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Bram Moolenaar843ee412004-06-30 16:16:41 +00001*eval.txt* For Vim version 7.0aa. Last change: 2004 Jun 30
Bram Moolenaar071d4272004-06-13 20:20:40 +00002
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
Bram Moolenaar69a7cb42004-06-20 12:51:53 +0000518script variables is set to the script where the function or command was
Bram Moolenaar071d4272004-06-13 20:20:40 +0000519defined.
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
Bram Moolenaar843ee412004-06-30 16:16:41 +0000682 *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
Bram Moolenaar071d4272004-06-13 20:20:40 +0000689 *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}
817char2nr( {expr}) Number ASCII value of first char in {expr}
818cindent( {lnum}) Number C indent for line {lnum}
819col( {expr}) Number column nr of cursor or mark
820confirm( {msg} [, {choices} [, {default} [, {type}]]])
821 Number number of choice picked by user
822cscope_connection( [{num} , {dbpath} [, {prepend}]])
823 Number checks existence of cscope connection
824cursor( {lnum}, {col}) Number position cursor at {lnum}, {col}
825delete( {fname}) Number delete file {fname}
826did_filetype() Number TRUE if FileType autocommand event used
827escape( {string}, {chars}) String escape {chars} in {string} with '\'
828eventhandler( ) Number TRUE if inside an event handler
829executable( {expr}) Number 1 if executable {expr} exists
830exists( {expr}) Number TRUE if {expr} exists
831expand( {expr}) String expand special keywords in {expr}
832filereadable( {file}) Number TRUE if {file} is a readable file
833filewritable( {file}) Number TRUE if {file} is a writable file
834fnamemodify( {fname}, {mods}) String modify file name
835foldclosed( {lnum}) Number first line of fold at {lnum} if closed
836foldclosedend( {lnum}) Number last line of fold at {lnum} if closed
837foldlevel( {lnum}) Number fold level at {lnum}
838foldtext( ) String line displayed for closed fold
839foreground( ) Number bring the Vim window to the foreground
840getchar( [expr]) Number get one character from the user
841getcharmod( ) Number modifiers for the last typed character
842getbufvar( {expr}, {varname}) variable {varname} in buffer {expr}
843getcmdline() String return the current command-line
844getcmdpos() Number return cursor position in command-line
845getcwd() String the current working directory
846getfsize( {fname}) Number size in bytes of file
847getftime( {fname}) Number last modification time of file
848getline( {lnum}) String line {lnum} from current buffer
849getreg( [{regname}]) String contents of register
850getregtype( [{regname}]) String type of register
851getwinposx() Number X coord in pixels of GUI Vim window
852getwinposy() Number Y coord in pixels of GUI Vim window
853getwinvar( {nr}, {varname}) variable {varname} in window {nr}
854glob( {expr}) String expand file wildcards in {expr}
855globpath( {path}, {expr}) String do glob({expr}) for all dirs in {path}
856has( {feature}) Number TRUE if feature {feature} supported
857hasmapto( {what} [, {mode}]) Number TRUE if mapping to {what} exists
858histadd( {history},{item}) String add an item to a history
859histdel( {history} [, {item}]) String remove an item from a history
860histget( {history} [, {index}]) String get the item {index} from a history
861histnr( {history}) Number highest index of a history
862hlexists( {name}) Number TRUE if highlight group {name} exists
863hlID( {name}) Number syntax ID of highlight group {name}
864hostname() String name of the machine Vim is running on
865iconv( {expr}, {from}, {to}) String convert encoding of {expr}
866indent( {lnum}) Number indent of line {lnum}
867input( {prompt} [, {text}]) String get input from the user
868inputdialog( {p} [, {t} [, {c}]]) String like input() but in a GUI dialog
869inputrestore() Number restore typeahead
870inputsave() Number save and clear typeahead
871inputsecret( {prompt} [, {text}]) String like input() but hiding the text
872isdirectory( {directory}) Number TRUE if {directory} is a directory
873libcall( {lib}, {func}, {arg}) String call {func} in library {lib} with {arg}
874libcallnr( {lib}, {func}, {arg}) Number idem, but return a Number
875line( {expr}) Number line nr of cursor, last line or mark
876line2byte( {lnum}) Number byte count of line {lnum}
877lispindent( {lnum}) Number Lisp indent for line {lnum}
878localtime() Number current time
879maparg( {name}[, {mode}]) String rhs of mapping {name} in mode {mode}
880mapcheck( {name}[, {mode}]) String check for mappings matching {name}
881match( {expr}, {pat}[, {start}])
882 Number position where {pat} matches in {expr}
883matchend( {expr}, {pat}[, {start}])
884 Number position where {pat} ends in {expr}
885matchstr( {expr}, {pat}[, {start}])
886 String match of {pat} in {expr}
887mode() String current editing mode
888nextnonblank( {lnum}) Number line nr of non-blank line >= {lnum}
889nr2char( {expr}) String single char with ASCII value {expr}
890prevnonblank( {lnum}) Number line nr of non-blank line <= {lnum}
891remote_expr( {server}, {string} [, {idvar}])
892 String send expression
893remote_foreground( {server}) Number bring Vim server to the foreground
894remote_peek( {serverid} [, {retvar}])
895 Number check for reply string
896remote_read( {serverid}) String read reply string
897remote_send( {server}, {string} [, {idvar}])
898 String send key sequence
899rename( {from}, {to}) Number rename (move) file from {from} to {to}
900resolve( {filename}) String get filename a shortcut points to
901search( {pattern} [, {flags}]) Number search for {pattern}
902searchpair( {start}, {middle}, {end} [, {flags} [, {skip}]])
903 Number search for other end of start/end pair
904server2client( {clientid}, {string})
905 Number send reply string
906serverlist() String get a list of available servers
907setbufvar( {expr}, {varname}, {val}) set {varname} in buffer {expr} to {val}
908setcmdpos( {pos}) Number set cursor position in command-line
909setline( {lnum}, {line}) Number set line {lnum} to {line}
910setreg( {n}, {v}[, {opt}]) Number set register to value and type
911setwinvar( {nr}, {varname}, {val}) set {varname} in window {nr} to {val}
912simplify( {filename}) String simplify filename as much as possible
913strftime( {format}[, {time}]) String time in specified format
914stridx( {haystack}, {needle}) Number first index of {needle} in {haystack}
915strlen( {expr}) Number length of the String {expr}
916strpart( {src}, {start}[, {len}])
917 String {len} characters of {src} at {start}
918strridx( {haystack}, {needle}) Number last index of {needle} in {haystack}
919strtrans( {expr}) String translate string to make it printable
920submatch( {nr}) String specific match in ":substitute"
921substitute( {expr}, {pat}, {sub}, {flags})
922 String all {pat} in {expr} replaced with {sub}
923synID( {line}, {col}, {trans}) Number syntax ID at {line} and {col}
924synIDattr( {synID}, {what} [, {mode}])
925 String attribute {what} of syntax ID {synID}
926synIDtrans( {synID}) Number translated syntax ID of {synID}
927system( {expr}) String output of shell command {expr}
928tempname() String name for a temporary file
929tolower( {expr}) String the String {expr} switched to lowercase
930toupper( {expr}) String the String {expr} switched to uppercase
931type( {name}) Number type of variable {name}
932virtcol( {expr}) Number screen column of cursor or mark
933visualmode( [expr]) String last visual mode used
934winbufnr( {nr}) Number buffer number of window {nr}
935wincol() Number window column of the cursor
936winheight( {nr}) Number height of window {nr}
937winline() Number window line of the cursor
938winnr() Number number of current window
939winrestcmd() String returns command to restore window sizes
940winwidth( {nr}) Number width of window {nr}
941
942append({lnum}, {string}) *append()*
943 Append the text {string} after line {lnum} in the current
944 buffer. {lnum} can be zero, to insert a line before the first
945 one. Returns 1 for failure ({lnum} out of range) or 0 for
946 success.
