history. >
1796			:execute '/' . histget("search", -2)
1797
1798<		Define an Ex command ":H {num}" that supports re-execution of
1799		the {num}th entry from the output of |:history|. >
1800			:command -nargs=1 H execute histget("cmd", 0+<args>)
1801<
1802histnr({history})					*histnr()*
1803		The result is the Number of the current entry in {history}.
1804		See |hist-names| for the possible values of {history}.
1805		If an error occurred, -1 is returned.
1806
1807		Example: >
1808			:let inp_index = histnr("expr")
1809<
1810hlexists({name})					*hlexists()*
1811		The result is a Number, which is non-zero if a highlight group
1812		called {name} exists.  This is when the group has been
1813		defined in some way.  Not necessarily when highlighting has
1814		been defined for it, it may also have been used for a syntax
1815		item.
1816							*highlight_exists()*
1817		Obsolete name: highlight_exists().
1818
1819							*hlID()*
1820hlID({name})	The result is a Number, which is the ID of the highlight group
1821		with name {name}.  When the highlight group doesn't exist,
1822		zero is returned.
1823		This can be used to retrieve information about the highlight
1824		group.  For example, to get the background color of the
1825		"Comment" group: >
1826	:echo synIDattr(synIDtrans(hlID("Comment")), "bg")
1827<							*highlightID()*
1828		Obsolete name: highlightID().
1829
1830hostname()						*hostname()*
1831		The result is a String, which is the name of the machine on
1832		which Vim is currently running. Machine names greater than
1833		256 characters long are truncated.
1834
1835iconv({expr}, {from}, {to})				*iconv()*
1836		The result is a String, which is the text {expr} converted
1837		from encoding {from} to encoding {to}.
1838		When the conversion fails an empty string is returned.
1839		The encoding names are whatever the iconv() library function
1840		can accept, see ":!man 3 iconv".
1841		Most conversions require Vim to be compiled with the |+iconv|
1842		feature.  Otherwise only UTF-8 to latin1 conversion and back
1843		can be done.
1844		This can be used to display messages with special characters,
1845		no matter what 'encoding' is set to.  Write the message in
1846		UTF-8 and use: >
1847			echo iconv(utf8_str, "utf-8", &enc)
1848<		Note that Vim uses UTF-8 for all Unicode encodings, conversion
1849		from/to UCS-2 is automatically changed to use UTF-8.  You
1850		cannot use UCS-2 in a string anyway, because of the NUL bytes.
1851		{only available when compiled with the +multi_byte feature}
1852
1853							*indent()*
1854indent({lnum})	The result is a Number, which is indent of line {lnum} in the
1855		current buffer.  The indent is counted in spaces, the value
1856		of 'tabstop' is relevant.  {lnum} is used just like in
1857		|getline()|.
1858		When {lnum} is invalid -1 is returned.
1859
1860input({prompt} [, {text}])				*input()*
1861		The result is a String, which is whatever the user typed on
1862		the command-line.  The parameter is either a prompt string, or
1863		a blank string (for no prompt).  A '\n' can be used in the
1864		prompt to start a new line.  The highlighting set with
1865		|:echohl| is used for the prompt.  The input is entered just
1866		like a command-line, with the same editing commands and
1867		mappings.  There is a separate history for lines typed for
1868		input().
1869		If the optional {text} is present, this is used for the
1870		default reply, as if the user typed this.
1871		NOTE: This must not be used in a startup file, for the
1872		versions that only run in GUI mode (e.g., the Win32 GUI).
1873		Note: When input() is called from within a mapping it will
1874		consume remaining characters from that mapping, because a
1875		mapping is handled like the characters were typed.
1876		Use |inputsave()| before input() and |inputrestore()|
1877		after input() to avoid that.  Another solution is to avoid
1878		that further characters follow in the mapping, e.g., by using
1879		|:execute| or |:normal|.
1880
1881		Example: >
1882			:if input("Coffee or beer? ") == "beer"
1883			:  echo "Cheers!"
1884			:endif
1885<		Example with default text: >
1886			:let color = input("Color? ", "white")
1887<		Example with a mapping: >
1888			:nmap \x :call GetFoo()<CR>:exe "/" . Foo<CR>
1889			:function GetFoo()
1890			:  call inputsave()
1891			:  let g:Foo = input("enter search pattern: ")
1892			:  call inputrestore()
1893			:endfunction
1894
1895inputdialog({prompt} [, {text} [, {cancelreturn}]])		*inputdialog()*
1896		Like input(), but when the GUI is running and text dialogs are
1897		supported, a dialog window pops up to input the text.
1898		Example: >
1899			:let n = inputdialog("value for shiftwidth", &sw)
1900			:if n != ""
1901			:  let &sw = n
1902			:endif
1903<		When the dialog is cancelled {cancelreturn} is returned.  When
1904		omitted an empty string is returned.
1905		Hitting <Enter> works like pressing the OK button.  Hitting
1906		<Esc> works like pressing the Cancel button.
1907
1908inputrestore()						*inputrestore()*
1909		Restore typeahead that was saved with a previous inputsave().
1910		Should be called the same number of times inputsave() is
1911		called.  Calling it more often is harmless though.
1912		Returns 1 when there is nothing to restore, 0 otherwise.
1913
1914inputsave()						*inputsave()*
1915		Preserve typeahead (also from mappings) and clear it, so that
1916		a following prompt gets input from the user.  Should be
1917		followed by a matching inputrestore() after the prompt.  Can
1918		be used several times, in which case there must be just as
1919		many inputrestore() calls.
1920		Returns 1 when out of memory, 0 otherwise.
1921
1922inputsecret({prompt} [, {text}])			*inputsecret()*
1923		This function acts much like the |input()| function with but
1924		two exceptions:
1925		a) the user's response will be displayed as a sequence of
1926		asterisks ("*") thereby keeping the entry secret, and
1927		b) the user's response will not be recorded on the input
1928		|history| stack.
1929		The result is a String, which is whatever the user actually
1930		typed on the command-line in response to the issued prompt.
1931
1932isdirectory({directory})				*isdirectory()*
1933		The result is a Number, which is non-zero when a directory
1934		with the name {directory} exists.  If {directory} doesn't
1935		exist, or isn't a directory, the result is FALSE.  {directory}
1936		is any expression, which is used as a String.
1937
1938						*libcall()* *E364* *E368*
1939libcall({libname}, {funcname}, {argument})
1940		Call function {funcname} in the run-time library {libname}
1941		with single argument {argument}.
1942		This is useful to call functions in a library that you
1943		especially made to be used with Vim.  Since only one argument
1944		is possible, calling standard library functions is rather
1945		limited.
1946		The result is the String returned by the function.  If the
1947		function returns NULL, this will appear as an empty string ""
1948		to Vim.
1949		If the function returns a number, use libcallnr()!
1950		If {argument} is a number, it is passed to the function as an
1951		int; if {argument} is a string, it is passed as a
1952		null-terminated string.
1953		This function will fail in |restricted-mode|.
1954
1955		libcall() allows you to write your own 'plug-in' extensions to
1956		Vim without having to recompile the program.  It is NOT a
1957		means to call system functions!  If you try to do so Vim will
1958		very probably crash.
1959
1960		For Win32, the functions you write must be placed in a DLL
1961		and use the normal C calling convention (NOT Pascal which is
1962		used in Windows System DLLs).  The function must take exactly
1963		one parameter, either a character pointer or a long integer,
1964		and must return a character pointer or NULL.  The character
1965		pointer returned must point to memory that will remain valid
1966		after the function has returned (e.g. in static data in the
1967		DLL).  If it points to allocated memory, that memory will
1968		leak away.  Using a static buffer in the function should work,
1969		it's then freed when the DLL is unloaded.
1970
1971		WARNING: If the function returns a non-valid pointer, Vim may
1972		crash!  This also happens if the function returns a number,
1973		because Vim thinks it's a pointer.
1974		For Win32 systems, {libname} should be the filename of the DLL
1975		without the ".DLL" suffix.  A full path is only required if
1976		the DLL is not in the usual places.
1977		For Unix: When compiling your own plugins, remember that the
1978		object code must be compiled as position-independent ('PIC').
1979		{only in Win32 on some Unix versions, when the |+libcall|
1980		feature is present}
1981		Examples: >
1982			:echo libcall("libc.so", "getenv", "HOME")
1983			:echo libcallnr("/usr/lib/libc.so", "getpid", "")
1984<
1985							*libcallnr()*
1986libcallnr({libname}, {funcname}, {argument})
1987		Just like libcall(), but used for a function that returns an
1988		int instead of a string.
1989		{only in Win32 on some Unix versions, when the |+libcall|
1990		feature is present}
1991		Example (not very useful...): >
1992			:call libcallnr("libc.so", "printf", "Hello World!\n")
1993			:call libcallnr("libc.so", "sleep", 10)
1994<
1995							*line()*
1996line({expr})	The result is a Number, which is the line number of the file
1997		position given with {expr}.  The accepted positions are:
1998		    .	    the cursor position
1999		    $	    the last line in the current buffer
2000		    'x	    position of mark x (if the mark is not set, 0 is
2001			    returned)
2002		Note that only marks in the current file can be used.
2003		Examples: >
2004			line(".")		line number of the cursor
2005			line("'t")		line number of mark t
2006			line("'" . marker)	line number of mark marker
2007<							*last-position-jump*
2008		This autocommand jumps to the last known position in a file
2009		just after opening it, if the '" mark is set: >
2010	:au BufReadPost * if line("'\"") > 0 && line("'\"") <= line("$") | exe "normal g'\"" | endif
2011
2012line2byte({lnum})					*line2byte()*
2013		Return the byte count from the start of the buffer for line
2014		{lnum}.  This includes the end-of-line character, depending on
2015		the 'fileformat' option for the current buffer.  The first
2016		line returns 1.
2017		This can also be used to get the byte count for the line just
2018		below the last line: >
2019			line2byte(line("$") + 1)
2020<		This is the file size plus one.
2021		When {lnum} is invalid, or the |+byte_offset| feature has been
2022		disabled at compile time, -1 is returned.
2023		Also see |byte2line()|, |go| and |:goto|.
2024
2025lispindent({lnum})					*lispindent()*
2026		Get the amount of indent for line {lnum} according the lisp
2027		indenting rules, as with 'lisp'.
2028		The indent is counted in spaces, the value of 'tabstop' is
2029		relevant.  {lnum} is used just like in |getline()|.
2030		When {lnum} is invalid or Vim was not compiled the
2031		|+lispindent| feature, -1 is returned.
2032
2033localtime()						*localtime()*
2034		Return the current time, measured as seconds since 1st Jan
2035		1970.  See also |strftime()| and |getftime()|.
2036
2037maparg({name}[, {mode}])				*maparg()*
2038		Return the rhs of mapping {name} in mode {mode}.  When there
2039		is no mapping for {name}, an empty String is returned.
2040		These characters can be used for {mode}:
2041			"n"	Normal
2042			"v"	Visual
2043			"o"	Operator-pending
2044			"i"	Insert
2045			"c"	Cmd-line
2046			"l"	langmap |language-mapping|
2047			""	Normal, Visual and Operator-pending
2048		When {mode} is omitted, the modes from "" are used.
2049		The {name} can have special key names, like in the ":map"
2050		command.  The returned String has special characters
2051		translated like in the output of the ":map" command listing.
2052		The mappings local to the current buffer are checked first,
2053		then the global mappings.
2054
2055mapcheck({name}[, {mode}])				*mapcheck()*
2056		Check if there is a mapping that matches with {name} in mode
2057		{mode}.  See |maparg()| for {mode} and special names in
2058		{name}.
2059		A match happens with a mapping that starts with {name} and
2060		with a mapping which is equal to the start of {name}.
2061
2062			matches mapping "a"     "ab"    "abc" ~
2063		   mapcheck("a")	yes	yes	 yes
2064		   mapcheck("abc")	yes	yes	 yes
2065		   mapcheck("ax")	yes	no	 no
2066		   mapcheck("b")	no	no	 no
2067
2068		The difference with maparg() is that mapcheck() finds a
2069		mapping that matches with {name}, while maparg() only finds a
2070		mapping for {name} exactly.
2071		When there is no mapping that starts with {name}, an empty
2072		String is returned.  If there is one, the rhs of that mapping
2073		is returned.  If there are several mappings that start with
2074		{name}, the rhs of one of them is returned.
2075		The mappings local to the current buffer are checked first,
2076		then the global mappings.
2077		This function can be used to check if a mapping can be added
2078		without being ambiguous.  Example: >
2079	:if mapcheck("_vv") == ""
2080	:   map _vv :set guifont=7x13<CR>
2081	:endif
2082<		This avoids adding the "_vv" mapping when there already is a
2083		mapping for "_v" or for "_vvv".
2084
2085match({expr}, {pat}[, {start}[, {count}]])			*match()*
2086		The result is a Number, which gives the index (byte offset) in
2087		{expr} where {pat} matches.
2088		A match at the first character returns zero.
2089		If there is no match -1 is returned.
2090		Example: >
2091			:echo match("testing", "ing")
2092<		results in "4".
2093		See |string-match| for how {pat} is used.
2094		When {count} is given use the {count}'th match.  When a match
2095		is found the search for the next one starts on character
2096		further.  Thus this example results in 1: >
2097			echo match("testing", "..", 0, 2)
2098<		If {start} is given, the search starts from index {start}.
2099		The result, however, is still the index counted from the
2100		first character. Example: >
2101			:echo match("testing", "ing", 2)
2102<		result is again "4". >
2103			:echo match("testing", "ing", 4)
2104<		result is again "4". >
2105			:echo match("testing", "t", 2)
2106<		result is "3".
2107		If {start} < 0, it will be set to 0.
2108		If {start} > strlen({expr}) -1 is returned.
2109		See |pattern| for the patterns that are accepted.
2110		The 'ignorecase' option is used to set the ignore-caseness of
2111		the pattern.  'smartcase' is NOT used.  The matching is always
2112		done like 'magic' is set and 'cpoptions' is empty.
2113
2114matchend({expr}, {pat}[, {start}[, {count}]])			*matchend()*
2115		Same as match(), but return the index of first character after
2116		the match.  Example: >
2117			:echo matchend("testing", "ing")
2118<		results in "7".
2119		The {start}, if given, has the same meaning as for match(). >
2120			:echo matchend("testing", "ing", 2)
2121<		results in "7". >
2122			:echo matchend("testing", "ing", 5)
2123<		result is "-1".
2124
2125matchstr({expr}, {pat}[, {start}[, {count}]])			*matchstr()*
2126		Same as match(), but return the matched string.  Example: >
2127			:echo matchstr("testing", "ing")
2128<		results in "ing".
2129		When there is no match "" is returned.
2130		The {start}, if given, has the same meaning as for match(). >
2131			:echo matchstr("testing", "ing", 2)
2132<		results in "ing". >
2133			:echo matchstr("testing", "ing", 5)
2134<		result is "".