947
948 *argc()*
949argc() The result is the number of files in the argument list of the
950 current window. See |arglist|.
951
952 *argidx()*
953argidx() The result is the current index in the argument list. 0 is
954 the first file. argc() - 1 is the last one. See |arglist|.
955
956 *argv()*
957argv({nr}) The result is the {nr}th file in the argument list of the
958 current window. See |arglist|. "argv(0)" is the first one.
959 Example: >
960 :let i = 0
961 :while i < argc()
962 : let f = escape(argv(i), '. ')
963 : exe 'amenu Arg.' . f . ' :e ' . f . '<CR>'
964 : let i = i + 1
965 :endwhile
966<
967 *browse()*
968browse({save}, {title}, {initdir}, {default})
969 Put up a file requester. This only works when "has("browse")"
970 returns non-zero (only in some GUI versions).
971 The input fields are:
972 {save} when non-zero, select file to write
973 {title} title for the requester
974 {initdir} directory to start browsing in
975 {default} default file name
976 When the "Cancel" button is hit, something went wrong, or
977 browsing is not possible, an empty string is returned.
978
979bufexists({expr}) *bufexists()*
980 The result is a Number, which is non-zero if a buffer called
981 {expr} exists.
Bram Moolenaar69a7cb42004-06-20 12:51:53 +0000982 If the {expr} argument is a number, buffer numbers are used.
Bram Moolenaar071d4272004-06-13 20:20:40 +0000983 If the {expr} argument is a string it must match a buffer name
Bram Moolenaar69a7cb42004-06-20 12:51:53 +0000984 exactly. The name can be:
985 - Relative to the current directory.
986 - A full path.
987 - The name of a buffer with 'filetype' set to "nofile".
988 - A URL name.
Bram Moolenaar071d4272004-06-13 20:20:40 +0000989 Unlisted buffers will be found.
990 Note that help files are listed by their short name in the
991 output of |:buffers|, but bufexists() requires using their
992 long name to be able to find them.
993 Use "bufexists(0)" to test for the existence of an alternate
994 file name.
995 *buffer_exists()*
996 Obsolete name: buffer_exists().
997
998buflisted({expr}) *buflisted()*
999 The result is a Number, which is non-zero if a buffer called
1000 {expr} exists and is listed (has the 'buflisted' option set).
Bram Moolenaar69a7cb42004-06-20 12:51:53 +00001001 The {expr} argument is used like with |bufexists()|.
Bram Moolenaar071d4272004-06-13 20:20:40 +00001002
1003bufloaded({expr}) *bufloaded()*
1004 The result is a Number, which is non-zero if a buffer called
1005 {expr} exists and is loaded (shown in a window or hidden).
Bram Moolenaar69a7cb42004-06-20 12:51:53 +00001006 The {expr} argument is used like with |bufexists()|.
Bram Moolenaar071d4272004-06-13 20:20:40 +00001007
1008bufname({expr}) *bufname()*
1009 The result is the name of a buffer, as it is displayed by the
1010 ":ls" command.
1011 If {expr} is a Number, that buffer number's name is given.
1012 Number zero is the alternate buffer for the current window.
1013 If {expr} is a String, it is used as a |file-pattern| to match
1014 with the buffer names. This is always done like 'magic' is
1015 set and 'cpoptions' is empty. When there is more than one
1016 match an empty string is returned.
1017 "" or "%" can be used for the current buffer, "#" for the
1018 alternate buffer.
1019 A full match is preferred, otherwise a match at the start, end
1020 or middle of the buffer name is accepted.
1021 Listed buffers are found first. If there is a single match
1022 with a listed buffer, that one is returned. Next unlisted
1023 buffers are searched for.
1024 If the {expr} is a String, but you want to use it as a buffer
1025 number, force it to be a Number by adding zero to it: >
1026 :echo bufname("3" + 0)
1027< If the buffer doesn't exist, or doesn't have a name, an empty
1028 string is returned. >
1029 bufname("#") alternate buffer name
1030 bufname(3) name of buffer 3
1031 bufname("%") name of current buffer
1032 bufname("file2") name of buffer where "file2" matches.
1033< *buffer_name()*
1034 Obsolete name: buffer_name().
1035
1036 *bufnr()*
1037bufnr({expr}) The result is the number of a buffer, as it is displayed by
1038 the ":ls" command. For the use of {expr}, see |bufname()|
1039 above. If the buffer doesn't exist, -1 is returned.
1040 bufnr("$") is the last buffer: >
1041 :let last_buffer = bufnr("$")
1042< The result is a Number, which is the highest buffer number
1043 of existing buffers. Note that not all buffers with a smaller
1044 number necessarily exist, because ":bwipeout" may have removed
1045 them. Use bufexists() to test for the existence of a buffer.
1046 *buffer_number()*
1047 Obsolete name: buffer_number().
1048 *last_buffer_nr()*
1049 Obsolete name for bufnr("$"): last_buffer_nr().
1050
1051bufwinnr({expr}) *bufwinnr()*
1052 The result is a Number, which is the number of the first
1053 window associated with buffer {expr}. For the use of {expr},
1054 see |bufname()| above. If buffer {expr} doesn't exist or
1055 there is no such window, -1 is returned. Example: >
1056
1057 echo "A window containing buffer 1 is " . (bufwinnr(1))
1058
1059< The number can be used with |CTRL-W_w| and ":wincmd w"
1060 |:wincmd|.
1061
1062
1063byte2line({byte}) *byte2line()*
1064 Return the line number that contains the character at byte
1065 count {byte} in the current buffer. This includes the
1066 end-of-line character, depending on the 'fileformat' option
1067 for the current buffer. The first character has byte count
1068 one.
1069 Also see |line2byte()|, |go| and |:goto|.
1070 {not available when compiled without the |+byte_offset|
1071 feature}
1072
1073char2nr({expr}) *char2nr()*
1074 Return number value of the first char in {expr}. Examples: >
1075 char2nr(" ") returns 32
1076 char2nr("ABC") returns 65
1077< The current 'encoding' is used. Example for "utf-8": >
1078 char2nr("á") returns 225
1079 char2nr("á"[0]) returns 195
1080
1081cindent({lnum}) *cindent()*
1082 Get the amount of indent for line {lnum} according the C
1083 indenting rules, as with 'cindent'.
1084 The indent is counted in spaces, the value of 'tabstop' is
1085 relevant. {lnum} is used just like in |getline()|.
1086 When {lnum} is invalid or Vim was not compiled the |+cindent|
1087 feature, -1 is returned.
1088
1089 *col()*
1090col({expr}) The result is a Number, which is the column of the file
1091 position given with {expr}. The accepted positions are:
1092 . the cursor position
1093 $ the end of the cursor line (the result is the
1094 number of characters in the cursor line plus one)
1095 'x position of mark x (if the mark is not set, 0 is
1096 returned)
1097 For the screen column position use |virtcol()|.
1098 Note that only marks in the current file can be used.
1099 Examples: >
1100 col(".") column of cursor
1101 col("$") length of cursor line plus one
1102 col("'t") column of mark t
1103 col("'" . markname) column of mark markname
1104< The first column is 1. 0 is returned for an error.
1105 For the cursor position, when 'virtualedit' is active, the
1106 column is one higher if the cursor is after the end of the
1107 line. This can be used to obtain the column in Insert mode: >
1108 :imap <F2> <C-O>:let save_ve = &ve<CR>
1109 \<C-O>:set ve=all<CR>
1110 \<C-O>:echo col(".") . "\n" <Bar>
1111 \let &ve = save_ve<CR>
1112<
1113 *confirm()*
1114confirm({msg} [, {choices} [, {default} [, {type}]]])
1115 Confirm() offers the user a dialog, from which a choice can be
1116 made. It returns the number of the choice. For the first
1117 choice this is 1.