2135
2136							*mode()*
2137mode()		Return a string that indicates the current mode:
2138			n	Normal
2139			v	Visual by character
2140			V	Visual by line
2141			CTRL-V	Visual blockwise
2142			s	Select by character
2143			S	Select by line
2144			CTRL-S	Select blockwise
2145			i	Insert
2146			R	Replace
2147			c	Command-line
2148			r	Hit-enter prompt
2149		This is useful in the 'statusline' option.  In most other
2150		places it always returns "c" or "n".
2151
2152nextnonblank({lnum})					*nextnonblank()*
2153		Return the line number of the first line at or below {lnum}
2154		that is not blank.  Example: >
2155			if getline(nextnonblank(1)) =~ "Java"
2156<		When {lnum} is invalid or there is no non-blank line at or
2157		below it, zero is returned.
2158		See also |prevnonblank()|.
2159
2160nr2char({expr})						*nr2char()*
2161		Return a string with a single character, which has the number
2162		value {expr}.  Examples: >
2163			nr2char(64)		returns "@"
2164			nr2char(32)		returns " "
2165<		The current 'encoding' is used.  Example for "utf-8": >
2166			nr2char(300)		returns I with bow character
2167<		Note that a NUL character in the file is specified with
2168		nr2char(10), because NULs are represented with newline
2169		characters.  nr2char(0) is a real NUL and terminates the
2170		string, thus isn't very useful.
2171
2172prevnonblank({lnum})					*prevnonblank()*
2173		Return the line number of the first line at or above {lnum}
2174		that is not blank.  Example: >
2175			let ind = indent(prevnonblank(v:lnum - 1))
2176<		When {lnum} is invalid or there is no non-blank line at or
2177		above it, zero is returned.
2178		Also see |nextnonblank()|.
2179
2180							*remote_expr()* *E449*
2181remote_expr({server}, {string} [, {idvar}])
2182		Send the {string} to {server}.  The string is sent as an
2183		expression and the result is returned after evaluation.
2184		If {idvar} is present, it is taken as the name of a
2185		variable and a {serverid} for later use with
2186		remote_read() is stored there.
2187		See also |clientserver| |RemoteReply|.
2188		This function is not available in the |sandbox|.
2189		{only available when compiled with the |+clientserver| feature}
2190		Note: Any errors will cause a local error message to be issued
2191		and the result will be the empty string.
2192		Examples: >
2193			:echo remote_expr("gvim", "2+2")
2194			:echo remote_expr("gvim1", "b:current_syntax")
2195<
2196
2197remote_foreground({server})				*remote_foreground()*
2198		Move the Vim server with the name {server} to the foreground.
2199		This works like: >
2200			remote_expr({server}, "foreground()")
2201<		Except that on Win32 systems the client does the work, to work
2202		around the problem that the OS doesn't always allow the server
2203		to bring itself to the foreground.
2204		This function is not available in the |sandbox|.
2205		{only in the Win32, Athena, Motif and GTK GUI versions and the
2206		Win32 console version}
2207
2208
2209remote_peek({serverid} [, {retvar}])		*remote_peek()*
2210		Returns a positive number if there are available strings
2211		from {serverid}.  Copies any reply string into the variable
2212		{retvar} if specified.  {retvar} must be a string with the
2213		name of a variable.
2214		Returns zero if none are available.
2215		Returns -1 if something is wrong.
2216		See also |clientserver|.
2217		This function is not available in the |sandbox|.
2218		{only available when compiled with the |+clientserver| feature}
2219		Examples: >
2220			:let repl = ""
2221			:echo "PEEK: ".remote_peek(id, "repl").": ".repl
2222
2223remote_read({serverid})				*remote_read()*
2224		Return the oldest available reply from {serverid} and consume
2225		it.  It blocks until a reply is available.
2226		See also |clientserver|.
2227		This function is not available in the |sandbox|.
2228		{only available when compiled with the |+clientserver| feature}
2229		Example: >
2230			:echo remote_read(id)
2231<
2232							*remote_send()* *E241*
2233remote_send({server}, {string} [, {idvar}])
2234		Send the {string} to {server}.  The string is sent as input
2235		keys and the function returns immediately.  At the Vim server
2236		the keys are not mapped |:map|.
2237		If {idvar} is present, it is taken as the name of a
2238		variable and a {serverid} for later use with
2239		remote_read() is stored there.
2240		See also |clientserver| |RemoteReply|.
2241		This function is not available in the |sandbox|.
2242		{only available when compiled with the |+clientserver| feature}
2243		Note: Any errors will be reported in the server and may mess
2244		up the display.
2245		Examples: >
2246		:echo remote_send("gvim", ":DropAndReply ".file, "serverid").
2247		 \ remote_read(serverid)
2248
2249		:autocmd NONE RemoteReply *
2250		 \ echo remote_read(expand("<amatch>"))
2251		:echo remote_send("gvim", ":sleep 10 | echo ".
2252		 \ 'server2client(expand("<client>"), "HELLO")<CR>')
2253
2254
2255rename({from}, {to})					*rename()*
2256		Rename the file by the name {from} to the name {to}.  This
2257		should also work to move files across file systems.  The
2258		result is a Number, which is 0 if the file was renamed
2259		successfully, and non-zero when the renaming failed.
2260		This function is not available in the |sandbox|.
2261
2262repeat({expr}, {count})					*repeat()*
2263		Repeat {expr} {count} times and return the concatenated
2264		result.  Example: >
2265			:let seperator = repeat('-', 80)
2266<		When {count} is zero or negative the result is empty.
2267
2268resolve({filename})					*resolve()* *E655*
2269		On MS-Windows, when {filename} is a shortcut (a .lnk file),
2270		returns the path the shortcut points to in a simplified form.
2271		On Unix, repeat resolving symbolic links in all path
2272		components of {filename} and return the simplified result.
2273		To cope with link cycles, resolving of symbolic links is
2274		stopped after 100 iterations.
2275		On other systems, return the simplified {filename}.
2276		The simplification step is done as by |simplify()|.
2277		resolve() keeps a leading path component specifying the
2278		current directory (provided the result is still a relative
2279		path name) and also keeps a trailing path separator.
2280
2281search({pattern} [, {flags}])				*search()*
2282		Search for regexp pattern {pattern}.  The search starts at the
2283		cursor position.
2284		{flags} is a String, which can contain these character flags:
2285		'b'	search backward instead of forward
2286		'n'	do Not move the cursor
2287		'w'	wrap around the end of the file
2288		'W'	don't wrap around the end of the file
2289		If neither 'w' or 'W' is given, the 'wrapscan' option applies.
2290
2291		When a match has been found its line number is returned.
2292		The cursor will be positioned at the match, unless the 'n'
2293		flag is used).
2294		If there is no match a 0 is returned and the cursor doesn't
2295		move.  No error message is given.
2296
2297		Example (goes over all files in the argument list): >
2298		    :let n = 1
2299		    :while n <= argc()	    " loop over all files in arglist
2300		    :  exe "argument " . n
2301		    :  " start at the last char in the file and wrap for the
2302		    :  " first search to find match at start of file
2303		    :  normal G$
2304		    :  let flags = "w"
2305		    :  while search("foo", flags) > 0
2306		    :    s/foo/bar/g
2307		    :	 let flags = "W"
2308		    :  endwhile
2309		    :  update		    " write the file if modified
2310		    :  let n = n + 1
2311		    :endwhile
2312<
2313							*searchpair()*
2314searchpair({start}, {middle}, {end} [, {flags} [, {skip}]])
2315		Search for the match of a nested start-end pair.  This can be
2316		used to find the "endif" that matches an "if", while other
2317		if/endif pairs in between are ignored.
2318		The search starts at the cursor.  If a match is found, the
2319		cursor is positioned at it and the line number is returned.
2320		If no match is found 0 or -1 is returned and the cursor
2321		doesn't move.  No error message is given.
2322
2323		{start}, {middle} and {end} are patterns, see |pattern|.  They
2324		must not contain \( \) pairs.  Use of \%( \) is allowed.  When
2325		{middle} is not empty, it is found when searching from either
2326		direction, but only when not in a nested start-end pair.  A
2327		typical use is: >
2328			searchpair('\<if\>', '\<else\>', '\<endif\>')
2329<		By leaving {middle} empty the "else" is skipped.
2330
2331		{flags} are used like with |search()|.  Additionally:
2332		'n'	do Not move the cursor
2333		'r'	Repeat until no more matches found; will find the
2334			outer pair
2335		'm'	return number of Matches instead of line number with
2336			the match; will only be > 1 when 'r' is used.
2337
2338		When a match for {start}, {middle} or {end} is found, the
2339		{skip} expression is evaluated with the cursor positioned on
2340		the start of the match.  It should return non-zero if this
2341		match is to be skipped.  E.g., because it is inside a comment
2342		or a string.
2343		When {skip} is omitted or empty, every match is accepted.
2344		When evaluating {skip} causes an error the search is aborted
2345		and -1 returned.
2346
2347		The value of 'ignorecase' is used.  'magic' is ignored, the
2348		patterns are used like it's on.
2349
2350		The search starts exactly at the cursor.  A match with
2351		{start}, {middle} or {end} at the next character, in the
2352		direction of searching, is the first one found.  Example: >
2353			if 1
2354			  if 2
2355			  endif 2
2356			endif 1
2357<		When starting at the "if 2", with the cursor on the "i", and
2358		searching forwards, the "endif 2" is found.  When starting on
2359		the character just before the "if 2", the "endif 1" will be
2360		found.  That's because the "if 2" will be found first, and
2361		then this is considered to be a nested if/endif from "if 2" to
2362		"endif 2".
2363		When searching backwards and {end} is more than one character,
2364		it may be useful to put "\zs" at the end of the pattern, so
2365		that when the cursor is inside a match with the end it finds
2366		the matching start.
2367
2368		Example, to find the "endif" command in a Vim script: >
2369
2370	:echo searchpair('\<if\>', '\<el\%[seif]\>', '\<en\%[dif]\>', 'W',
2371			\ 'getline(".") =~ "^\\s*\""')
2372
2373<		The cursor must be at or after the "if" for which a match is
2374		to be found.  Note that single-quote strings are used to avoid
2375		having to double the backslashes.  The skip expression only
2376		catches comments at the start of a line, not after a command.
2377		Also, a word "en" or "if" halfway a line is considered a
2378		match.
2379		Another example, to search for the matching "{" of a "}": >
2380
2381	:echo searchpair('{', '', '}', 'bW')
2382
2383<		This works when the cursor is at or before the "}" for which a
2384		match is to be found.  To reject matches that syntax
2385		highlighting recognized as strings: >
2386
2387	:echo searchpair('{', '', '}', 'bW',
2388	     \ 'synIDattr(synID(line("."), col("."), 0), "name") =~? "string"')
2389<
2390server2client( {clientid}, {string})			*server2client()*
2391		Send a reply string to {clientid}.  The most recent {clientid}
2392		that sent a string can be retrieved with expand("<client>").
2393		{only available when compiled with the |+clientserver| feature}
2394		Note:
2395		This id has to be stored before the next command can be
2396		received. Ie. before returning from the received command and
2397		before calling any commands that waits for input.
2398		See also |clientserver|.
2399		Example: >
2400			:echo server2client(expand("<client>"), "HELLO")
2401<
2402serverlist()					*serverlist()*
2403		Return a list of available server names, one per line.
2404		When there are no servers or the information is not available
2405		an empty string is returned.  See also |clientserver|.
2406		{only available when compiled with the |+clientserver| feature}
2407		Example: >
2408			:echo serverlist()
2409<
2410setbufvar({expr}, {varname}, {val})			*setbufvar()*
2411		Set option or local variable {varname} in buffer {expr} to
2412		{val}.
2413		This also works for a global or local window option, but it
2414		doesn't work for a global or local window variable.
2415		For a local window option the global value is unchanged.
2416		For the use of {expr}, see |bufname()| above.
2417		Note that the variable name without "b:" must be used.
2418		Examples: >
2419			:call setbufvar(1, "&mod", 1)
2420			:call setbufvar("todo", "myvar", "foobar")
2421<		This function is not available in the |sandbox|.
2422
2423setcmdpos({pos})					*setcmdpos()*
2424		Set the cursor position in the command line to byte position
2425		{pos}.  The first position is 1.
2426		Use |getcmdpos()| to obtain the current position.
2427		Only works while editing the command line, thus you must use
2428		|c_CTRL-\_e| or |c_CTRL-R_=|.  The position is set after the
2429		command line is set to the expression.
2430		When the number is too big the cursor is put at the end of the
2431		line.  A number smaller than one has undefined results.
2432		Returns 0 when successful, 1 when not editing the command
2433		line.
2434
2435setline({lnum}, {line})					*setline()*
2436		Set line {lnum} of the current buffer to {line}.  If this
2437		succeeds, 0 is returned.  If this fails (most likely because
2438		{lnum} is invalid) 1 is returned.  Example: >
2439			:call setline(5, strftime("%c"))
2440<		Note: The '[ and '] marks are not set.
2441
2442							*setreg()*
2443setreg({regname}, {value} [,{options}])
2444		Set the register {regname} to {value}.
2445		If {options} contains "a" or {regname} is upper case,
2446		then the value is appended.
2447		{options} can also contains a register type specification:
2448		    "c" or "v"	      |characterwise| mode
2449		    "l" or "V"	      |linewise| mode
2450		    "b" or "<CTRL-V>" |blockwise-visual| mode
2451		If a number immediately follows "b" or "<CTRL-V>" then this is
2452		used as the width of the selection - if it is not specified
2453		then the width of the block is set to the number of characters
2454		in the longest line (counting a <TAB> as 1 character).
2455
2456		If {options} contains no register settings, then the default
2457		is to use character mode unless {value} ends in a <NL>.
2458		Setting the '=' register is not possible.
2459		Returns zero for success, non-zero for failure.
2460
2461		Examples: >
2462			:call setreg(v:register, @*)
2463			:call setreg('*', @%, 'ac')
2464			:call setreg('a', "1\n2\n3", 'b5')
2465
2466<		This example shows using the functions to save and restore a
2467		register. >
2468			:let var_a = getreg('a')
2469			:let var_amode = getregtype('a')
2470			    ....
2471			:call setreg('a', var_a, var_amode)
2472
2473<		You can also change the type of a register by appending
2474		nothing: >
2475			:call setreg('a', '', 'al')
2476
2477setwinvar({nr}, {varname}, {val})			*setwinvar()*
2478		Set option or local variable {varname} in window {nr} to
2479		{val}.
2480		This also works for a global or local buffer option, but it
2481		doesn't work for a global or local buffer variable.
2482		For a local buffer option the global value is unchanged.
2483		Note that the variable name without "w:" must be used.
2484		Examples: >
2485			:call setwinvar(1, "&list", 0)
2486			:call setwinvar(2, "myvar", "foobar")
2487<		This function is not available in the |sandbox|.