1118 Note: confirm() is only supported when compiled with dialog
1119 support, see |+dialog_con| and |+dialog_gui|.
1120 {msg} is displayed in a |dialog| with {choices} as the
1121 alternatives. When {choices} is missing or empty, "&OK" is
1122 used (and translated).
1123 {msg} is a String, use '\n' to include a newline. Only on
1124 some systems the string is wrapped when it doesn't fit.
1125 {choices} is a String, with the individual choices separated
1126 by '\n', e.g. >
1127 confirm("Save changes?", "&Yes\n&No\n&Cancel")
1128< The letter after the '&' is the shortcut key for that choice.
1129 Thus you can type 'c' to select "Cancel". The shortcut does
1130 not need to be the first letter: >
1131 confirm("file has been modified", "&Save\nSave &All")
1132< For the console, the first letter of each choice is used as
1133 the default shortcut key.
1134 The optional {default} argument is the number of the choice
1135 that is made if the user hits <CR>. Use 1 to make the first
1136 choice the default one. Use 0 to not set a default. If
1137 {default} is omitted, 1 is used.
1138 The optional {type} argument gives the type of dialog. This
1139 is only used for the icon of the Win32 GUI. It can be one of
1140 these values: "Error", "Question", "Info", "Warning" or
1141 "Generic". Only the first character is relevant. When {type}
1142 is omitted, "Generic" is used.
1143 If the user aborts the dialog by pressing <Esc>, CTRL-C,
1144 or another valid interrupt key, confirm() returns 0.
1145
1146 An example: >
1147 :let choice = confirm("What do you want?", "&Apples\n&Oranges\n&Bananas", 2)
1148 :if choice == 0
1149 : echo "make up your mind!"
1150 :elseif choice == 3
1151 : echo "tasteful"
1152 :else
1153 : echo "I prefer bananas myself."
1154 :endif
1155< In a GUI dialog, buttons are used. The layout of the buttons
1156 depends on the 'v' flag in 'guioptions'. If it is included,
1157 the buttons are always put vertically. Otherwise, confirm()
1158 tries to put the buttons in one horizontal line. If they
1159 don't fit, a vertical layout is used anyway. For some systems
1160 the horizontal layout is always used.
1161
1162 *cscope_connection()*
1163cscope_connection([{num} , {dbpath} [, {prepend}]])
1164 Checks for the existence of a |cscope| connection. If no
1165 parameters are specified, then the function returns:
1166 0, if cscope was not available (not compiled in), or
1167 if there are no cscope connections;
1168 1, if there is at least one cscope connection.
1169
1170 If parameters are specified, then the value of {num}
1171 determines how existence of a cscope connection is checked:
1172
1173 {num} Description of existence check
1174 ----- ------------------------------
1175 0 Same as no parameters (e.g., "cscope_connection()").
1176 1 Ignore {prepend}, and use partial string matches for
1177 {dbpath}.
1178 2 Ignore {prepend}, and use exact string matches for
1179 {dbpath}.
1180 3 Use {prepend}, use partial string matches for both
1181 {dbpath} and {prepend}.
1182 4 Use {prepend}, use exact string matches for both
1183 {dbpath} and {prepend}.
1184
1185 Note: All string comparisons are case sensitive!
1186
1187 Examples. Suppose we had the following (from ":cs show"): >
1188
1189 # pid database name prepend path
1190 0 27664 cscope.out /usr/local
1191<
1192 Invocation Return Val ~
1193 ---------- ---------- >
1194 cscope_connection() 1
1195 cscope_connection(1, "out") 1
1196 cscope_connection(2, "out") 0
1197 cscope_connection(3, "out") 0
1198 cscope_connection(3, "out", "local") 1
1199 cscope_connection(4, "out") 0
1200 cscope_connection(4, "out", "local") 0
1201 cscope_connection(4, "cscope.out", "/usr/local") 1
1202<
1203cursor({lnum}, {col}) *cursor()*
1204 Positions the cursor at the column {col} in the line {lnum}.
1205 Does not change the jumplist.
1206 If {lnum} is greater than the number of lines in the buffer,
1207 the cursor will be positioned at the last line in the buffer.
1208 If {lnum} is zero, the cursor will stay in the current line.
1209 If {col} is greater than the number of characters in the line,
1210 the cursor will be positioned at the last character in the
1211 line.
1212 If {col} is zero, the cursor will stay in the current column.
1213
1214 *delete()*
1215delete({fname}) Deletes the file by the name {fname}. The result is a Number,
1216 which is 0 if the file was deleted successfully, and non-zero
1217 when the deletion failed.
1218
1219 *did_filetype()*
1220did_filetype() Returns non-zero when autocommands are being executed and the
1221 FileType event has been triggered at least once. Can be used
1222 to avoid triggering the FileType event again in the scripts
1223 that detect the file type. |FileType|
1224 When editing another file, the counter is reset, thus this
1225 really checks if the FileType event has been triggered for the
1226 current buffer. This allows an autocommand that starts
1227 editing another buffer to set 'filetype' and load a syntax
1228 file.
1229
1230escape({string}, {chars}) *escape()*
1231 Escape the characters in {chars} that occur in {string} with a
1232 backslash. Example: >
1233 :echo escape('c:\program files\vim', ' \')
1234< results in: >
1235 c:\\program\ files\\vim
1236<
1237eventhandler() *eventhandler()*
1238 Returns 1 when inside an event handler. That is that Vim got
1239 interrupted while waiting for the user to type a character,
1240 e.g., when dropping a file on Vim. This means interactive
1241 commands cannot be used. Otherwise zero is returned.
1242
1243executable({expr}) *executable()*
1244 This function checks if an executable with the name {expr}
1245 exists. {expr} must be the name of the program without any
Bram Moolenaarf4b8e572004-06-24 15:53:16 +00001246 arguments.
1247 executable() uses the value of $PATH and/or the normal
1248 searchpath for programs. *PATHEXT*
1249 On MS-DOS and MS-Windows the ".exe", ".bat", etc. can
1250 optionally be included. Then the extensions in $PATHEXT are
1251 tried. Thus if "foo.exe" does not exist, "foo.exe.bat" can be
1252 found. If $PATHEXT is not set then ".exe;.com;.bat;.cmd" is
1253 used. A dot by itself can be used in $PATHEXT to try using
1254 the name without an extension. When 'shell' looks like a
1255 Unix shell, then the name is also tried without adding an
1256 extension.
1257 On MS-DOS and MS-Windows it only checks if the file exists and
1258 is not a directory, not if it's really executable.
Bram Moolenaar071d4272004-06-13 20:20:40 +00001259 The result is a Number:
1260 1 exists
1261 0 does not exist
1262 -1 not implemented on this system
1263
1264 *exists()*
1265exists({expr}) The result is a Number, which is non-zero if {expr} is
1266 defined, zero otherwise. The {expr} argument is a string,
1267 which contains one of these:
1268 &option-name Vim option (only checks if it exists,
1269 not if it really works)
1270 +option-name Vim option that works.
1271 $ENVNAME environment variable (could also be
1272 done by comparing with an empty
1273 string)
1274 *funcname built-in function (see |functions|)
1275 or user defined function (see
1276 |user-functions|).
1277 varname internal variable (see
1278 |internal-variables|). Does not work
1279 for |curly-braces-names|.
1280 :cmdname Ex command: built-in command, user
1281 command or command modifier |:command|.
1282 Returns:
1283 1 for match with start of a command
1284 2 full match with a command
1285 3 matches several user commands
1286 To check for a supported command
1287 always check the return value to be 2.