2488
2489simplify({filename})					*simplify()*
2490		Simplify the file name as much as possible without changing
2491		the meaning.  Shortcuts (on MS-Windows) or symbolic links (on
2492		Unix) are not resolved.  If the first path component in
2493		{filename} designates the current directory, this will be
2494		valid for the result as well.  A trailing path separator is
2495		not removed either.
2496		Example: >
2497			simplify("./dir/.././/file/") == "./file/"
2498<		Note: The combination "dir/.." is only removed if "dir" is
2499		a searchable directory or does not exist.  On Unix, it is also
2500		removed when "dir" is a symbolic link within the same
2501		directory.  In order to resolve all the involved symbolic
2502		links before simplifying the path name, use |resolve()|.
2503
2504strftime({format} [, {time}])				*strftime()*
2505		The result is a String, which is a formatted date and time, as
2506		specified by the {format} string.  The given {time} is used,
2507		or the current time if no time is given.  The accepted
2508		{format} depends on your system, thus this is not portable!
2509		See the manual page of the C function strftime() for the
2510		format.  The maximum length of the result is 80 characters.
2511		See also |localtime()| and |getftime()|.
2512		The language can be changed with the |:language| command.
2513		Examples: >
2514		  :echo strftime("%c")		   Sun Apr 27 11:49:23 1997
2515		  :echo strftime("%Y %b %d %X")	   1997 Apr 27 11:53:25
2516		  :echo strftime("%y%m%d %T")	   970427 11:53:55
2517		  :echo strftime("%H:%M")	   11:55
2518		  :echo strftime("%c", getftime("file.c"))
2519						   Show mod time of file.c.
2520<
2521stridx({haystack}, {needle})				*stridx()*
2522		The result is a Number, which gives the index in {haystack} of
2523		the first occurrence of the String {needle} in the String
2524		{haystack}. The search is done case-sensitive. For advanced
2525		searches use |match()|.
2526		If the {needle} does not occur in {haystack} it returns -1.
2527		See also |strridx()|. Examples: >
2528		  :echo stridx("An Example", "Example")	     3
2529		  :echo stridx("Starting point", "Start")    0
2530		  :echo stridx("Starting point", "start")   -1
2531<
2532							*strlen()*
2533strlen({expr})	The result is a Number, which is the length of the String
2534		{expr} in bytes.  If you want to count the number of
2535		multi-byte characters use something like this: >
2536
2537			:let len = strlen(substitute(str, ".", "x", "g"))
2538
2539<		Composing characters are not counted.
2540
2541strpart({src}, {start}[, {len}])			*strpart()*
2542		The result is a String, which is part of {src}, starting from
2543		byte {start}, with the length {len}.
2544		When non-existing bytes are included, this doesn't result in
2545		an error, the bytes are simply omitted.
2546		If {len} is missing, the copy continues from {start} till the
2547		end of the {src}. >
2548			strpart("abcdefg", 3, 2)    == "de"
2549			strpart("abcdefg", -2, 4)   == "ab"
2550			strpart("abcdefg", 5, 4)    == "fg"
2551			strpart("abcdefg", 3)       == "defg"
2552<		Note: To get the first character, {start} must be 0.  For
2553		example, to get three bytes under and after the cursor: >
2554			strpart(getline(line(".")), col(".") - 1, 3)
2555<
2556strridx({haystack}, {needle})				*strridx()*
2557		The result is a Number, which gives the index in {haystack} of
2558		the last occurrence of the String {needle} in the String
2559		{haystack}. The search is done case-sensitive. For advanced
2560		searches use |match()|.
2561		If the {needle} does not occur in {haystack} it returns -1.
2562		If the {needle} is empty the length of {haystack} is returned.
2563		See also |stridx()|. Examples: >
2564		  :echo strridx("an angry armadillo", "an")	     3
2565<
2566strtrans({expr})					*strtrans()*
2567		The result is a String, which is {expr} with all unprintable
2568		characters translated into printable characters |'isprint'|.
2569		Like they are shown in a window.  Example: >
2570			echo strtrans(@a)
2571<		This displays a newline in register a as "^@" instead of
2572		starting a new line.
2573
2574submatch({nr})						*submatch()*
2575		Only for an expression in a |:substitute| command.  Returns
2576		the {nr}'th submatch of the matched text.  When {nr} is 0
2577		the whole matched text is returned.
2578		Example: >
2579			:s/\d\+/\=submatch(0) + 1/
2580<		This finds the first number in the line and adds one to it.
2581		A line break is included as a newline character.
2582
2583substitute({expr}, {pat}, {sub}, {flags})		*substitute()*
2584		The result is a String, which is a copy of {expr}, in which
2585		the first match of {pat} is replaced with {sub}.  This works
2586		like the ":substitute" command (without any flags).  But the
2587		matching with {pat} is always done like the 'magic' option is
2588		set and 'cpoptions' is empty (to make scripts portable).
2589		See |string-match| for how {pat} is used.
2590		And a "~" in {sub} is not replaced with the previous {sub}.
2591		Note that some codes in {sub} have a special meaning
2592		|sub-replace-special|.  For example, to replace something with
2593		"\n" (two characters), use "\\\\n" or '\\n'.
2594		When {pat} does not match in {expr}, {expr} is returned
2595		unmodified.
2596		When {flags} is "g", all matches of {pat} in {expr} are
2597		replaced.  Otherwise {flags} should be "".
2598		Example: >
2599			:let &path = substitute(&path, ",\\=[^,]*$", "", "")
2600<		This removes the last component of the 'path' option. >
2601			:echo substitute("testing", ".*", "\\U\\0", "")
2602<		results in "TESTING".
2603
2604synID({line}, {col}, {trans})				*synID()*
2605		The result is a Number, which is the syntax ID at the position
2606		{line} and {col} in the current window.
2607		The syntax ID can be used with |synIDattr()| and
2608		|synIDtrans()| to obtain syntax information about text.
2609		{col} is 1 for the leftmost column, {line} is 1 for the first
2610		line.
2611		When {trans} is non-zero, transparent items are reduced to the
2612		item that they reveal.  This is useful when wanting to know
2613		the effective color.  When {trans} is zero, the transparent
2614		item is returned.  This is useful when wanting to know which
2615		syntax item is effective (e.g. inside parens).
2616		Warning: This function can be very slow.  Best speed is
2617		obtained by going through the file in forward direction.
2618
2619		Example (echoes the name of the syntax item under the cursor): >
2620			:echo synIDattr(synID(line("."), col("."), 1), "name")
2621<
2622synIDattr({synID}, {what} [, {mode}])			*synIDattr()*
2623		The result is a String, which is the {what} attribute of
2624		syntax ID {synID}.  This can be used to obtain information
2625		about a syntax item.
2626		{mode} can be "gui", "cterm" or "term", to get the attributes
2627		for that mode.  When {mode} is omitted, or an invalid value is
2628		used, the attributes for the currently active highlighting are
2629		used (GUI, cterm or term).
2630		Use synIDtrans() to follow linked highlight groups.
2631		{what}		result
2632		"name"		the name of the syntax item
2633		"fg"		foreground color (GUI: color name used to set
2634				the color, cterm: color number as a string,
2635				term: empty string)
2636		"bg"		background color (like "fg")
2637		"fg#"		like "fg", but for the GUI and the GUI is
2638				running the name in "#RRGGBB" form
2639		"bg#"		like "fg#" for "bg"
2640		"bold"		"1" if bold
2641		"italic"	"1" if italic
2642		"reverse"	"1" if reverse
2643		"inverse"	"1" if inverse (= reverse)
2644		"underline"	"1" if underlined
2645
2646		Example (echoes the color of the syntax item under the
2647		cursor): >
2648	:echo synIDattr(synIDtrans(synID(line("."), col("."), 1)), "fg")
2649<
2650synIDtrans({synID})					*synIDtrans()*
2651		The result is a Number, which is the translated syntax ID of
2652		{synID}.  This is the syntax group ID of what is being used to
2653		highlight the character.  Highlight links given with
2654		":highlight link" are followed.
2655
2656system({expr} [, {input}])				*system()* *E677*
2657		Get the output of the shell command {expr}.
2658		When {input} is given, this string is written to a file and
2659		passed as stdin to the command.  The string is written as-is,
2660		you need to take care of using the correct line separators
2661		yourself.
2662		Note: newlines in {expr} may cause the command to fail.  The
2663		characters in 'shellquote' and 'shellxquote' may also cause
2664		trouble.
2665		This is not to be used for interactive commands.
2666		The result is a String.  Example: >
2667
2668			:let files = system("ls")
2669
2670<		To make the result more system-independent, the shell output
2671		is filtered to replace <CR> with <NL> for Macintosh, and
2672		<CR><NL> with <NL> for DOS-like systems.
2673		The command executed is constructed using several options:
2674	'shell' 'shellcmdflag' 'shellxquote' {expr} 'shellredir' {tmp} 'shellxquote'
2675		({tmp} is an automatically generated file name).
2676		For Unix and OS/2 braces are put around {expr} to allow for
2677		concatenated commands.
2678
2679		The resulting error code can be found in |v:shell_error|.
2680		This function will fail in |restricted-mode|.
2681		Unlike ":!cmd" there is no automatic check for changed files.
2682		Use |:checktime| to force a check.
2683
2684tempname()					*tempname()* *temp-file-name*
2685		The result is a String, which is the name of a file that
2686		doesn't exist.  It can be used for a temporary file.  The name
2687		is different for at least 26 consecutive calls.  Example: >
2688			:let tmpfile = tempname()
2689			:exe "redir > " . tmpfile
2690<		For Unix, the file will be in a private directory (only
2691		accessible by the current user) to avoid security problems
2692		(e.g., a symlink attack or other people reading your file).
2693		When Vim exits the directory and all files in it are deleted.
2694		For MS-Windows forward slashes are used when the 'shellslash'
2695		option is set or when 'shellcmdflag' starts with '-'.
2696
2697tolower({expr})						*tolower()*
2698		The result is a copy of the String given, with all uppercase
2699		characters turned into lowercase (just like applying |gu| to
2700		the string).
2701
2702toupper({expr})						*toupper()*
2703		The result is a copy of the String given, with all lowercase
2704		characters turned into uppercase (just like applying |gU| to
2705		the string).
2706
2707tr({src}, {fromstr}, {tostr})				*tr()*
2708		The result is a copy of the {src} string with all characters
2709		which appear in {fromstr} replaced by the character in that
2710		position in the {tostr} string.  Thus the first character in
2711		{fromstr} is translated into the first character in {tostr}
2712		and so on.  Exactly like the unix "tr" command.
2713		This code also deals with multibyte characters properly.
2714
2715		Examples: >
2716			echo tr("hello there", "ht", "HT")
2717<		returns "Hello THere" >
2718			echo tr("<blob>", "<>", "{}")
2719<		returns "{blob}"
2720
2721type({expr})						*type()*
2722		The result is a Number:
2723			0 if {expr} has the type Number
2724			1 if {expr} has the type String
2725
2726virtcol({expr})						*virtcol()*
2727		The result is a Number, which is the screen column of the file
2728		position given with {expr}.  That is, the last screen position
2729		occupied by the character at that position, when the screen
2730		would be of unlimited width.  When there is a <Tab> at the
2731		position, the returned Number will be the column at the end of
2732		the <Tab>.  For example, for a <Tab> in column 1, with 'ts'
2733		set to 8, it returns 8.
2734		For the byte position use |col()|.
2735		When Virtual editing is active in the current mode, a position
2736		beyond the end of the line can be returned. |'virtualedit'|
2737		The accepted positions are:
2738		    .	    the cursor position
2739		    $	    the end of the cursor line (the result is the
2740			    number of displayed characters in the cursor line
2741			    plus one)
2742		    'x	    position of mark x (if the mark is not set, 0 is
2743			    returned)
2744		Note that only marks in the current file can be used.
2745		Examples: >
2746  virtcol(".")	   with text "foo^Lbar", with cursor on the "^L", returns 5
2747  virtcol("$")	   with text "foo^Lbar", returns 9
2748  virtcol("'t")    with text "    there", with 't at 'h', returns 6
2749<		The first column is 1.  0 is returned for an error.
2750
2751visualmode([expr])						*visualmode()*
2752		The result is a String, which describes the last Visual mode
2753		used.  Initially it returns an empty string, but once Visual
2754		mode has been used, it returns "v", "V", or "<CTRL-V>" (a
2755		single CTRL-V character) for character-wise, line-wise, or
2756		block-wise Visual mode respectively.
2757		Example: >
2758			:exe "normal " . visualmode()
2759<		This enters the same Visual mode as before.  It is also useful
2760		in scripts if you wish to act differently depending on the
2761		Visual mode that was used.
2762
2763		If an expression is supplied that results in a non-zero number
2764		or a non-empty string, then the Visual mode will be cleared
2765		and the old value is returned.  Note that " " and "0" are also
2766		non-empty strings, thus cause the mode to be cleared.
2767
2768							*winbufnr()*
2769winbufnr({nr})	The result is a Number, which is the number of the buffer
2770		associated with window {nr}. When {nr} is zero, the number of
2771		the buffer in the current window is returned.  When window
2772		{nr} doesn't exist, -1 is returned.
2773		Example: >
2774  :echo "The file in the current window is " . bufname(winbufnr(0))
2775<
2776							*wincol()*
2777wincol()	The result is a Number, which is the virtual column of the
2778		cursor in the window.  This is counting screen cells from the
2779		left side of the window.  The leftmost column is one.
2780
2781winheight({nr})						*winheight()*
2782		The result is a Number, which is the height of window {nr}.
2783		When {nr} is zero, the height of the current window is
2784		returned.  When window {nr} doesn't exist, -1 is returned.
2785		An existing window always has a height of zero or more.
2786		Examples: >
2787  :echo "The current window has " . winheight(0) . " lines."
2788<
2789							*winline()*
2790winline()	The result is a Number, which is the screen line of the cursor
2791		in the window.  This is counting screen lines from the top of
2792		the window.  The first line is one.
2793
2794							*winnr()*
2795winnr([{arg}])	The result is a Number, which is the number of the current
2796		window.  The top window has number 1.
2797		When the optional argument is "$", the number of the
2798		last window is returnd (the window count).
2799		When the optional argument is "#", the number of the last
2800		accessed window is returned (where |CTRL-W_p| goes to).
2801		If there is no previous window 0 is returned.
2802		The number can be used with |CTRL-W_w| and ":wincmd w"
2803		|:wincmd|.
2804
2805							*winrestcmd()*
2806winrestcmd()	Returns a sequence of |:resize| commands that should restore
2807		the current window sizes.  Only works properly when no windows
2808		are opened or closed and the current window is unchanged.
2809		Example: >
2810			:let cmd = winrestcmd()
2811			:call MessWithWindowSizes()
2812			:exe cmd
2813
2814winwidth({nr})						*winwidth()*
2815		The result is a Number, which is the width of window {nr}.
2816		When {nr} is zero, the width of the current window is
2817		returned.  When window {nr} doesn't exist, -1 is returned.