1288 #event autocommand defined for this event
1289 #event#pattern autocommand defined for this event and
1290 pattern (the pattern is taken
1291 literally and compared to the
1292 autocommand patterns character by
1293 character)
1294 For checking for a supported feature use |has()|.
1295
1296 Examples: >
1297 exists("&shortname")
1298 exists("$HOSTNAME")
1299 exists("*strftime")
1300 exists("*s:MyFunc")
1301 exists("bufcount")
1302 exists(":Make")
1303 exists("#CursorHold");
1304 exists("#BufReadPre#*.gz")
1305< There must be no space between the symbol (&/$/*/#) and the
1306 name.
1307 Note that the argument must be a string, not the name of the
1308 variable itself! For example: >
1309 exists(bufcount)
1310< This doesn't check for existence of the "bufcount" variable,
1311 but gets the contents of "bufcount", and checks if that
1312 exists.
1313
1314expand({expr} [, {flag}]) *expand()*
1315 Expand wildcards and the following special keywords in {expr}.
1316 The result is a String.
1317
1318 When there are several matches, they are separated by <NL>
1319 characters. [Note: in version 5.0 a space was used, which
1320 caused problems when a file name contains a space]
1321
1322 If the expansion fails, the result is an empty string. A name
1323 for a non-existing file is not included.
1324
1325 When {expr} starts with '%', '#' or '<', the expansion is done
1326 like for the |cmdline-special| variables with their associated
1327 modifiers. Here is a short overview:
1328
1329 % current file name
1330 # alternate file name
1331 #n alternate file name n
1332 <cfile> file name under the cursor
1333 <afile> autocmd file name
1334 <abuf> autocmd buffer number (as a String!)
1335 <amatch> autocmd matched name
1336 <sfile> sourced script file name
1337 <cword> word under the cursor
1338 <cWORD> WORD under the cursor
1339 <client> the {clientid} of the last received
1340 message |server2client()|
1341 Modifiers:
1342 :p expand to full path
1343 :h head (last path component removed)
1344 :t tail (last path component only)
1345 :r root (one extension removed)
1346 :e extension only
1347
1348 Example: >
1349 :let &tags = expand("%:p:h") . "/tags"
1350< Note that when expanding a string that starts with '%', '#' or
1351 '<', any following text is ignored. This does NOT work: >
1352 :let doesntwork = expand("%:h.bak")
1353< Use this: >
1354 :let doeswork = expand("%:h") . ".bak"
1355< Also note that expanding "<cfile>" and others only returns the
1356 referenced file name without further expansion. If "<cfile>"
1357 is "~/.cshrc", you need to do another expand() to have the
1358 "~/" expanded into the path of the home directory: >
1359 :echo expand(expand("<cfile>"))
1360<
1361 There cannot be white space between the variables and the
1362 following modifier. The |fnamemodify()| function can be used
1363 to modify normal file names.
1364
1365 When using '%' or '#', and the current or alternate file name
1366 is not defined, an empty string is used. Using "%:p" in a
1367 buffer with no name, results in the current directory, with a
1368 '/' added.
1369
1370 When {expr} does not start with '%', '#' or '<', it is
1371 expanded like a file name is expanded on the command line.
1372 'suffixes' and 'wildignore' are used, unless the optional
1373 {flag} argument is given and it is non-zero. Names for
1374 non-existing files are included.
1375
1376 Expand() can also be used to expand variables and environment
1377 variables that are only known in a shell. But this can be
1378 slow, because a shell must be started. See |expr-env-expand|.
1379 The expanded variable is still handled like a list of file
1380 names. When an environment variable cannot be expanded, it is
1381 left unchanged. Thus ":echo expand('$FOOBAR')" results in
1382 "$FOOBAR".
1383
1384 See |glob()| for finding existing files. See |system()| for
1385 getting the raw output of an external command.
1386
1387filereadable({file}) *filereadable()*
1388 The result is a Number, which is TRUE when a file with the
1389 name {file} exists, and can be read. If {file} doesn't exist,
1390 or is a directory, the result is FALSE. {file} is any
1391 expression, which is used as a String.
1392 *file_readable()*
1393 Obsolete name: file_readable().
1394
1395filewritable({file}) *filewritable()*
1396 The result is a Number, which is 1 when a file with the
1397 name {file} exists, and can be written. If {file} doesn't
1398 exist, or is not writable, the result is 0. If (file) is a
1399 directory, and we can write to it, the result is 2.
1400
1401fnamemodify({fname}, {mods}) *fnamemodify()*
1402 Modify file name {fname} according to {mods}. {mods} is a
1403 string of characters like it is used for file names on the
1404 command line. See |filename-modifiers|.
1405 Example: >
1406 :echo fnamemodify("main.c", ":p:h")
1407< results in: >
1408 /home/mool/vim/vim/src
1409< Note: Environment variables and "~" don't work in {fname}, use
1410 |expand()| first then.
1411
1412foldclosed({lnum}) *foldclosed()*
1413 The result is a Number. If the line {lnum} is in a closed
1414 fold, the result is the number of the first line in that fold.
1415 If the line {lnum} is not in a closed fold, -1 is returned.
1416
1417foldclosedend({lnum}) *foldclosedend()*
1418 The result is a Number. If the line {lnum} is in a closed
1419 fold, the result is the number of the last line in that fold.
1420 If the line {lnum} is not in a closed fold, -1 is returned.
1421
1422foldlevel({lnum}) *foldlevel()*
1423 The result is a Number, which is the foldlevel of line {lnum}
1424 in the current buffer. For nested folds the deepest level is
1425 returned. If there is no fold at line {lnum}, zero is
1426 returned. It doesn't matter if the folds are open or closed.
1427 When used while updating folds (from 'foldexpr') -1 is
1428 returned for lines where folds are still to be updated and the
1429 foldlevel is unknown. As a special case the level of the
1430 previous line is usually available.
1431
1432 *foldtext()*
1433foldtext() Returns a String, to be displayed for a closed fold. This is
1434 the default function used for the 'foldtext' option and should
1435 only be called from evaluating 'foldtext'. It uses the
1436 |v:foldstart|, |v:foldend| and |v:folddashes| variables.
1437 The returned string looks like this: >
1438 +-- 45 lines: abcdef
1439< The number of dashes depends on the foldlevel. The "45" is
1440 the number of lines in the fold. "abcdef" is the text in the
1441 first non-blank line of the fold. Leading white space, "//"
1442 or "/*" and the text from the 'foldmarker' and 'commentstring'
1443 options is removed.
1444 {not available when compiled without the |+folding| feature}
1445
1446 *foreground()*
1447foreground() Move the Vim window to the foreground. Useful when sent from
1448 a client to a Vim server. |remote_send()|
1449 On Win32 systems this might not work, the OS does not always
1450 allow a window to bring itself to the foreground. Use
1451 |remote_foreground()| instead.
1452 {only in the Win32, Athena, Motif and GTK GUI versions and the
1453 Win32 console version}
1454
1455getchar([expr]) *getchar()*
1456 Get a single character from the user. If it is an 8-bit
1457 character, the result is a number. Otherwise a String is
1458 returned with the encoded character. For a special key it's a
1459 sequence of bytes starting with 0x80 (decimal: 128).
1460 If [expr] is omitted, wait until a character is available.
1461 If [expr] is 0, only get a character when one is available.
1462 If [expr] is 1, only check if a character is available, it is
1463 not consumed. If a normal character is
1464 available, it is returned, otherwise a
1465 non-zero value is returned.
1466 If a normal character available, it is returned as a Number.
1467 Use nr2char() to convert it to a String.
1468 The returned value is zero if no character is available.
1469 The returned value is a string of characters for special keys
1470 and when a modifier (shift, control, alt) was used.
1471 There is no prompt, you will somehow have to make clear to the
1472 user that a character has to be typed.