2818		An existing window always has a width of zero or more.
2819		Examples: >
2820  :echo "The current window has " . winwidth(0) . " columns."
2821  :if winwidth(0) <= 50
2822  :  exe "normal 50\<C-W>|"
2823  :endif
2824<
2825
2826							*feature-list*
2827There are three types of features:
28281.  Features that are only supported when they have been enabled when Vim
2829    was compiled |+feature-list|.  Example: >
2830	:if has("cindent")
28312.  Features that are only supported when certain conditions have been met.
2832    Example: >
2833	:if has("gui_running")
2834<							*has-patch*
28353.  Included patches.  First check |v:version| for the version of Vim.
2836    Then the "patch123" feature means that patch 123 has been included for
2837    this version.  Example (checking version 6.2.148 or later): >
2838	:if v:version > 602 || v:version == 602 && has("patch148")
2839
2840all_builtin_terms	Compiled with all builtin terminals enabled.
2841amiga			Amiga version of Vim.
2842arabic			Compiled with Arabic support |Arabic|.
2843arp			Compiled with ARP support (Amiga).
2844autocmd			Compiled with autocommands support.
2845balloon_eval		Compiled with |balloon-eval| support.
2846beos			BeOS version of Vim.
2847browse			Compiled with |:browse| support, and browse() will
2848			work.
2849builtin_terms		Compiled with some builtin terminals.
2850byte_offset		Compiled with support for 'o' in 'statusline'
2851cindent			Compiled with 'cindent' support.
2852clientserver		Compiled with remote invocation support |clientserver|.
2853clipboard		Compiled with 'clipboard' support.
2854cmdline_compl		Compiled with |cmdline-completion| support.
2855cmdline_hist		Compiled with |cmdline-history| support.
2856cmdline_info		Compiled with 'showcmd' and 'ruler' support.
2857comments		Compiled with |'comments'| support.
2858cryptv			Compiled with encryption support |encryption|.
2859cscope			Compiled with |cscope| support.
2860compatible		Compiled to be very Vi compatible.
2861debug			Compiled with "DEBUG" defined.
2862dialog_con		Compiled with console dialog support.
2863dialog_gui		Compiled with GUI dialog support.
2864diff			Compiled with |vimdiff| and 'diff' support.
2865digraphs		Compiled with support for digraphs.
2866dnd			Compiled with support for the "~ register |quote_~|.
2867dos32			32 bits DOS (DJGPP) version of Vim.
2868dos16			16 bits DOS version of Vim.
2869ebcdic			Compiled on a machine with ebcdic character set.
2870emacs_tags		Compiled with support for Emacs tags.
2871eval			Compiled with expression evaluation support.  Always
2872			true, of course!
2873ex_extra		Compiled with extra Ex commands |+ex_extra|.
2874extra_search		Compiled with support for |'incsearch'| and
2875			|'hlsearch'|
2876farsi			Compiled with Farsi support |farsi|.
2877file_in_path		Compiled with support for |gf| and |<cfile>|
2878find_in_path		Compiled with support for include file searches
2879			|+find_in_path|.
2880fname_case		Case in file names matters (for Amiga, MS-DOS, and
2881			Windows this is not present).
2882folding			Compiled with |folding| support.
2883footer			Compiled with GUI footer support. |gui-footer|
2884fork			Compiled to use fork()/exec() instead of system().
2885gettext			Compiled with message translation |multi-lang|
2886gui			Compiled with GUI enabled.
2887gui_athena		Compiled with Athena GUI.
2888gui_beos		Compiled with BeOS GUI.
2889gui_gtk			Compiled with GTK+ GUI (any version).
2890gui_gtk2		Compiled with GTK+ 2 GUI (gui_gtk is also defined).
2891gui_kde			Compiled with KDE GUI |KVim|
2892gui_mac			Compiled with Macintosh GUI.
2893gui_motif		Compiled with Motif GUI.
2894gui_photon		Compiled with Photon GUI.
2895gui_win32		Compiled with MS Windows Win32 GUI.
2896gui_win32s		idem, and Win32s system being used (Windows 3.1)
2897gui_running		Vim is running in the GUI, or it will start soon.
2898hangul_input		Compiled with Hangul input support. |hangul|
2899iconv			Can use iconv() for conversion.
2900insert_expand		Compiled with support for CTRL-X expansion commands in
2901			Insert mode.
2902jumplist		Compiled with |jumplist| support.
2903keymap			Compiled with 'keymap' support.
2904langmap			Compiled with 'langmap' support.
2905libcall			Compiled with |libcall()| support.
2906linebreak		Compiled with 'linebreak', 'breakat' and 'showbreak'
2907			support.
2908lispindent		Compiled with support for lisp indenting.
2909listcmds		Compiled with commands for the buffer list |:files|
2910			and the argument list |arglist|.
2911localmap		Compiled with local mappings and abbr. |:map-local|
2912mac			Macintosh version of Vim.
2913macunix			Macintosh version of Vim, using Unix files (OS-X).
2914menu			Compiled with support for |:menu|.
2915mksession		Compiled with support for |:mksession|.
2916modify_fname		Compiled with file name modifiers. |filename-modifiers|
2917mouse			Compiled with support mouse.
2918mouseshape		Compiled with support for 'mouseshape'.
2919mouse_dec		Compiled with support for Dec terminal mouse.
2920mouse_gpm		Compiled with support for gpm (Linux console mouse)
2921mouse_netterm		Compiled with support for netterm mouse.
2922mouse_pterm		Compiled with support for qnx pterm mouse.
2923mouse_xterm		Compiled with support for xterm mouse.
2924multi_byte		Compiled with support for editing Korean et al.
2925multi_byte_ime		Compiled with support for IME input method.
2926multi_lang		Compiled with support for multiple languages.
2927mzscheme		Compiled with MzScheme interface |mzscheme|.
2928netbeans_intg		Compiled with support for |netbeans|.
2929ole			Compiled with OLE automation support for Win32.
2930os2			OS/2 version of Vim.
2931osfiletype		Compiled with support for osfiletypes |+osfiletype|
2932path_extra		Compiled with up/downwards search in 'path' and 'tags'
2933perl			Compiled with Perl interface.
2934postscript		Compiled with PostScript file printing.
2935printer			Compiled with |:hardcopy| support.
2936python			Compiled with Python interface.
2937qnx			QNX version of Vim.
2938quickfix		Compiled with |quickfix| support.
2939rightleft		Compiled with 'rightleft' support.
2940ruby			Compiled with Ruby interface |ruby|.
2941scrollbind		Compiled with 'scrollbind' support.
2942showcmd			Compiled with 'showcmd' support.
2943signs			Compiled with |:sign| support.
2944smartindent		Compiled with 'smartindent' support.
2945sniff			Compiled with SNiFF interface support.
2946statusline		Compiled with support for 'statusline', 'rulerformat'
2947			and special formats of 'titlestring' and 'iconstring'.
2948sun_workshop		Compiled with support for Sun |workshop|.
2949syntax			Compiled with syntax highlighting support.
2950syntax_items		There are active syntax highlighting items for the
2951			current buffer.
2952system			Compiled to use system() instead of fork()/exec().
2953tag_binary		Compiled with binary searching in tags files
2954			|tag-binary-search|.
2955tag_old_static		Compiled with support for old static tags
2956			|tag-old-static|.
2957tag_any_white		Compiled with support for any white characters in tags
2958			files |tag-any-white|.
2959tcl			Compiled with Tcl interface.
2960terminfo		Compiled with terminfo instead of termcap.
2961termresponse		Compiled with support for |t_RV| and |v:termresponse|.
2962textobjects		Compiled with support for |text-objects|.
2963tgetent			Compiled with tgetent support, able to use a termcap
2964			or terminfo file.
2965title			Compiled with window title support |'title'|.
2966toolbar			Compiled with support for |gui-toolbar|.
2967unix			Unix version of Vim.
2968user_commands		User-defined commands.
2969viminfo			Compiled with viminfo support.
2970vim_starting		True while initial source'ing takes place.
2971vertsplit		Compiled with vertically split windows |:vsplit|.
2972virtualedit		Compiled with 'virtualedit' option.
2973visual			Compiled with Visual mode.
2974visualextra		Compiled with extra Visual mode commands.
2975			|blockwise-operators|.
2976vms			VMS version of Vim.
2977vreplace		Compiled with |gR| and |gr| commands.
2978wildignore		Compiled with 'wildignore' option.
2979wildmenu		Compiled with 'wildmenu' option.
2980windows			Compiled with support for more than one window.
2981winaltkeys		Compiled with 'winaltkeys' option.
2982win16			Win16 version of Vim (MS-Windows 3.1).
2983win32			Win32 version of Vim (MS-Windows 95/98/ME/NT/2000/XP).
2984win64			Win64 version of Vim (MS-Windows 64 bit).
2985win32unix		Win32 version of Vim, using Unix files (Cygwin)
2986win95			Win32 version for MS-Windows 95/98/ME.
2987writebackup		Compiled with 'writebackup' default on.
2988xfontset		Compiled with X fontset support |xfontset|.
2989xim			Compiled with X input method support |xim|.
2990xsmp			Compiled with X session management support.
2991xsmp_interact		Compiled with interactive X session management support.
2992xterm_clipboard		Compiled with support for xterm clipboard.
2993xterm_save		Compiled with support for saving and restoring the
2994			xterm screen.
2995x11			Compiled with X11 support.
2996
2997							*string-match*
2998Matching a pattern in a String
2999
3000A regexp pattern as explained at |pattern| is normally used to find a match in
3001the buffer lines.  When a pattern is used to find a match in a String, almost
3002everything works in the same way.  The difference is that a String is handled
3003like it is one line.  When it contains a "\n" character, this is not seen as a
3004line break for the pattern.  It can be matched with a "\n" in the pattern, or
3005with ".".  Example: >
3006	:let a = "aaaa\nxxxx"
3007	:echo matchstr(a, "..\n..")
3008	aa
3009	xx
3010	:echo matchstr(a, "a.x")
3011	a
3012	x
3013
3014Don't forget that "^" will only match at the first character of the String and
3015"$" at the last character of the string.  They don't match after or before a
3016"\n".
3017
3018==============================================================================
30195. Defining functions					*user-functions*
3020
3021New functions can be defined.  These can be called just like builtin
3022functions.  The function executes a sequence of Ex commands.  Normal mode
3023commands can be executed with the |:normal| command.
3024
3025The function name must start with an uppercase letter, to avoid confusion with
3026builtin functions.  To prevent from using the same name in different scripts
3027avoid obvious, short names.  A good habit is to start the function name with
3028the name of the script, e.g., "HTMLcolor()".
3029
3030It's also possible to use curly braces, see |curly-braces-names|.
3031
3032							*local-function*
3033A function local to a script must start with "s:".  A local script function
3034can only be called from within the script and from functions, user commands
3035and autocommands defined in the script.  It is also possible to call the
3036function from a mappings defined in the script, but then |<SID>| must be used
3037instead of "s:" when the mapping is expanded outside of the script.
3038
3039					*:fu* *:function* *E128* *E129* *E123*
3040:fu[nction]		List all functions and their arguments.
3041
3042:fu[nction] {name}	List function {name}.
3043							*E124* *E125*
3044:fu[nction][!] {name}([arguments]) [range] [abort]
3045			Define a new function by the name {name}.  The name
3046			must be made of alphanumeric characters and '_', and
3047			must start with a capital or "s:" (see above).
3048						*function-argument* *a:var*
3049			An argument can be defined by giving its name.  In the
3050			function this can then be used as "a:name" ("a:" for
3051			argument).
3052			Up to 20 arguments can be given, separated by commas.
3053			Finally, an argument "..." can be specified, which
3054			means that more arguments may be following.  In the
3055			function they can be used as "a:1", "a:2", etc.  "a:0"
3056			is set to the number of extra arguments (which can be
3057			0).
3058			When not using "...", the number of arguments in a
3059			function call must be equal to the number of named
3060			arguments.  When using "...", the number of arguments
3061			may be larger.
3062			It is also possible to define a function without any
3063			arguments.  You must still supply the () then.
3064			The body of the function follows in the next lines,
3065			until the matching |:endfunction|.  It is allowed to
3066			define another function inside a function body.
3067								*E127* *E122*
3068			When a function by this name already exists and [!] is
3069			not used an error message is given.  When [!] is used,
3070			an existing function is silently replaced.  Unless it
3071			is currently being executed, that is an error.
3072						*a:firstline* *a:lastline*
3073			When the [range] argument is added, the function is
3074			expected to take care of a range itself.  The range is
3075			passed as "a:firstline" and "a:lastline".  If [range]
3076			is excluded, ":{range}call" will call the function for
3077			each line in the range, with the cursor on the start
3078			of each line.  See |function-range-example|.
3079			When the [abort] argument is added, the function will
3080			abort as soon as an error is detected.
3081			The last used search pattern and the redo command "."
3082			will not be changed by the function.
3083
3084					*:endf* *:endfunction* *E126* *E193*
3085:endf[unction]		The end of a function definition.  Must be on a line
3086			by its own, without other commands.
3087
3088					*:delf* *:delfunction* *E130* *E131*
3089:delf[unction] {name}	Delete function {name}.
3090
3091							*:retu* *:return* *E133*
3092:retu[rn] [expr]	Return from a function.  When "[expr]" is given, it is
3093			evaluated and returned as the result of the function.
3094			If "[expr]" is not given, the number 0 is returned.
3095			When a function ends without an explicit ":return",
3096			the number 0 is returned.
3097			Note that there is no check for unreachable lines,
3098			thus there is no warning if commands follow ":return".
3099
3100			If the ":return" is used after a |:try| but before the
3101			matching |:finally| (if present), the commands
3102			following the ":finally" up to the matching |:endtry|
3103			are executed first.  This process applies to all
3104			nested ":try"s inside the function.  The function
3105			returns at the outermost ":endtry".
3106
3107
3108Inside a function variables can be used.  These are local variables, which
3109will disappear when the function returns.  Global variables need to be
3110accessed with "g:".
3111
3112Example: >
3113  :function Table(title, ...)
3114  :  echohl Title
3115  :  echo a:title
3116  :  echohl None
3117  :  let idx = 1
3118  :  while idx <= a:0
3119  :    echo a:{idx} . ' '
3120  :    let idx = idx + 1
3121  :  endwhile
3122  :  return idx
3123  :endfunction
3124
3125This function can then be called with: >
3126  let lines = Table("Table", "line1", "line2")
3127  let lines = Table("Empty Table")
3128
3129To return more than one value, pass the name of a global variable: >
3130  :function Compute(n1, n2, divname)
3131  :  if a:n2 == 0
3132  :    return "fail"
3133  :  endif
3134  :  let g:{a:divname} = a:n1 / a:n2
3135  :  return "ok"
3136  :endfunction
3137
3138This function can then be called with: >
3139  :let success = Compute(13, 1324, "div")
3140  :if success == "ok"
3141  :  echo div
3142  :endif
3143
3144An alternative is to return a command that can be executed.  This also works
3145with local variables in a calling function.  Example: >
3146  :function Foo()
3147  :  execute Bar()
3148  :  echo "line " . lnum . " column " . col
3149  :endfunction
3150
3151  :function Bar()
3152  :  return "let lnum = " . line(".") . " | let col = " . col(".")
3153  :endfunction
3154
3155The names "lnum" and "col" could also be passed as argument to Bar(), to allow
3156the caller to set the names.
3157
3158							*:cal* *:call* *E107*
3159:[range]cal[l] {name}([arguments])
3160		Call a function.  The name of the function and its arguments
3161		are as specified with |:function|.  Up to 20 arguments can be
3162		used.
3163		Without a range and for functions that accept a range, the
3164		function is called once.  When a range is given the cursor is
3165		positioned at the start of the first line before executing the
3166		function.
3167		When a range is given and the function doesn't handle it
3168		itself, the function is executed for each line in the range,
3169		with the cursor in the first column of that line.  The cursor
3170		is left at the last line (possibly moved by the last function
3171		call).  The arguments are re-evaluated for each line.  Thus
3172		this works:
3173						*function-range-example*  >
3174	:function Mynumber(arg)
3175	:  echo line(".") . " " . a:arg
3176	:endfunction
3177	:1,5call Mynumber(getline("."))
3178<
3179		The "a:firstline" and "a:lastline" are defined anyway, they
3180		can be used to do something different at the start or end of
3181		the range.
3182
3183		Example of a function that handles the range itself: >
3184
3185	:function Cont() range
3186	:  execute (a:firstline + 1) . "," . a:lastline . 's/^/\t\\ '
3187	:endfunction
3188	:4,8call Cont()
3189<
3190		This function inserts the continuation character "\" in front
3191		of all the lines in the range, except the first one.
3192
3193								*E132*
3194The recursiveness of user functions is restricted with the |'maxfuncdepth'|
3195option.
3196
3197							*autoload-functions*
3198When using many or large functions, it's possible to automatically define them
3199only when they are used.  Use the FuncUndefined autocommand event with a
3200pattern that matches the function(s) to be defined.  Example: >
3201
3202	:au FuncUndefined BufNet* source ~/vim/bufnetfuncs.vim
3203
3204The file "~/vim/bufnetfuncs.vim" should then define functions that start with
3205"BufNet".  Also see |FuncUndefined|.
3206
3207==============================================================================
32086. Curly braces names					*curly-braces-names*
3209
3210Wherever you can use a variable, you can use a "curly braces name" variable.
3211This is a regular variable name with one or more expressions wrapped in braces
3212{} like this: >
3213	my_{adjective}_variable
3214
3215When Vim encounters this, it evaluates the expression inside the braces, puts
3216that in place of the expression, and re-interprets the whole as a variable
3217name.  So in the above example, if the variable "adjective" was set to
3218"noisy", then the reference would be to "my_noisy_variable", whereas if
3219"adjective" was set to "quiet", then it would be to "my_quiet_variable".
3220
3221One application for this is to create a set of variables governed by an option
3222value.  For example, the statement >
3223	echo my_{&background}_message
3224
3225would output the contents of "my_dark_message" or "my_light_message" depending
3226on the current value of 'background'.
3227
3228You can use multiple brace pairs: >
3229	echo my_{adverb}_{adjective}_message
3230..or even nest them: >
3231	echo my_{ad{end_of_word}}_message
3232where "end_of_word" is either "verb" or "jective".
3233
3234However, the expression inside the braces must evaluate to a valid single
3235variable name. e.g. this is invalid: >
3236	:let foo='a + b'
3237	:echo c{foo}d
3238.. since the result of expansion is "ca + bd", which is not a variable name.
3239
3240						*curly-braces-function-names*
3241You can call and define functions by an evaluated name in a similar way.
3242Example: >
3243	:let func_end='whizz'
3244	:call my_func_{func_end}(parameter)
3245
3246This would call the function "my_func_whizz(parameter)".
3247
3248==============================================================================
32497. Commands						*expression-commands*
3250
3251:let {var-name} = {expr1}				*:let* *E18*
3252			Set internal variable {var-name} to the result of the
3253			expression {expr1}.  The variable will get the type
3254			from the {expr}.  If {var-name} didn't exist yet, it
3255			is created.
3256
3257:let ${env-name} = {expr1}			*:let-environment* *:let-$*
3258			Set environment variable {env-name} to the result of
3259			the expression {expr1}.  The type is always String.
3260
3261:let @{reg-name} = {expr1}			*:let-register* *:let-@*
3262			Write the result of the expression {expr1} in register
3263			{reg-name}.  {reg-name} must be a single letter, and
3264			must be the name of a writable register (see
3265			|registers|).  "@@" can be used for the unnamed
3266			register, "@/" for the search pattern.
3267			If the result of {expr1} ends in a <CR> or <NL>, the
3268			register will be linewise, otherwise it will be set to
3269			characterwise.
3270			This can be used to clear the last search pattern: >
3271				:let @/ = ""
3272<			This is different from searching for an empty string,
3273			that would match everywhere.
3274
3275:let &{option-name} = {expr1}			*:let-option* *:let-star*
3276			Set option {option-name} to the result of the
3277			expression {expr1}.  The value is always converted to
3278			the type of the option.
3279			For an option local to a window or buffer the effect
3280			is just like using the |:set| command: both the local
3281			value and the global value is changed.
3282
3283:let &l:{option-name} = {expr1}
3284			Like above, but only set the local value of an option
3285			(if there is one).  Works like |:setlocal|.
3286
3287:let &g:{option-name} = {expr1}
3288			Like above, but only set the global value of an option
3289			(if there is one).  Works like |:setglobal|.
3290
3291							*E106*
3292:let {var-name}	..	List the value of variable {var-name}.  Several
3293			variable names may be given.
3294
3295:let			List the values of all variables.
3296
3297							*:unlet* *:unl* *E108*
3298:unl[et][!] {var-name} ...
3299			Remove the internal variable {var-name}.  Several
3300			variable names can be given, they are all removed.
3301			With [!] no error message is given for non-existing
3302			variables.
3303
3304:if {expr1}			*:if* *:endif* *:en* *E171* *E579* *E580*
3305:en[dif]		Execute the commands until the next matching ":else"
3306			or ":endif" if {expr1} evaluates to non-zero.
3307
3308			From Vim version 4.5 until 5.0, every Ex command in
3309			between the ":if" and ":endif" is ignored.  These two
3310			commands were just to allow for future expansions in a
3311			backwards compatible way.  Nesting was allowed.  Note
3312			that any ":else" or ":elseif" was ignored, the "else"
3313			part was not executed either.
3314
3315			You can use this to remain compatible with older
3316			versions: >
3317				:if version >= 500
3318				:  version-5-specific-commands
3319				:endif
3320<			The commands still need to be parsed to find the
3321			"endif".  Sometimes an older Vim has a problem with a
3322			new command.  For example, ":silent" is recognized as
3323			a ":substitute" command.  In that case ":execute" can
3324			avoid problems: >
3325				:if version >= 600
3326				:  execute "silent 1,$delete"
3327				:endif
3328<
3329			NOTE: The ":append" and ":insert" commands don't work
3330			properly in between ":if" and ":endif".
3331
3332						*:else* *:el* *E581* *E583*
3333:el[se]			Execute the commands until the next matching ":else"
3334			or ":endif" if they previously were not being
3335			executed.
3336
3337					*:elseif* *:elsei* *E582* *E584*
3338:elsei[f] {expr1}	Short for ":else" ":if", with the addition that there
3339			is no extra ":endif".
3340
3341:wh[ile] {expr1}			*:while* *:endwhile* *:wh* *:endw*
3342							*E170* *E585* *E588*
3343:endw[hile]		Repeat the commands between ":while" and ":endwhile",
3344			as long as {expr1} evaluates to non-zero.
3345			When an error is detected from a command inside the
3346			loop, execution continues after the "endwhile".
3347
3348			NOTE: The ":append" and ":insert" commands don't work
3349			properly inside a ":while" loop.
3350
3351						*:continue* *:con* *E586*
3352:con[tinue]		When used inside a ":while", jumps back to the
3353			":while".  If it is used after a |:try| inside the
3354			":while" but before the matching |:finally| (if
3355			present), the commands following the ":finally" up to
3356			the matching |:endtry| are executed first.  This
3357			process applies to all nested ":try"s inside the
3358			":while".  The outermost ":endtry" then jumps back to
3359			the ":while".
3360
3361						*:break* *:brea* *E587*
3362:brea[k]		When used inside a ":while", skips to the command
3363			after the matching ":endwhile".  If it is used after
3364			a |:try| inside the ":while" but before the matching
3365			|:finally| (if present), the commands following the
3366			":finally" up to the matching |:endtry| are executed
3367			first.  This process applies to all nested ":try"s
3368			inside the ":while".  The outermost ":endtry" then
3369			jumps to the command after the ":endwhile".
3370
3371:try				*:try* *:endt* *:endtry* *E600* *E601* *E602*
3372:endt[ry]		Change the error handling for the commands between
3373			":try" and ":endtry" including everything being
3374			executed across ":source" commands, function calls,
3375			or autocommand invocations.
3376
3377			When an error or interrupt is detected and there is
3378			a |:finally| command following, execution continues
3379			after the ":finally".  Otherwise, or when the
3380			":endtry" is reached thereafter, the next
3381			(dynamically) surrounding ":try" is checked for
3382			a corresponding ":finally" etc.  Then the script
3383			processing is terminated.  (Whether a function
3384			definition has an "abort" argument does not matter.)
3385			Example: >
3386		:try | edit too much | finally | echo "cleanup" | endtry
3387		:echo "impossible"	" not reached, script terminated above
3388<
3389			Moreover, an error or interrupt (dynamically) inside
3390			":try" and ":endtry" is converted to an exception.  It
3391			can be caught as if it were thrown by a |:throw|
3392			command (see |:catch|).  In this case, the script
3393			processing is not terminated.
3394
3395			The value "Vim:Interrupt" is used for an interrupt
3396			exception.  An error in a Vim command is converted
3397			to a value of the form "Vim({command}):{errmsg}",
3398			other errors are converted to a value of the form
3399			"Vim:{errmsg}".  {command} is the full command name,
3400			and {errmsg} is the message that is displayed if the
3401			error exception is not caught, always beginning with
3402			the error number.
3403			Examples: >
3404		:try | sleep 100 | catch /^Vim:Interrupt$/ | endtry
3405		:try | edit | catch /^Vim(edit):E\d\+/ | echo "error" | endtry
3406<
3407					*:cat* *:catch* *E603* *E604* *E605*
3408:cat[ch] /{pattern}/	The following commands until the next ":catch",
3409			|:finally|, or |:endtry| that belongs to the same
3410			|:try| as the ":catch" are executed when an exception
3411			matching {pattern} is being thrown and has not yet
3412			been caught by a previous ":catch".  Otherwise, these
3413			commands are skipped.
3414			When {pattern} is omitted all errors are caught.
3415			Examples: >
3416		:catch /^Vim:Interrupt$/	" catch interrupts (CTRL-C)
3417		:catch /^Vim\%((\a\+)\)\=:E/	" catch all Vim errors
3418		:catch /^Vim\%((\a\+)\)\=:/	" catch errors and interrupts
3419		:catch /^Vim(write):/		" catch all errors in :write
3420		:catch /^Vim\%((\a\+)\)\=:E123/	" catch error E123
3421		:catch /my-exception/		" catch user exception
3422		:catch /.*/			" catch everything
3423		:catch				" same as /.*/
3424<
3425			Another character can be used instead of / around the
3426			{pattern}, so long as it does not have a special
3427			meaning (e.g., '|' or '"') and doesn't occur inside
3428			{pattern}.
3429			NOTE: It is not reliable to ":catch" the TEXT of
3430			an error message because it may vary in different
3431			locales.
3432
3433					*:fina* *:finally* *E606* *E607*
3434:fina[lly]		The following commands until the matching |:endtry|
3435			are executed whenever the part between the matching
3436			|:try| and the ":finally" is left:  either by falling
3437			through to the ":finally" or by a |:continue|,
3438			|:break|, |:finish|, or |:return|, or by an error or
3439			interrupt or exception (see |:throw|).
3440
3441							*:th* *:throw* *E608*
3442:th[row] {expr1}	The {expr1} is evaluated and thrown as an exception.
3443			If the ":throw" is used after a |:try| but before the
3444			first corresponding |:catch|, commands are skipped
3445			until the first ":catch" matching {expr1} is reached.
3446			If there is no such ":catch" or if the ":throw" is
3447			used after a ":catch" but before the |:finally|, the
3448			commands following the ":finally" (if present) up to
3449			the matching |:endtry| are executed.  If the ":throw"
3450			is after the ":finally", commands up to the ":endtry"
3451			are skipped.  At the ":endtry", this process applies
3452			again for the next dynamically surrounding ":try"
3453			(which may be found in a calling function or sourcing
3454			script), until a matching ":catch" has been found.
3455			If the exception is not caught, the command processing
3456			is terminated.
3457			Example: >
3458		:try | throw "oops" | catch /^oo/ | echo "caught" | endtry
3459<
3460
3461							*:ec* *:echo*
3462:ec[ho] {expr1} ..	Echoes each {expr1}, with a space in between.  The
3463			first {expr1} starts on a new line.
3464			Also see |:comment|.
3465			Use "\n" to start a new line.  Use "\r" to move the
3466			cursor to the first column.
3467			Uses the highlighting set by the |:echohl| command.
3468			Cannot be followed by a comment.
3469			Example: >
3470		:echo "the value of 'shell' is" &shell
3471<			A later redraw may make the message disappear again.
3472			To avoid that a command from before the ":echo" causes
3473			a redraw afterwards (redraws are often postponed until
3474			you type something), force a redraw with the |:redraw|
3475			command.  Example: >
3476		:new | redraw | echo "there is a new window"
3477<
3478							*:echon*
3479:echon {expr1} ..	Echoes each {expr1}, without anything added.  Also see
3480			|:comment|.
3481			Uses the highlighting set by the |:echohl| command.
3482			Cannot be followed by a comment.
3483			Example: >
3484				:echon "the value of 'shell' is " &shell
3485<
3486			Note the difference between using ":echo", which is a
3487			Vim command, and ":!echo", which is an external shell
3488			command: >
3489		:!echo %		--> filename
3490<			The arguments of ":!" are expanded, see |:_%|. >
3491		:!echo "%"		--> filename or "filename"
3492<			Like the previous example.  Whether you see the double
3493			quotes or not depends on your 'shell'. >
3494		:echo %			--> nothing
3495<			The '%' is an illegal character in an expression. >
3496		:echo "%"		--> %
3497<			This just echoes the '%' character. >
3498		:echo expand("%")	--> filename
3499<			This calls the expand() function to expand the '%'.