1473 There is no mapping for the character.
1474 Key codes are replaced, thus when the user presses the <Del>
1475 key you get the code for the <Del> key, not the raw character
1476 sequence. Examples: >
1477 getchar() == "\<Del>"
1478 getchar() == "\<S-Left>"
1479< This example redefines "f" to ignore case: >
1480 :nmap f :call FindChar()<CR>
1481 :function FindChar()
1482 : let c = nr2char(getchar())
1483 : while col('.') < col('$') - 1
1484 : normal l
1485 : if getline('.')[col('.') - 1] ==? c
1486 : break
1487 : endif
1488 : endwhile
1489 :endfunction
1490
1491getcharmod() *getcharmod()*
1492 The result is a Number which is the state of the modifiers for
1493 the last obtained character with getchar() or in another way.
1494 These values are added together:
1495 2 shift
1496 4 control
1497 8 alt (meta)
1498 16 mouse double click
1499 32 mouse triple click
1500 64 mouse quadruple click
1501 128 Macintosh only: command
1502 Only the modifiers that have not been included in the
1503 character itself are obtained. Thus Shift-a results in "A"
1504 with no modifier.
1505
1506getbufvar({expr}, {varname}) *getbufvar()*
1507 The result is the value of option or local buffer variable
1508 {varname} in buffer {expr}. Note that the name without "b:"
1509 must be used.
1510 This also works for a global or local window option, but it
1511 doesn't work for a global or local window variable.
1512 For the use of {expr}, see |bufname()| above.
1513 When the buffer or variable doesn't exist an empty string is
1514 returned, there is no error message.
1515 Examples: >
1516 :let bufmodified = getbufvar(1, "&mod")
1517 :echo "todo myvar = " . getbufvar("todo", "myvar")
1518<
1519getcmdline() *getcmdline()*
1520 Return the current command-line. Only works when the command
1521 line is being edited, thus requires use of |c_CTRL-\_e| or
1522 |c_CTRL-R_=|.
1523 Example: >
1524 :cmap <F7> <C-\>eescape(getcmdline(), ' \')<CR>
1525< Also see |getcmdpos()| and |setcmdpos()|.
1526
1527getcmdpos({pos}) *getcmdpos()*
1528 Return the position of the cursor in the command line as a
1529 byte count. The first column is 1.
1530 Only works when editing the command line, thus requires use of
1531 |c_CTRL-\_e| or |c_CTRL-R_=|. Returns 0 otherwise.
1532 Also see |setcmdpos()| and |getcmdline()|.
1533
1534 *getcwd()*
1535getcwd() The result is a String, which is the name of the current
1536 working directory.
1537
1538getfsize({fname}) *getfsize()*
1539 The result is a Number, which is the size in bytes of the
1540 given file {fname}.
1541 If {fname} is a directory, 0 is returned.
1542 If the file {fname} can't be found, -1 is returned.
1543
1544getftime({fname}) *getftime()*
1545 The result is a Number, which is the last modification time of
1546 the given file {fname}. The value is measured as seconds
1547 since 1st Jan 1970, and may be passed to strftime(). See also
1548 |localtime()| and |strftime()|.
1549 If the file {fname} can't be found -1 is returned.
1550
1551 *getline()*
1552getline({lnum}) The result is a String, which is line {lnum} from the current
1553 buffer. Example: >
1554 getline(1)
1555< When {lnum} is a String that doesn't start with a
1556 digit, line() is called to translate the String into a Number.
1557 To get the line under the cursor: >
1558 getline(".")
1559< When {lnum} is smaller than 1 or bigger than the number of
1560 lines in the buffer, an empty string is returned.
1561
1562getreg([{regname}]) *getreg()*
1563 The result is a String, which is the contents of register
1564 {regname}. Example: >
1565 :let cliptext = getreg('*')
1566< getreg('=') returns the last evaluated value of the expression
1567 register. (For use in maps).
1568 If {regname} is not specified, |v:register| is used.
1569
1570getregtype([{regname}]) *getregtype()*
1571 The result is a String, which is type of register {regname}.
1572 The value will be one of:
1573 "v" for |characterwise| text
1574 "V" for |linewise| text
1575 "<CTRL-V>{width}" for |blockwise-visual| text
1576 0 for an empty or unknown register
1577 <CTRL-V> is one character with value 0x16.
1578 If {regname} is not specified, |v:register| is used.
1579
1580 *getwinposx()*
1581getwinposx() The result is a Number, which is the X coordinate in pixels of
1582 the left hand side of the GUI Vim window. The result will be
1583 -1 if the information is not available.
1584
1585 *getwinposy()*
1586getwinposy() The result is a Number, which is the Y coordinate in pixels of
1587 the top of the GUI Vim window. The result will be -1 if the
1588 information is not available.
1589
1590getwinvar({nr}, {varname}) *getwinvar()*
1591 The result is the value of option or local window variable
1592 {varname} in window {nr}.
1593 This also works for a global or local buffer option, but it
1594 doesn't work for a global or local buffer variable.
1595 Note that the name without "w:" must be used.
1596 Examples: >
1597 :let list_is_on = getwinvar(2, '&list')
1598 :echo "myvar = " . getwinvar(1, 'myvar')
1599<
1600 *glob()*
1601glob({expr}) Expand the file wildcards in {expr}. The result is a String.
1602 When there are several matches, they are separated by <NL>
1603 characters.
1604 If the expansion fails, the result is an empty string.
1605 A name for a non-existing file is not included.
1606
1607 For most systems backticks can be used to get files names from
1608 any external command. Example: >
1609 :let tagfiles = glob("`find . -name tags -print`")
1610 :let &tags = substitute(tagfiles, "\n", ",", "g")
1611< The result of the program inside the backticks should be one
1612 item per line. Spaces inside an item are allowed.
1613
1614 See |expand()| for expanding special Vim variables. See
1615 |system()| for getting the raw output of an external command.
1616
1617globpath({path}, {expr}) *globpath()*
1618 Perform glob() on all directories in {path} and concatenate
1619 the results. Example: >
1620 :echo globpath(&rtp, "syntax/c.vim")
1621< {path} is a comma-separated list of directory names. Each
1622 directory name is prepended to {expr} and expanded like with
1623 glob(). A path separator is inserted when needed.
1624 To add a comma inside a directory name escape it with a
1625 backslash. Note that on MS-Windows a directory may have a
1626 trailing backslash, remove it if you put a comma after it.
1627 If the expansion fails for one of the directories, there is no
1628 error message.
1629 The 'wildignore' option applies: Names matching one of the
1630 patterns in 'wildignore' will be skipped.
1631
1632 *has()*
1633has({feature}) The result is a Number, which is 1 if the feature {feature} is
1634 supported, zero otherwise. The {feature} argument is a
1635 string. See |feature-list| below.
1636 Also see |exists()|.
1637
1638hasmapto({what} [, {mode}]) *hasmapto()*
1639 The result is a Number, which is 1 if there is a mapping that
1640 contains {what} in somewhere in the rhs (what it is mapped to)
1641 and this mapping exists in one of the modes indicated by
1642 {mode}.
1643 Both the global mappings and the mappings local to the current
1644 buffer are checked for a match.
1645 If no matching mapping is found 0 is returned.
1646 The following characters are recognized in {mode}:
1647 n Normal mode
1648 v Visual mode
1649 o Operator-pending mode
1650 i Insert mode
1651 l Language-Argument ("r", "f", "t", etc.)
1652 c Command-line mode
1653 When {mode} is omitted, "nvo" is used.
1654
1655 This function is useful to check if a mapping already exists
1656 to a function in a Vim script. Example: >
1657 :if !hasmapto('\ABCdoit')
1658 : map <Leader>d \ABCdoit
1659 :endif
1660< This installs the mapping to "\ABCdoit" only if there isn't
1661 already a mapping to "\ABCdoit".