3500
3501							*:echoh* *:echohl*
3502:echoh[l] {name}	Use the highlight group {name} for the following
3503			|:echo|, |:echon| and |:echomsg| commands.  Also used
3504			for the |input()| prompt.  Example: >
3505		:echohl WarningMsg | echo "Don't panic!" | echohl None
3506<			Don't forget to set the group back to "None",
3507			otherwise all following echo's will be highlighted.
3508
3509							*:echom* *:echomsg*
3510:echom[sg] {expr1} ..	Echo the expression(s) as a true message, saving the
3511			message in the |message-history|.
3512			Spaces are placed between the arguments as with the
3513			|:echo| command.  But unprintable characters are
3514			displayed, not interpreted.
3515			Uses the highlighting set by the |:echohl| command.
3516			Example: >
3517		:echomsg "It's a Zizzer Zazzer Zuzz, as you can plainly see."
3518<
3519							*:echoe* *:echoerr*
3520:echoe[rr] {expr1} ..	Echo the expression(s) as an error message, saving the
3521			message in the |message-history|.  When used in a
3522			script or function the line number will be added.
3523			Spaces are placed between the arguments as with the
3524			:echo command.  When used inside a try conditional,
3525			the message is raised as an error exception instead
3526			(see |try-echoerr|).
3527			Example: >
3528		:echoerr "This script just failed!"
3529<			If you just want a highlighted message use |:echohl|.
3530			And to get a beep: >
3531		:exe "normal \<Esc>"
3532<
3533							*:exe* *:execute*
3534:exe[cute] {expr1} ..	Executes the string that results from the evaluation
3535			of {expr1} as an Ex command.  Multiple arguments are
3536			concatenated, with a space in between.  {expr1} is
3537			used as the processed command, command line editing
3538			keys are not recognized.
3539			Cannot be followed by a comment.
3540			Examples: >
3541		:execute "buffer " nextbuf
3542		:execute "normal " count . "w"
3543<
3544			":execute" can be used to append a command to commands
3545			that don't accept a '|'.  Example: >
3546		:execute '!ls' | echo "theend"
3547
3548<			":execute" is also a nice way to avoid having to type
3549			control characters in a Vim script for a ":normal"
3550			command: >
3551		:execute "normal ixxx\<Esc>"
3552<			This has an <Esc> character, see |expr-string|.
3553
3554			Note: The executed string may be any command-line, but
3555			you cannot start or end a "while" or "if" command.
3556			Thus this is illegal: >
3557		:execute 'while i > 5'
3558		:execute 'echo "test" | break'
3559<
3560			It is allowed to have a "while" or "if" command
3561			completely in the executed string: >
3562		:execute 'while i < 5 | echo i | let i = i + 1 | endwhile'
3563<
3564
3565							*:comment*
3566			":execute", ":echo" and ":echon" cannot be followed by
3567			a comment directly, because they see the '"' as the
3568			start of a string.  But, you can use '|' followed by a
3569			comment.  Example: >
3570		:echo "foo" | "this is a comment
3571
3572==============================================================================
35738. Exception handling					*exception-handling*
3574
3575The Vim script language comprises an exception handling feature.  This section
3576explains how it can be used in a Vim script.
3577
3578Exceptions may be raised by Vim on an error or on interrupt, see
3579|catch-errors| and |catch-interrupt|.  You can also explicitly throw an
3580exception by using the ":throw" command, see |throw-catch|.
3581
3582
3583TRY CONDITIONALS					*try-conditionals*
3584
3585Exceptions can be caught or can cause cleanup code to be executed.  You can
3586use a try conditional to specify catch clauses (that catch exceptions) and/or
3587a finally clause (to be executed for cleanup).
3588   A try conditional begins with a |:try| command and ends at the matching
3589|:endtry| command.  In between, you can use a |:catch| command to start
3590a catch clause, or a |:finally| command to start a finally clause.  There may
3591be none or multiple catch clauses, but there is at most one finally clause,
3592which must not be followed by any catch clauses.  The lines before the catch
3593clauses and the finally clause is called a try block. >
3594
3595     :try
3596     :  ...
3597     :  ...				TRY BLOCK
3598     :  ...
3599     :catch /{pattern}/
3600     :  ...
3601     :  ...				CATCH CLAUSE
3602     :  ...
3603     :catch /{pattern}/
3604     :  ...
3605     :  ...				CATCH CLAUSE
3606     :  ...
3607     :finally
3608     :  ...
3609     :  ...				FINALLY CLAUSE
3610     :  ...
3611     :endtry
3612
3613The try conditional allows to watch code for exceptions and to take the
3614appropriate actions.  Exceptions from the try block may be caught.  Exceptions
3615from the try block and also the catch clauses may cause cleanup actions.
3616   When no exception is thrown during execution of the try block, the control
3617is transferred to the finally clause, if present.  After its execution, the
3618script continues with the line following the ":endtry".
3619   When an exception occurs during execution of the try block, the remaining
3620lines in the try block are skipped.  The exception is matched against the
3621patterns specified as arguments to the ":catch" commands.  The catch clause
3622after the first matching ":catch" is taken, other catch clauses are not
3623executed.  The catch clause ends when the next ":catch", ":finally", or
3624":endtry" command is reached - whatever is first.  Then, the finally clause
3625(if present) is executed.  When the ":endtry" is reached, the script execution
3626continues in the following line as usual.
3627   When an exception that does not match any of the patterns specified by the
3628":catch" commands is thrown in the try block, the exception is not caught by
3629that try conditional and none of the catch clauses is executed.  Only the
3630finally clause, if present, is taken.  The exception pends during execution of
3631the finally clause.  It is resumed at the ":endtry", so that commands after
3632the ":endtry" are not executed and the exception might be caught elsewhere,
3633see |try-nesting|.
3634   When during execution of a catch clause another exception is thrown, the
3635remaining lines in that catch clause are not executed.  The new exception is
3636not matched against the patterns in any of the ":catch" commands of the same
3637try conditional and none of its catch clauses is taken.  If there is, however,
3638a finally clause, it is executed, and the exception pends during its
3639execution.  The commands following the ":endtry" are not executed.  The new
3640exception might, however, be caught elsewhere, see |try-nesting|.
3641   When during execution of the finally clause (if present) an exception is
3642thrown, the remaining lines in the finally clause are skipped.  If the finally
3643clause has been taken because of an exception from the try block or one of the
3644catch clauses, the original (pending) exception is discarded.  The commands
3645following the ":endtry" are not executed, and the exception from the finally
3646clause is propagated and can be caught elsewhere, see |try-nesting|.
3647
3648The finally clause is also executed, when a ":break" or ":continue" for
3649a ":while" loop enclosing the complete try conditional is executed from the
3650try block or a catch clause.  Or when a ":return" or ":finish" is executed
3651from the try block or a catch clause of a try conditional in a function or
3652sourced script, respectively.  The ":break", ":continue", ":return", or
3653":finish" pends during execution of the finally clause and is resumed when the
3654":endtry" is reached.  It is, however, discarded when an exception is thrown
3655from the finally clause.
3656   When a ":break" or ":continue" for a ":while" loop enclosing the complete
3657try conditional or when a ":return" or ":finish" is encountered in the finally
3658clause, the rest of the finally clause is skipped, and the ":break",
3659":continue", ":return" or ":finish" is executed as usual.  If the finally
3660clause has been taken because of an exception or an earlier ":break",
3661":continue", ":return", or ":finish" from the try block or a catch clause,
3662this pending exception or command is discarded.
3663
3664For examples see |throw-catch| and |try-finally|.
3665
3666
3667NESTING	OF TRY CONDITIONALS				*try-nesting*
3668
3669Try conditionals can be nested arbitrarily.  That is, a complete try
3670conditional can be put into the try block, a catch clause, or the finally
3671clause of another try conditional.  If the inner try conditional does not
3672catch an exception thrown in its try block or throws a new exception from one
3673of its catch clauses or its finally clause, the outer try conditional is
3674checked according to the rules above.  If the inner try conditional is in the
3675try block of the outer try conditional, its catch clauses are checked, but
3676otherwise only the finally clause is executed.  It does not matter for
3677nesting, whether the inner try conditional is directly contained in the outer
3678one, or whether the outer one sources a script or calls a function containing
3679the inner try conditional.
3680
3681When none of the active try conditionals catches an exception, just their
3682finally clauses are executed.  Thereafter, the script processing terminates.
3683An error message is displayed in case of an uncaught exception explicitly
3684thrown by a ":throw" command.  For uncaught error and interrupt exceptions
3685implicitly raised by Vim, the error message(s) or interrupt message are shown
3686as usual.
3687
3688For examples see |throw-catch|.
3689
3690
3691EXAMINING EXCEPTION HANDLING CODE			*except-examine*
3692
3693Exception handling code can get tricky.  If you are in doubt what happens, set
3694'verbose' to 13 or use the ":13verbose" command modifier when sourcing your
3695script file.  Then you see when an exception is thrown, discarded, caught, or
3696finished.  When using a verbosity level of at least 14, things pending in
3697a finally clause are also shown.  This information is also given in debug mode
3698(see |debug-scripts|).
3699
3700
3701THROWING AND CATCHING EXCEPTIONS			*throw-catch*
3702
3703You can throw any number or string as an exception.  Use the |:throw| command
3704and pass the value to be thrown as argument: >
3705	:throw 4711
3706	:throw "string"
3707<							*throw-expression*
3708You can also specify an expression argument.  The expression is then evaluated
3709first, and the result is thrown: >
3710	:throw 4705 + strlen("string")
3711	:throw strpart("strings", 0, 6)
3712
3713An exception might be thrown during evaluation of the argument of the ":throw"
3714command.  Unless it is caught there, the expression evaluation is abandoned.
3715The ":throw" command then does not throw a new exception.
3716   Example: >
3717
3718	:function! Foo(arg)
3719	:  try
3720	:    throw a:arg
3721	:  catch /foo/
3722	:  endtry
3723	:  return 1
3724	:endfunction
3725	:
3726	:function! Bar()
3727	:  echo "in Bar"
3728	:  return 4710
3729	:endfunction
3730	:
3731	:throw Foo("arrgh") + Bar()
3732
3733This throws "arrgh", and "in Bar" is not displayed since Bar() is not
3734executed. >
3735	:throw Foo("foo") + Bar()
3736however displays "in Bar" and throws 4711.
3737
3738Any other command that takes an expression as argument might also be
3739abandoned by an (uncaught) exception during the expression evaluation.  The
3740exception is then propagated to the caller of the command.
3741   Example: >
3742
3743	:if Foo("arrgh")
3744	:  echo "then"
3745	:else
3746	:  echo "else"
3747	:endif
3748
3749Here neither of "then" or "else" is displayed.
3750
3751							*catch-order*
3752Exceptions can be caught by a try conditional with one or more |:catch|
3753commands, see |try-conditionals|.   The values to be caught by each ":catch"
3754command can be specified as a pattern argument.  The subsequent catch clause
3755gets executed when a matching exception is caught.
3756   Example: >
3757
3758	:function! Foo(value)
3759	:  try
3760	:    throw a:value
3761	:  catch /^\d\+$/
3762	:    echo "Number thrown"
3763	:  catch /.*/
3764	:    echo "String thrown"
3765	:  endtry
3766	:endfunction
3767	:
3768	:call Foo(0x1267)
3769	:call Foo('string')
3770
3771The first call to Foo() displays "Number thrown", the second "String thrown".
3772An exception is matched against the ":catch" commands in the order they are
3773specified.  Only the first match counts.  So you should place the more
3774specific ":catch" first.  The following order does not make sense: >
3775
3776	:  catch /.*/
3777	:    echo "String thrown"
3778	:  catch /^\d\+$/
3779	:    echo "Number thrown"
3780
3781The first ":catch" here matches always, so that the second catch clause is
3782never taken.
3783
3784							*throw-variables*
3785If you catch an exception by a general pattern, you may access the exact value
3786in the variable |v:exception|: >
3787
3788	:  catch /^\d\+$/
3789	:    echo "Number thrown.  Value is" v:exception
3790
3791You may also be interested where an exception was thrown.  This is stored in
3792|v:throwpoint|.  Note that "v:exception" and "v:throwpoint" are valid for the
3793exception most recently caught as long it is not finished.
3794   Example: >
3795
3796	:function! Caught()
3797	:  if v:exception != ""
3798	:    echo 'Caught "' . v:exception . '" in ' . v:throwpoint
3799	:  else
3800	:    echo 'Nothing caught'
3801	:  endif
3802	:endfunction
3803	:
3804	:function! Foo()
3805	:  try
3806	:    try
3807	:      try
3808	:	 throw 4711
3809	:      finally
3810	:	 call Caught()
3811	:      endtry
3812	:    catch /.*/
3813	:      call Caught()
3814	:      throw "oops"
3815	:    endtry
3816	:  catch /.*/
3817	:    call Caught()
3818	:  finally
3819	:    call Caught()
3820	:  endtry
3821	:endfunction
3822	:
3823	:call Foo()
3824
3825This displays >
3826
3827	Nothing caught
3828	Caught "4711" in function Foo, line 4
3829	Caught "oops" in function Foo, line 10
3830	Nothing caught
3831
3832A practical example:  The following command ":LineNumber" displays the line
3833number in the script or function where it has been used: >
3834
3835	:function! LineNumber()
3836	:    return substitute(v:throwpoint, '.*\D\(\d\+\).*', '\1', "")
3837	:endfunction
3838	:command! LineNumber try | throw "" | catch | echo LineNumber() | endtry
3839<
3840							*try-nested*
3841An exception that is not caught by a try conditional can be caught by
3842a surrounding try conditional: >
3843
3844	:try
3845	:  try
3846	:    throw "foo"
3847	:  catch /foobar/
3848	:    echo "foobar"
3849	:  finally
3850	:    echo "inner finally"
3851	:  endtry
3852	:catch /foo/
3853	:  echo "foo"
3854	:endtry
3855
3856The inner try conditional does not catch the exception, just its finally
3857clause is executed.  The exception is then caught by the outer try
3858conditional.  The example displays "inner finally" and then "foo".
3859
3860							*throw-from-catch*
3861You can catch an exception and throw a new one to be caught elsewhere from the
3862catch clause: >
3863
3864	:function! Foo()
3865	:  throw "foo"
3866	:endfunction
3867	:
3868	:function! Bar()
3869	:  try
3870	:    call Foo()
3871	:  catch /foo/
3872	:    echo "Caught foo, throw bar"
3873	:    throw "bar"
3874	:  endtry
3875	:endfunction
3876	:
3877	:try
3878	:  call Bar()
3879	:catch /.*/
3880	:  echo "Caught" v:exception
3881	:endtry
3882
3883This displays "Caught foo, throw bar" and then "Caught bar".