1662
1663histadd({history}, {item}) *histadd()*
1664 Add the String {item} to the history {history} which can be
1665 one of: *hist-names*
1666 "cmd" or ":" command line history
1667 "search" or "/" search pattern history
1668 "expr" or "=" typed expression history
1669 "input" or "@" input line history
1670 If {item} does already exist in the history, it will be
1671 shifted to become the newest entry.
1672 The result is a Number: 1 if the operation was successful,
1673 otherwise 0 is returned.
1674
1675 Example: >
1676 :call histadd("input", strftime("%Y %b %d"))
1677 :let date=input("Enter date: ")
1678< This function is not available in the |sandbox|.
1679
1680histdel({history} [, {item}]) *histdel()*
1681 Clear {history}, ie. delete all its entries. See |hist-names|
1682 for the possible values of {history}.
1683
1684 If the parameter {item} is given as String, this is seen
1685 as regular expression. All entries matching that expression
1686 will be removed from the history (if there are any).
1687 Upper/lowercase must match, unless "\c" is used |/\c|.
1688 If {item} is a Number, it will be interpreted as index, see
1689 |:history-indexing|. The respective entry will be removed
1690 if it exists.
1691
1692 The result is a Number: 1 for a successful operation,
1693 otherwise 0 is returned.
1694
1695 Examples:
1696 Clear expression register history: >
1697 :call histdel("expr")
1698<
1699 Remove all entries starting with "*" from the search history: >
1700 :call histdel("/", '^\*')
1701<
1702 The following three are equivalent: >
1703 :call histdel("search", histnr("search"))
1704 :call histdel("search", -1)
1705 :call histdel("search", '^'.histget("search", -1).'$')
1706<
1707 To delete the last search pattern and use the last-but-one for
1708 the "n" command and 'hlsearch': >
1709 :call histdel("search", -1)
1710 :let @/ = histget("search", -1)
1711
1712histget({history} [, {index}]) *histget()*
1713 The result is a String, the entry with Number {index} from
1714 {history}. See |hist-names| for the possible values of
1715 {history}, and |:history-indexing| for {index}. If there is
1716 no such entry, an empty String is returned. When {index} is
1717 omitted, the most recent item from the history is used.
1718
1719 Examples:
1720 Redo the second last search from history. >
1721 :execute '/' . histget("search", -2)
1722
1723< Define an Ex command ":H {num}" that supports re-execution of
1724 the {num}th entry from the output of |:history|. >
1725 :command -nargs=1 H execute histget("cmd", 0+<args>)
1726<
1727histnr({history}) *histnr()*
1728 The result is the Number of the current entry in {history}.
1729 See |hist-names| for the possible values of {history}.
1730 If an error occurred, -1 is returned.
1731
1732 Example: >
1733 :let inp_index = histnr("expr")
1734<
1735hlexists({name}) *hlexists()*
1736 The result is a Number, which is non-zero if a highlight group
1737 called {name} exists. This is when the group has been
1738 defined in some way. Not necessarily when highlighting has
1739 been defined for it, it may also have been used for a syntax
1740 item.
1741 *highlight_exists()*
1742 Obsolete name: highlight_exists().
1743
1744 *hlID()*
1745hlID({name}) The result is a Number, which is the ID of the highlight group
1746 with name {name}. When the highlight group doesn't exist,
1747 zero is returned.
1748 This can be used to retrieve information about the highlight
1749 group. For example, to get the background color of the
1750 "Comment" group: >
1751 :echo synIDattr(synIDtrans(hlID("Comment")), "bg")
1752< *highlightID()*
1753 Obsolete name: highlightID().
1754
1755hostname() *hostname()*
1756 The result is a String, which is the name of the machine on
1757 which Vim is currently running. Machine names greater than
1758 256 characters long are truncated.
1759
1760iconv({expr}, {from}, {to}) *iconv()*
1761 The result is a String, which is the text {expr} converted
1762 from encoding {from} to encoding {to}.
1763 When the conversion fails an empty string is returned.
1764 The encoding names are whatever the iconv() library function
1765 can accept, see ":!man 3 iconv".
1766 Most conversions require Vim to be compiled with the |+iconv|
1767 feature. Otherwise only UTF-8 to latin1 conversion and back
1768 can be done.
1769 This can be used to display messages with special characters,
1770 no matter what 'encoding' is set to. Write the message in
1771 UTF-8 and use: >
1772 echo iconv(utf8_str, "utf-8", &enc)
1773< Note that Vim uses UTF-8 for all Unicode encodings, conversion
1774 from/to UCS-2 is automatically changed to use UTF-8. You
1775 cannot use UCS-2 in a string anyway, because of the NUL bytes.
1776 {only available when compiled with the +multi_byte feature}
1777
1778 *indent()*
1779indent({lnum}) The result is a Number, which is indent of line {lnum} in the
1780 current buffer. The indent is counted in spaces, the value
1781 of 'tabstop' is relevant. {lnum} is used just like in
1782 |getline()|.
1783 When {lnum} is invalid -1 is returned.
1784
1785input({prompt} [, {text}]) *input()*
1786 The result is a String, which is whatever the user typed on
1787 the command-line. The parameter is either a prompt string, or
1788 a blank string (for no prompt). A '\n' can be used in the
1789 prompt to start a new line. The highlighting set with
1790 |:echohl| is used for the prompt. The input is entered just
1791 like a command-line, with the same editing commands and
1792 mappings. There is a separate history for lines typed for
1793 input().
1794 If the optional {text} is present, this is used for the
1795 default reply, as if the user typed this.
1796 NOTE: This must not be used in a startup file, for the
1797 versions that only run in GUI mode (e.g., the Win32 GUI).
1798 Note: When input() is called from within a mapping it will
1799 consume remaining characters from that mapping, because a
1800 mapping is handled like the characters were typed.
1801 Use |inputsave()| before input() and |inputrestore()|
1802 after input() to avoid that. Another solution is to avoid
1803 that further characters follow in the mapping, e.g., by using
1804 |:execute| or |:normal|.
1805
1806 Example: >
1807 :if input("Coffee or beer? ") == "beer"
1808 : echo "Cheers!"
1809 :endif
1810< Example with default text: >
1811 :let color = input("Color? ", "white")
1812< Example with a mapping: >
1813 :nmap \x :call GetFoo()<CR>:exe "/" . Foo<CR>
1814 :function GetFoo()
1815 : call inputsave()
1816 : let g:Foo = input("enter search pattern: ")
1817 : call inputrestore()
1818 :endfunction
1819
1820inputdialog({prompt} [, {text} [, {cancelreturn}]]) *inputdialog()*
1821 Like input(), but when the GUI is running and text dialogs are
1822 supported, a dialog window pops up to input the text.
1823 Example: >
1824 :let n = inputdialog("value for shiftwidth", &sw)
1825 :if n != ""
1826 : let &sw = n
1827 :endif
1828< When the dialog is cancelled {cancelreturn} is returned. When
1829 omitted an empty string is returned.
1830 Hitting <Enter> works like pressing the OK button. Hitting
1831 <Esc> works like pressing the Cancel button.
1832
1833inputrestore() *inputrestore()*
1834 Restore typeahead that was saved with a previous inputsave().
1835 Should be called the same number of times inputsave() is
1836 called. Calling it more often is harmless though.
1837 Returns 1 when there is nothing to restore, 0 otherwise.
1838
1839inputsave() *inputsave()*
1840 Preserve typeahead (also from mappings) and clear it, so that
1841 a following prompt gets input from the user. Should be
1842 followed by a matching inputrestore() after the prompt. Can
1843 be used several times, in which case there must be just as
1844 many inputrestore() calls.
1845 Returns 1 when out of memory, 0 otherwise.
1846
1847inputsecret({prompt} [, {text}]) *inputsecret()*
1848 This function acts much like the |input()| function with but
1849 two exceptions:
1850 a) the user's response will be displayed as a sequence of
1851 asterisks ("*") thereby keeping the entry secret, and
1852 b) the user's response will not be recorded on the input
1853 |history| stack.
1854 The result is a String, which is whatever the user actually
1855 typed on the command-line in response to the issued prompt.
1856
1857isdirectory({directory}) *isdirectory()*
1858 The result is a Number, which is non-zero when a directory
1859 with the name {directory} exists. If {directory} doesn't
1860 exist, or isn't a directory, the result is FALSE. {directory}
1861 is any expression, which is used as a String.
1862
1863 *libcall()* *E364* *E368*
1864libcall({libname}, {funcname}, {argument})
1865 Call function {funcname} in the run-time library {libname}
1866 with single argument {argument}.
1867 This is useful to call functions in a library that you
1868 especially made to be used with Vim. Since only one argument
1869 is possible, calling standard library functions is rather
1870 limited.
1871 The result is the String returned by the function. If the
1872 function returns NULL, this will appear as an empty string ""
1873 to Vim.
1874 If the function returns a number, use libcallnr()!
1875 If {argument} is a number, it is passed to the function as an
1876 int; if {argument} is a string, it is passed as a
1877 null-terminated string.
1878 This function will fail in |restricted-mode|.
1879
1880 libcall() allows you to write your own 'plug-in' extensions to
1881 Vim without having to recompile the program. It is NOT a
1882 means to call system functions! If you try to do so Vim will
1883 very probably crash.
1884
1885 For Win32, the functions you write must be placed in a DLL
1886 and use the normal C calling convention (NOT Pascal which is
1887 used in Windows System DLLs). The function must take exactly
1888 one parameter, either a character pointer or a long integer,
1889 and must return a character pointer or NULL. The character
1890 pointer returned must point to memory that will remain valid
1891 after the function has returned (e.g. in static data in the
1892 DLL). If it points to allocated memory, that memory will
1893 leak away. Using a static buffer in the function should work,
1894 it's then freed when the DLL is unloaded.
1895
1896 WARNING: If the function returns a non-valid pointer, Vim may
1897 crash! This also happens if the function returns a number,
1898 because Vim thinks it's a pointer.
1899 For Win32 systems, {libname} should be the filename of the DLL
1900 without the ".DLL" suffix. A full path is only required if
1901 the DLL is not in the usual places.
1902 For Unix: When compiling your own plugins, remember that the
1903 object code must be compiled as position-independent ('PIC').
1904 {only in Win32 on some Unix versions, when the |+libcall|
1905 feature is present}
1906 Examples: >
1907 :echo libcall("libc.so", "getenv", "HOME")
1908 :echo libcallnr("/usr/lib/libc.so", "getpid", "")
1909<
1910 *libcallnr()*
1911libcallnr({libname}, {funcname}, {argument})
1912 Just like libcall(), but used for a function that returns an
1913 int instead of a string.
1914 {only in Win32 on some Unix versions, when the |+libcall|
1915 feature is present}
1916 Example (not very useful...): >
1917 :call libcallnr("libc.so", "printf", "Hello World!\n")
1918 :call libcallnr("libc.so", "sleep", 10)
1919<
1920 *line()*
1921line({expr}) The result is a Number, which is the line number of the file
1922 position given with {expr}. The accepted positions are:
1923 . the cursor position
1924 $ the last line in the current buffer
1925 'x position of mark x (if the mark is not set, 0 is
1926 returned)
1927 Note that only marks in the current file can be used.
1928 Examples: >
1929 line(".") line number of the cursor
1930 line("'t") line number of mark t
1931 line("'" . marker) line number of mark marker
1932< *last-position-jump*
1933 This autocommand jumps to the last known position in a file
1934 just after opening it, if the '" mark is set: >
1935 :au BufReadPost * if line("'\"") > 0 && line("'\"") <= line("$") | exe "normal g'\"" | endif
Bram Moolenaar69a7cb42004-06-20 12:51:53 +00001936
Bram Moolenaar071d4272004-06-13 20:20:40 +00001937line2byte({lnum}) *line2byte()*
1938 Return the byte count from the start of the buffer for line
1939 {lnum}. This includes the end-of-line character, depending on
1940 the 'fileformat' option for the current buffer. The first
1941 line returns 1.
1942 This can also be used to get the byte count for the line just
1943 below the last line: >
1944 line2byte(line("$") + 1)
1945< This is the file size plus one.
1946 When {lnum} is invalid, or the |+byte_offset| feature has been
1947 disabled at compile time, -1 is returned.
1948 Also see |byte2line()|, |go| and |:goto|.
1949
1950lispindent({lnum}) *lispindent()*
1951 Get the amount of indent for line {lnum} according the lisp
1952 indenting rules, as with 'lisp'.
1953 The indent is counted in spaces, the value of 'tabstop' is
1954 relevant. {lnum} is used just like in |getline()|.
1955 When {lnum} is invalid or Vim was not compiled the
1956 |+lispindent| feature, -1 is returned.
1957
1958localtime() *localtime()*
1959 Return the current time, measured as seconds since 1st Jan
1960 1970. See also |strftime()| and |getftime()|.
1961
1962maparg({name}[, {mode}]) *maparg()*
1963 Return the rhs of mapping {name} in mode {mode}. When there
1964 is no mapping for {name}, an empty String is returned.
1965 These characters can be used for {mode}:
1966 "n" Normal
1967 "v" Visual
1968 "o" Operator-pending
1969 "i" Insert
1970 "c" Cmd-line
1971 "l" langmap |language-mapping|
1972 "" Normal, Visual and Operator-pending
1973 When {mode} is omitted, the modes from "" are used.
1974 The {name} can have special key names, like in the ":map"
1975 command. The returned String has special characters
1976 translated like in the output of the ":map" command listing.
1977 The mappings local to the current buffer are checked first,
1978 then the global mappings.
1979
1980mapcheck({name}[, {mode}]) *mapcheck()*
1981 Check if there is a mapping that matches with {name} in mode
1982 {mode}. See |maparg()| for {mode} and special names in
1983 {name}.
1984 A match happens with a mapping that starts with {name} and
1985 with a mapping which is equal to the start of {name}.
1986
1987 matches mapping "a" "ab" "abc" ~
1988 mapcheck("a") yes yes yes
1989 mapcheck("abc") yes yes yes
1990 mapcheck("ax") yes no no
1991 mapcheck("b") no no no
1992
1993 The difference with maparg() is that mapcheck() finds a
1994 mapping that matches with {name}, while maparg() only finds a
1995 mapping for {name} exactly.
1996 When there is no mapping that starts with {name}, an empty
1997 String is returned. If there is one, the rhs of that mapping
1998 is returned. If there are several mappings that start with
1999 {name}, the rhs of one of them is returned.
2000 The mappings local to the current buffer are checked first,
2001 then the global mappings.
2002 This function can be used to check if a mapping can be added
2003 without being ambiguous. Example: >
2004 :if mapcheck("_vv") == ""
2005 : map _vv :set guifont=7x13<CR>
2006 :endif
2007< This avoids adding the "_vv" mapping when there already is a
2008 mapping for "_v" or for "_vvv".
2009
2010match({expr}, {pat}[, {start}]) *match()*
2011 The result is a Number, which gives the index (byte offset) in
2012 {expr} where {pat} matches. A match at the first character
2013 returns zero. If there is no match -1 is returned. Example: >
2014 :echo match("testing", "ing")
2015< results in "4".