3884
3885							*rethrow*
3886There is no real rethrow in the Vim script language, but you may throw
3887"v:exception" instead: >
3888
3889	:function! Bar()
3890	:  try
3891	:    call Foo()
3892	:  catch /.*/
3893	:    echo "Rethrow" v:exception
3894	:    throw v:exception
3895	:  endtry
3896	:endfunction
3897<							*try-echoerr*
3898Note that this method cannot be used to "rethrow" Vim error or interrupt
3899exceptions, because it is not possible to fake Vim internal exceptions.
3900Trying so causes an error exception.  You should throw your own exception
3901denoting the situation.  If you want to cause a Vim error exception containing
3902the original error exception value, you can use the |:echoerr| command: >
3903
3904	:try
3905	:  try
3906	:    asdf
3907	:  catch /.*/
3908	:    echoerr v:exception
3909	:  endtry
3910	:catch /.*/
3911	:  echo v:exception
3912	:endtry
3913
3914This code displays
3915
3916	Vim(echoerr):Vim:E492: Not an editor command:   asdf ~
3917
3918
3919CLEANUP CODE						*try-finally*
3920
3921Scripts often change global settings and restore them at their end.  If the
3922user however interrupts the script by pressing CTRL-C, the settings remain in
3923an inconsistent state.  The same may happen to you in the development phase of
3924a script when an error occurs or you explicitly throw an exception without
3925catching it.  You can solve these problems by using a try conditional with
3926a finally clause for restoring the settings.  Its execution is guaranteed on
3927normal control flow, on error, on an explicit ":throw", and on interrupt.
3928(Note that errors and interrupts from inside the try conditional are converted
3929to exceptions.  When not caught, they terminate the script after the finally
3930clause has been executed.)
3931Example: >
3932
3933	:try
3934	:  let s:saved_ts = &ts
3935	:  set ts=17
3936	:
3937	:  " Do the hard work here.
3938	:
3939	:finally
3940	:  let &ts = s:saved_ts
3941	:  unlet s:saved_ts
3942	:endtry
3943
3944This method should be used locally whenever a function or part of a script
3945changes global settings which need to be restored on failure or normal exit of
3946that function or script part.
3947
3948							*break-finally*
3949Cleanup code works also when the try block or a catch clause is left by
3950a ":continue", ":break", ":return", or ":finish".
3951   Example: >
3952
3953	:let first = 1
3954	:while 1
3955	:  try
3956	:    if first
3957	:      echo "first"
3958	:      let first = 0
3959	:      continue
3960	:    else
3961	:      throw "second"
3962	:    endif
3963	:  catch /.*/
3964	:    echo v:exception
3965	:    break
3966	:  finally
3967	:    echo "cleanup"
3968	:  endtry
3969	:  echo "still in while"
3970	:endwhile
3971	:echo "end"
3972
3973This displays "first", "cleanup", "second", "cleanup", and "end". >
3974
3975	:function! Foo()
3976	:  try
3977	:    return 4711
3978	:  finally
3979	:    echo "cleanup\n"
3980	:  endtry
3981	:  echo "Foo still active"
3982	:endfunction
3983	:
3984	:echo Foo() "returned by Foo"
3985
3986This displays "cleanup" and "4711 returned by Foo".  You don't need to add an
3987extra ":return" in the finally clause.  (Above all, this would override the
3988return value.)
3989
3990							*except-from-finally*
3991Using either of ":continue", ":break", ":return", ":finish", or ":throw" in
3992a finally clause is possible, but not recommended since it abandons the
3993cleanup actions for the try conditional.  But, of course, interrupt and error
3994exceptions might get raised from a finally clause.
3995   Example where an error in the finally clause stops an interrupt from
3996working correctly: >
3997
3998	:try
3999	:  try
4000	:    echo "Press CTRL-C for interrupt"
4001	:    while 1
4002	:    endwhile
4003	:  finally
4004	:    unlet novar
4005	:  endtry
4006	:catch /novar/
4007	:endtry
4008	:echo "Script still running"
4009	:sleep 1
4010
4011If you need to put commands that could fail into a finally clause, you should
4012think about catching or ignoring the errors in these commands, see
4013|catch-errors| and |ignore-errors|.
4014
4015
4016CATCHING ERRORS						*catch-errors*
4017
4018If you want to catch specific errors, you just have to put the code to be
4019watched in a try block and add a catch clause for the error message.  The
4020presence of the try conditional causes all errors to be converted to an
4021exception.  No message is displayed and |v:errmsg| is not set then.  To find
4022the right pattern for the ":catch" command, you have to know how the format of
4023the error exception is.
4024   Error exceptions have the following format: >
4025
4026	Vim({cmdname}):{errmsg}
4027or >
4028	Vim:{errmsg}
4029
4030{cmdname} is the name of the command that failed; the second form is used when
4031the command name is not known.  {errmsg} is the error message usually produced
4032when the error occurs outside try conditionals.  It always begins with
4033a capital "E", followed by a two or three-digit error number, a colon, and
4034a space.
4035
4036Examples:
4037
4038The command >
4039	:unlet novar
4040normally produces the error message >
4041	E108: No such variable: "novar"
4042which is converted inside try conditionals to an exception >
4043	Vim(unlet):E108: No such variable: "novar"
4044
4045The command >
4046	:dwim
4047normally produces the error message >
4048	E492: Not an editor command: dwim
4049which is converted inside try conditionals to an exception >
4050	Vim:E492: Not an editor command: dwim
4051
4052You can catch all ":unlet" errors by a >
4053	:catch /^Vim(unlet):/
4054or all errors for misspelled command names by a >
4055	:catch /^Vim:E492:/
4056
4057Some error messages may be produced by different commands: >
4058	:function nofunc
4059and >
4060	:delfunction nofunc
4061both produce the error message >
4062	E128: Function name must start with a capital: nofunc
4063which is converted inside try conditionals to an exception >
4064	Vim(function):E128: Function name must start with a capital: nofunc
4065or >
4066	Vim(delfunction):E128: Function name must start with a capital: nofunc
4067respectively.  You can catch the error by its number independently on the
4068command that caused it if you use the following pattern: >
4069	:catch /^Vim(\a\+):E128:/
4070
4071Some commands like >
4072	:let x = novar
4073produce multiple error messages, here: >
4074	E121: Undefined variable: novar
4075	E15: Invalid expression:  novar
4076Only the first is used for the exception value, since it is the most specific
4077one (see |except-several-errors|).  So you can catch it by >
4078	:catch /^Vim(\a\+):E121:/
4079
4080You can catch all errors related to the name "nofunc" by >
4081	:catch /\<nofunc\>/
4082
4083You can catch all Vim errors in the ":write" and ":read" commands by >
4084	:catch /^Vim(\(write\|read\)):E\d\+:/
4085
4086You can catch all Vim errors by the pattern >
4087	:catch /^Vim\((\a\+)\)\=:E\d\+:/
4088<
4089							*catch-text*
4090NOTE: You should never catch the error message text itself: >
4091	:catch /No such variable/
4092only works in the english locale, but not when the user has selected
4093a different language by the |:language| command.  It is however helpful to
4094cite the message text in a comment: >
4095	:catch /^Vim(\a\+):E108:/   " No such variable
4096
4097
4098IGNORING ERRORS						*ignore-errors*
4099
4100You can ignore errors in a specific Vim command by catching them locally: >
4101
4102	:try
4103	:  write
4104	:catch
4105	:endtry
4106
4107But you are strongly recommended NOT to use this simple form, since it could
4108catch more than you want.  With the ":write" command, some autocommands could
4109be executed and cause errors not related to writing, for instance: >
4110
4111	:au BufWritePre * unlet novar
4112
4113There could even be such errors you are not responsible for as a script
4114writer: a user of your script might have defined such autocommands.  You would
4115then hide the error from the user.
4116   It is much better to use >
4117
4118	:try
4119	:  write
4120	:catch /^Vim(write):/
4121	:endtry
4122
4123which only catches real write errors.  So catch only what you'd like to ignore
4124intentionally.
4125
4126For a single command that does not cause execution of autocommands, you could
4127even suppress the conversion of errors to exceptions by the ":silent!"
4128command: >
4129	:silent! nunmap k
4130This works also when a try conditional is active.
4131
4132
4133CATCHING INTERRUPTS					*catch-interrupt*
4134
4135When there are active try conditionals, an interrupt (CTRL-C) is converted to
4136the exception "Vim:Interrupt".  You can catch it like every exception.  The
4137script is not terminated, then.
4138   Example: >
4139
4140	:function! TASK1()
4141	:  sleep 10
4142	:endfunction
4143
4144	:function! TASK2()
4145	:  sleep 20
4146	:endfunction
4147
4148	:while 1
4149	:  let command = input("Type a command: ")
4150	:  try
4151	:    if command == ""
4152	:      continue
4153	:    elseif command == "END"
4154	:      break
4155	:    elseif command == "TASK1"
4156	:      call TASK1()
4157	:    elseif command == "TASK2"
4158	:      call TASK2()
4159	:    else
4160	:      echo "\nIllegal command:" command
4161	:      continue
4162	:    endif
4163	:  catch /^Vim:Interrupt$/
4164	:    echo "\nCommand interrupted"
4165	:    " Caught the interrupt.  Continue with next prompt.
4166	:  endtry
4167	:endwhile
4168
4169You can interrupt a task here by pressing CTRL-C; the script then asks for
4170a new command.  If you press CTRL-C at the prompt, the script is terminated.
4171
4172For testing what happens when CTRL-C would be pressed on a specific line in
4173your script, use the debug mode and execute the |>quit| or |>interrupt|
4174command on that line.  See |debug-scripts|.
4175
4176
4177CATCHING ALL						*catch-all*
4178
4179The commands >
4180
4181	:catch /.*/
4182	:catch //
4183	:catch
4184
4185catch everything, error exceptions, interrupt exceptions and exceptions
4186explicitly thrown by the |:throw| command.  This is useful at the top level of
4187a script in order to catch unexpected things.
4188   Example: >
4189
4190	:try
4191	:
4192	:  " do the hard work here
4193	:
4194	:catch /MyException/
4195	:
4196	:  " handle known problem
4197	:
4198	:catch /^Vim:Interrupt$/
4199	:    echo "Script interrupted"
4200	:catch /.*/
4201	:  echo "Internal error (" . v:exception . ")"
4202	:  echo " - occurred at " . v:throwpoint
4203	:endtry
4204	:" end of script
4205
4206Note: Catching all might catch more things than you want.  Thus, you are
4207strongly encouraged to catch only for problems that you can really handle by
4208specifying a pattern argument to the ":catch".
4209   Example: Catching all could make it nearly impossible to interrupt a script
4210by pressing CTRL-C: >
4211
4212	:while 1
4213	:  try
4214	:    sleep 1
4215	:  catch
4216	:  endtry
4217	:endwhile
4218
4219
4220EXCEPTIONS AND AUTOCOMMANDS				*except-autocmd*
4221
4222Exceptions may be used during execution of autocommands.  Example: >
4223
4224	:autocmd User x try
4225	:autocmd User x   throw "Oops!"
4226	:autocmd User x catch
4227	:autocmd User x   echo v:exception
4228	:autocmd User x endtry
4229	:autocmd User x throw "Arrgh!"
4230	:autocmd User x echo "Should not be displayed"
4231	:
4232	:try
4233	:  doautocmd User x
4234	:catch
4235	:  echo v:exception
4236	:endtry
4237
4238This displays "Oops!" and "Arrgh!".
4239
4240							*except-autocmd-Pre*
4241For some commands, autocommands get executed before the main action of the
4242command takes place.  If an exception is thrown and not caught in the sequence
4243of autocommands, the sequence and the command that caused its execution are
4244abandoned and the exception is propagated to the caller of the command.
4245   Example: >
4246
4247	:autocmd BufWritePre * throw "FAIL"
4248	:autocmd BufWritePre * echo "Should not be displayed"
4249	:
4250	:try
4251	:  write
4252	:catch
4253	:  echo "Caught:" v:exception "from" v:throwpoint
4254	:endtry
4255
4256Here, the ":write" command does not write the file currently being edited (as
4257you can see by checking 'modified'), since the exception from the BufWritePre
4258autocommand abandons the ":write".  The exception is then caught and the
4259script displays: >
4260
4261	Caught: FAIL from BufWrite Auto commands for "*"
4262<
4263							*except-autocmd-Post*
4264For some commands, autocommands get executed after the main action of the
4265command has taken place.  If this main action fails and the command is inside
4266an active try conditional, the autocommands are skipped and an error exception
4267is thrown that can be caught by the caller of the command.
4268   Example: >
4269
4270	:autocmd BufWritePost * echo "File successfully written!"
4271	:
4272	:try
4273	:  write /i/m/p/o/s/s/i/b/l/e
4274	:catch
4275	:  echo v:exception
4276	:endtry
4277
4278This just displays: >
4279
4280	Vim(write):E212: Can't open file for writing (/i/m/p/o/s/s/i/b/l/e)
4281
4282If you really need to execute the autocommands even when the main action
4283fails, trigger the event from the catch clause.
4284   Example: >
4285
4286	:autocmd BufWritePre  * set noreadonly
4287	:autocmd BufWritePost * set readonly
4288	:
4289	:try
4290	:  write /i/m/p/o/s/s/i/b/l/e
4291	:catch
4292	:  doautocmd BufWritePost /i/m/p/o/s/s/i/b/l/e
4293	:endtry
4294<
4295You can also use ":silent!": >
4296
4297	:let x = "ok"
4298	:let v:errmsg = ""
4299	:autocmd BufWritePost * if v:errmsg != ""
4300	:autocmd BufWritePost *   let x = "after fail"
4301	:autocmd BufWritePost * endif
4302	:try
4303	:  silent! write /i/m/p/o/s/s/i/b/l/e
4304	:catch
4305	:endtry
4306	:echo x
4307
4308This displays "after fail".
4309
4310If the main action of the command does not fail, exceptions from the
4311autocommands will be catchable by the caller of the command:  >
4312
4313	:autocmd BufWritePost * throw ":-("
4314	:autocmd BufWritePost * echo "Should not be displayed"
4315	:
4316	:try
4317	:  write
4318	:catch
4319	:  echo v:exception
4320	:endtry
4321<
4322							*except-autocmd-Cmd*
4323For some commands, the normal action can be replaced by a sequence of
4324autocommands.  Exceptions from that sequence will be catchable by the caller
4325of the command.
4326   Example:  For the ":write" command, the caller cannot know whether the file
4327had actually been written when the exception occurred.  You need to tell it in
4328some way. >
4329
4330	:if !exists("cnt")
4331	:  let cnt = 0
4332	:
4333	:  autocmd BufWriteCmd * if &modified
4334	:  autocmd BufWriteCmd *   let cnt = cnt + 1
4335	:  autocmd BufWriteCmd *   if cnt % 3 == 2
4336	:  autocmd BufWriteCmd *     throw "BufWriteCmdError"
4337	:  autocmd BufWriteCmd *   endif
4338	:  autocmd BufWriteCmd *   write | set nomodified
4339	:  autocmd BufWriteCmd *   if cnt % 3 == 0
4340	:  autocmd BufWriteCmd *     throw "BufWriteCmdError"
4341	:  autocmd BufWriteCmd *   endif
4342	:  autocmd BufWriteCmd *   echo "File successfully written!"
4343	:  autocmd BufWriteCmd * endif
4344	:endif
4345	:
4346	:try
4347	:	write
4348	:catch /^BufWriteCmdError$/
4349	:  if &modified
4350	:    echo "Error on writing (file contents not changed)"
4351	:  else
4352	:    echo "Error after writing"
4353	:  endif
4354	:catch /^Vim(write):/
4355	:    echo "Error on writing"
4356	:endtry
4357
4358When this script is sourced several times after making changes, it displays
4359first >
4360	File successfully written!
4361then >
4362	Error on writing (file contents not changed)
4363then >
4364	Error after writing
4365etc.
4366
4367							*except-autocmd-ill*
4368You cannot spread a try conditional over autocommands for different events.
4369The following code is ill-formed: >
4370
4371	:autocmd BufWritePre  * try
4372	:
4373	:autocmd BufWritePost * catch
4374	:autocmd BufWritePost *   echo v:exception
4375	:autocmd BufWritePost * endtry
4376	:
4377	:write
4378
4379
4380EXCEPTION HIERARCHIES AND PARAMETERIZED EXCEPTIONS	*except-hier-param*
4381
4382Some programming languages allow to use hierarchies of exception classes or to
4383pass additional information with the object of an exception class.  You can do
4384similar things in Vim.
4385   In order to throw an exception from a hierarchy, just throw the complete
4386class name with the components separated by a colon, for instance throw the
4387string "EXCEPT:MATHERR:OVERFLOW" for an overflow in a mathematical library.
4388   When you want to pass additional information with your exception class, add
4389it in parentheses, for instance throw the string "EXCEPT:IO:WRITEERR(myfile)"
4390for an error when writing "myfile".
4391   With the appropriate patterns in the ":catch" command, you can catch for
4392base classes or derived classes of your hierarchy.  Additional information in
4393parentheses can be cut out from |v:exception| with the ":substitute" command.
4394   Example: >
4395
4396	:function! CheckRange(a, func)
4397	:  if a:a < 0
4398	:    throw "EXCEPT:MATHERR:RANGE(" . a:func . ")"
4399	:  endif
4400	:endfunction
4401	:
4402	:function! Add(a, b)
4403	:  call CheckRange(a:a, "Add")
4404	:  call CheckRange(a:b, "Add")
4405	:  let c = a:a + a:b
4406	:  if c < 0
4407	:    throw "EXCEPT:MATHERR:OVERFLOW"
4408	:  endif
4409	:  return c
4410	:endfunction
4411	:
4412	:function! Div(a, b)
4413	:  call CheckRange(a:a, "Div")
4414	:  call CheckRange(a:b, "Div")
4415	:  if (a:b == 0)
4416	:    throw "EXCEPT:MATHERR:ZERODIV"
4417	:  endif
4418	:  return a:a / a:b
4419	:endfunction
4420	:
4421	:function! Write(file)
4422	:  try
4423	:    execute "write" a:file
4424	:  catch /^Vim(write):/
4425	:    throw "EXCEPT:IO(" . getcwd() . ", " . a:file . "):WRITEERR"
4426	:  endtry
4427	:endfunction
4428	:
4429	:try
4430	:
4431	:  " something with arithmetics and I/O
4432	:
4433	:catch /^EXCEPT:MATHERR:RANGE/
4434	:  let function = substitute(v:exception, '.*(\(\a\+\)).*', '\1', "")
4435	:  echo "Range error in" function
4436	:
4437	:catch /^EXCEPT:MATHERR/	" catches OVERFLOW and ZERODIV
4438	:  echo "Math error"
4439	:
4440	:catch /^EXCEPT:IO/
4441	:  let dir = substitute(v:exception, '.*(\(.\+\),\s*.\+).*', '\1', "")
4442	:  let file = substitute(v:exception, '.*(.\+,\s*\(.\+\)).*', '\1', "")
4443	:  if file !~ '^/'
4444	:    let file = dir . "/" . file
4445	:  endif
4446	:  echo 'I/O error for "' . file . '"'
4447	:
4448	:catch /^EXCEPT/
4449	:  echo "Unspecified error"
4450	:
4451	:endtry
4452
4453The exceptions raised by Vim itself (on error or when pressing CTRL-C) use
4454a flat hierarchy:  they are all in the "Vim" class.  You cannot throw yourself
4455exceptions with the "Vim" prefix; they are reserved for Vim.
4456   Vim error exceptions are parameterized with the name of the command that
4457failed, if known.  See |catch-errors|.
4458
4459
4460PECULIARITIES
4461							*except-compat*
4462The exception handling concept requires that the command sequence causing the
4463exception is aborted immediately and control is transferred to finally clauses
4464and/or a catch clause.
4465
4466In the Vim script language there are cases where scripts and functions
4467continue after an error: in functions without the "abort" flag or in a command
4468after ":silent!", control flow goes to the following line, and outside
4469functions, control flow goes to the line following the outermost ":endwhile"
4470or ":endif".  On the other hand, errors should be catchable as exceptions
4471(thus, requiring the immediate abortion).
4472
4473This problem has been solved by converting errors to exceptions and using
4474immediate abortion (if not suppressed by ":silent!") only when a try
4475conditional is active.  This is no restriction since an (error) exception can
4476be caught only from an active try conditional.  If you want an immediate
4477termination without catching the error, just use a try conditional without
4478catch clause.  (You can cause cleanup code being executed before termination
4479by specifying a finally clause.)
4480
4481When no try conditional is active, the usual abortion and continuation
4482behavior is used instead of immediate abortion.  This ensures compatibility of
4483scripts written for Vim 6.1 and earlier.
4484
4485However, when sourcing an existing script that does not use exception handling
4486commands (or when calling one of its functions) from inside an active try
4487conditional of a new script, you might change the control flow of the existing
4488script on error.  You get the immediate abortion on error and can catch the
4489error in the new script.  If however the sourced script suppresses error
4490messages by using the ":silent!" command (checking for errors by testing
4491|v:errmsg| if appropriate), its execution path is not changed.  The error is
4492not converted to an exception.  (See |:silent|.)  So the only remaining cause
4493where this happens is for scripts that don't care about errors and produce
4494error messages.  You probably won't want to use such code from your new
4495scripts.
4496
4497							*except-syntax-err*
4498Syntax errors in the exception handling commands are never caught by any of
4499the ":catch" commands of the try conditional they belong to.  Its finally
4500clauses, however, is executed.
4501   Example: >
4502
4503	:try
4504	:  try
4505	:    throw 4711
4506	:  catch /\(/
4507	:    echo "in catch with syntax error"
4508	:  catch
4509	:    echo "inner catch-all"
4510	:  finally
4511	:    echo "inner finally"
4512	:  endtry
4513	:catch
4514	:  echo 'outer catch-all caught "' . v:exception . '"'
4515	:  finally
4516	:    echo "outer finally"
4517	:endtry
4518
4519This displays: >
4520    inner finally
4521    outer catch-all caught "Vim(catch):E54: Unmatched \("
4522    outer finally
4523The original exception is discarded and an error exception is raised, instead.
4524
4525							*except-single-line*
4526The ":try", ":catch", ":finally", and ":endtry" commands can be put on
4527a single line, but then syntax errors may make it difficult to recognize the
4528"catch" line, thus you better avoid this.
4529   Example: >
4530	:try | unlet! foo # | catch | endtry
4531raises an error exception for the trailing characters after the ":unlet!"
4532argument, but does not see the ":catch" and ":endtry" commands, so that the
4533error exception is discarded and the "E488: Trailing characters" message gets
4534displayed.
4535
4536							*except-several-errors*
4537When several errors appear in a single command, the first error message is
4538usually the most specific one and therefor converted to the error exception.
4539   Example: >
4540	echo novar
4541causes >
4542	E121: Undefined variable: novar
4543	E15: Invalid expression: novar
4544The value of the error exception inside try conditionals is: >
4545	Vim(echo):E121: Undefined variable: novar
4546<							*except-syntax-error*
4547But when a syntax error is detected after a normal error in the same command,
4548the syntax error is used for the exception being thrown.
4549   Example: >
4550	unlet novar #
4551causes >
4552	E108: No such variable: "novar"
4553	E488: Trailing characters
4554The value of the error exception inside try conditionals is: >
4555	Vim(unlet):E488: Trailing characters
4556This is done because the syntax error might change the execution path in a way
4557not intended by the user.  Example: >
4558	try
4559	    try | unlet novar # | catch | echo v:exception | endtry
4560	catch /.*/
4561	    echo "outer catch:" v:exception
4562	endtry
4563This displays "outer catch: Vim(unlet):E488: Trailing characters", and then
4564a "E600: Missing :endtry" error message is given, see |except-single-line|.
4565
4566==============================================================================
45679. Examples						*eval-examples*
4568
4569Printing in Hex ~
4570>
4571  :" The function Nr2Hex() returns the Hex string of a number.
4572  :func Nr2Hex(nr)
4573  :  let n = a:nr
4574  :  let r = ""
4575  :  while n
4576  :    let r = '0123456789ABCDEF'[n % 16] . r
4577  :    let n = n / 16
4578  :  endwhile
4579  :  return r
4580  :endfunc
4581
4582  :" The function String2Hex() converts each character in a string to a two
4583  :" character Hex string.
4584  :func String2Hex(str)
4585  :  let out = ''
4586  :  let ix = 0
4587  :  while ix < strlen(a:str)
4588  :    let out = out . Nr2Hex(char2nr(a:str[ix]))
4589  :    let ix = ix + 1
4590  :  endwhile
4591  :  return out
4592  :endfunc
4593
4594Example of its use: >
4595  :echo Nr2Hex(32)
4596result: "20" >
4597  :echo String2Hex("32")
4598result: "3332"
4599
4600
4601Sorting lines (by Robert Webb) ~
4602
4603Here is a Vim script to sort lines.  Highlight the lines in Vim and type
4604":Sort".  This doesn't call any external programs so it'll work on any
4605platform.  The function Sort() actually takes the name of a comparison
4606function as its argument, like qsort() does in C.  So you could supply it
4607with different comparison functions in order to sort according to date etc.
4608>
4609  :" Function for use with Sort(), to compare two strings.
4610  :func! Strcmp(str1, str2)
4611  :  if (a:str1 < a:str2)
4612  :	return -1
4613  :  elseif (a:str1 > a:str2)
4614  :	return 1
4615  :  else
4616  :	return 0
4617  :  endif
4618  :endfunction
4619
4620  :" Sort lines.  SortR() is called recursively.
4621  :func! SortR(start, end, cmp)
4622  :  if (a:start >= a:end)
4623  :	return
4624  :  endif
4625  :  let partition = a:start - 1
4626  :  let middle = partition
4627  :  let partStr = getline((a:start + a:end) / 2)
4628  :  let i = a:start
4629  :  while (i <= a:end)
4630  :	let str = getline(i)
4631  :	exec "let result = " . a:cmp . "(str, partStr)"
4632  :	if (result <= 0)
4633  :	    " Need to put it before the partition.  Swap lines i and partition.
4634  :	    let partition = partition + 1
4635  :	    if (result == 0)
4636  :		let middle = partition
4637  :	    endif
4638  :	    if (i != partition)
4639  :		let str2 = getline(partition)
4640  :		call setline(i, str2)
4641  :		call setline(partition, str)
4642  :	    endif
4643  :	endif
4644  :	let i = i + 1
4645  :  endwhile
4646
4647  :  " Now we have a pointer to the "middle" element, as far as partitioning
4648  :  " goes, which could be anywhere before the partition.  Make sure it is at
4649  :  " the end of the partition.
4650  :  if (middle != partition)
4651  :	let str = getline(middle)
4652  :	let str2 = getline(partition)
4653  :	call setline(middle, str2)
4654  :	call setline(partition, str)
4655  :  endif
4656  :  call SortR(a:start, partition - 1, a:cmp)
4657  :  call SortR(partition + 1, a:end, a:cmp)
4658  :endfunc
4659
4660  :" To Sort a range of lines, pass the range to Sort() along with the name of a
4661  :" function that will compare two lines.
4662  :func! Sort(cmp) range
4663  :  call SortR(a:firstline, a:lastline, a:cmp)
4664  :endfunc
4665
4666  :" :Sort takes a range of lines and sorts them.
4667  :command! -nargs=0 -range Sort <line1>,<line2>call Sort("Strcmp")
4668<
4669							*sscanf*
4670There is no sscanf() function in Vim.  If you need to extract parts from a
4671line, you can use matchstr() and substitute() to do it.  This example shows
4672how to get the file name, line number and column number out of a line like
4673"foobar.txt, 123, 45". >
4674   :" Set up the match bit
4675   :let mx='\(\f\+\),\s*\(\d\+\),\s*\(\d\+\)'
4676   :"get the part matching the whole expression
4677   :let l = matchstr(line, mx)
4678   :"get each item out of the match
4679   :let file = substitute(l, mx, '\1', '')
4680   :let lnum = substitute(l, mx, '\2', '')
4681   :let col = substitute(l, mx, '\3', '')
4682
4683The input is in the variable "line", the results in the variables "file",
4684"lnum" and "col". (idea from Michael Geddes)
4685
4686==============================================================================
468710. No +eval feature				*no-eval-feature*
4688
4689When the |+eval| feature was disabled at compile time, none of the expression
4690evaluation commands are available.  To prevent this from causing Vim scripts
4691to generate all kinds of errors, the ":if" and ":endif" commands are still
4692recognized, though the argument of the ":if" and everything between the ":if"
4693and the matching ":endif" is ignored.  Nesting of ":if" blocks is allowed, but
4694only if the commands are at the start of the line.  The ":else" command is not
4695recognized.
4696
4697Example of how to avoid executing commands when the |+eval| feature is
4698missing: >
4699
4700	:if 1
4701	:  echo "Expression evaluation is compiled in"
4702	:else
4703	:  echo "You will _never_ see this message"
4704	:endif
4705
4706==============================================================================
470711. The sandbox					*eval-sandbox* *sandbox* *E48*
4708
4709The 'foldexpr', 'includeexpr', 'indentexpr', 'statusline' and 'foldtext'
4710options are evaluated in a sandbox.  This means that you are protected from
4711these expressions having nasty side effects.  This gives some safety for when
4712these options are set from a modeline.  It is also used when the command from
4713a tags file is executed.
4714This is not guaranteed 100% secure, but it should block most attacks.
4715
4716These items are not allowed in the sandbox:
4717	- changing the buffer text
4718	- defining or changing mapping, autocommands, functions, user commands
4719	- setting certain options (see |option-summary|)
4720	- executing a shell command
4721	- reading or writing a file
4722	- jumping to another buffer or editing a file
4723
4724 vim:tw=78:ts=8:ft=help:norl:
4725