2016 See |string-match| for how {pat} is used.
2017 If {start} is given, the search starts from index {start}.
2018 The result, however, is still the index counted from the
2019 first character. Example: >
2020 :echo match("testing", "ing", 2)
2021< result is again "4". >
2022 :echo match("testing", "ing", 4)
2023< result is again "4". >
2024 :echo match("testing", "t", 2)
2025< result is "3".
2026 If {start} < 0, it will be set to 0.
2027 If {start} > strlen({expr}) -1 is returned.
2028 See |pattern| for the patterns that are accepted.
2029 The 'ignorecase' option is used to set the ignore-caseness of
2030 the pattern. 'smartcase' is NOT used. The matching is always
2031 done like 'magic' is set and 'cpoptions' is empty.
2032
2033matchend({expr}, {pat}[, {start}]) *matchend()*
2034 Same as match(), but return the index of first character after
2035 the match. Example: >
2036 :echo matchend("testing", "ing")
2037< results in "7".
2038 The {start}, if given, has the same meaning as for match(). >
2039 :echo matchend("testing", "ing", 2)
2040< results in "7". >
2041 :echo matchend("testing", "ing", 5)
2042< result is "-1".
2043
2044matchstr({expr}, {pat}[, {start}]) *matchstr()*
2045 Same as match(), but return the matched string. Example: >
2046 :echo matchstr("testing", "ing")
2047< results in "ing".
2048 When there is no match "" is returned.
2049 The {start}, if given, has the same meaning as for match(). >
2050 :echo matchstr("testing", "ing", 2)
2051< results in "ing". >
2052 :echo matchstr("testing", "ing", 5)
2053< result is "".
2054
2055 *mode()*
2056mode() Return a string that indicates the current mode:
2057 n Normal
2058 v Visual by character
2059 V Visual by line
2060 CTRL-V Visual blockwise
2061 s Select by character
2062 S Select by line
2063 CTRL-S Select blockwise
2064 i Insert
2065 R Replace
2066 c Command-line
2067 r Hit-enter prompt
2068 This is useful in the 'statusline' option. In most other
2069 places it always returns "c" or "n".
2070
2071nextnonblank({lnum}) *nextnonblank()*
2072 Return the line number of the first line at or below {lnum}
2073 that is not blank. Example: >
2074 if getline(nextnonblank(1)) =~ "Java"
2075< When {lnum} is invalid or there is no non-blank line at or
2076 below it, zero is returned.
2077 See also |prevnonblank()|.
2078
2079nr2char({expr}) *nr2char()*
2080 Return a string with a single character, which has the number
2081 value {expr}. Examples: >
2082 nr2char(64) returns "@"
2083 nr2char(32) returns " "
2084< The current 'encoding' is used. Example for "utf-8": >
2085 nr2char(300) returns I with bow character
2086< Note that a NUL character in the file is specified with
2087 nr2char(10), because NULs are represented with newline
2088 characters. nr2char(0) is a real NUL and terminates the
2089 string, thus isn't very useful.
2090
2091prevnonblank({lnum}) *prevnonblank()*
2092 Return the line number of the first line at or above {lnum}
2093 that is not blank. Example: >
2094 let ind = indent(prevnonblank(v:lnum - 1))
2095< When {lnum} is invalid or there is no non-blank line at or
2096 above it, zero is returned.
2097 Also see |nextnonblank()|.
2098
2099 *remote_expr()* *E449*
2100remote_expr({server}, {string} [, {idvar}])
2101 Send the {string} to {server}. The string is sent as an
2102 expression and the result is returned after evaluation.
2103 If {idvar} is present, it is taken as the name of a
2104 variable and a {serverid} for later use with
2105 remote_read() is stored there.
2106 See also |clientserver| |RemoteReply|.
2107 This function is not available in the |sandbox|.
2108 {only available when compiled with the |+clientserver| feature}
2109 Note: Any errors will cause a local error message to be issued
2110 and the result will be the empty string.
2111 Examples: >
2112 :echo remote_expr("gvim", "2+2")
2113 :echo remote_expr("gvim1", "b:current_syntax")
2114<
2115
2116remote_foreground({server}) *remote_foreground()*
2117 Move the Vim server with the name {server} to the foreground.
2118 This works like: >
2119 remote_expr({server}, "foreground()")
2120< Except that on Win32 systems the client does the work, to work
2121 around the problem that the OS doesn't always allow the server
2122 to bring itself to the foreground.
2123 This function is not available in the |sandbox|.
2124 {only in the Win32, Athena, Motif and GTK GUI versions and the
2125 Win32 console version}
2126
2127
2128remote_peek({serverid} [, {retvar}]) *remote_peek()*
2129 Returns a positive number if there are available strings
2130 from {serverid}. Copies any reply string into the variable
2131 {retvar} if specified. {retvar} must be a string with the
2132 name of a variable.
2133 Returns zero if none are available.
2134 Returns -1 if something is wrong.
2135 See also |clientserver|.
2136 This function is not available in the |sandbox|.
2137 {only available when compiled with the |+clientserver| feature}
2138 Examples: >
2139 :let repl = ""
2140 :echo "PEEK: ".remote_peek(id, "repl").": ".repl
2141
2142remote_read({serverid}) *remote_read()*
2143 Return the oldest available reply from {serverid} and consume
2144 it. It blocks until a reply is available.
2145 See also |clientserver|.
2146 This function is not available in the |sandbox|.
2147 {only available when compiled with the |+clientserver| feature}
2148 Example: >
2149 :echo remote_read(id)
2150<
2151 *remote_send()* *E241*
2152remote_send({server}, {string} [, {idvar}])
2153 Send the {string} to {server}. The string is sent as
2154 input keys and the function returns immediately.
2155 If {idvar} is present, it is taken as the name of a
2156 variable and a {serverid} for later use with
2157 remote_read() is stored there.
2158 See also |clientserver| |RemoteReply|.
2159 This function is not available in the |sandbox|.
2160 {only available when compiled with the |+clientserver| feature}
2161 Note: Any errors will be reported in the server and may mess
2162 up the display.
2163 Examples: >
2164 :echo remote_send("gvim", ":DropAndReply ".file, "serverid").
2165 \ remote_read(serverid)
2166
2167 :autocmd NONE RemoteReply *
2168 \ echo remote_read(expand("<amatch>"))
2169 :echo remote_send("gvim", ":sleep 10 | echo ".
2170 \ 'server2client(expand("<client>"), "HELLO")<CR>')
2171
2172
2173rename({from}, {to}) *rename()*
2174 Rename the file by the name {from} to the name {to}. This
2175 should also work to move files across file systems. The
2176 result is a Number, which is 0 if the file was renamed
2177 successfully, and non-zero when the renaming failed.
2178 This function is not available in the |sandbox|.
2179
2180resolve({filename}) *resolve()* *E655*
2181 On MS-Windows, when {filename} is a shortcut (a .lnk file),
2182 returns the path the shortcut points to in a simplified form.
2183 On Unix, repeat resolving symbolic links in all path
2184 components of {filename} and return the simplified result.
2185 To cope with link cycles, resolving of symbolic links is
2186 stopped after 100 iterations.
2187 On other systems, return the simplified {filename}.
2188 The simplification step is done as by |simplify()|.
2189 resolve() keeps a leading path component specifying the
2190 current directory (provided the result is still a relative
2191 path name) and also keeps a trailing path separator.
2192
2193search({pattern} [, {flags}]) *search()*
2194 Search for regexp pattern {pattern}. The search starts at the
2195 cursor position.
2196 {flags} is a String, which can contain these character flags:
2197 'b' search backward instead of forward
2198 'w' wrap around the end of the file
2199 'W' don't wrap around the end of the file
2200 If neither 'w' or 'W' is given, the 'wrapscan' option applies.
2201
2202 When a match has been found its line number is returned, and
2203 the cursor will be positioned at the match. If there is no
2204 match a 0 is returned and the cursor doesn't move. No error
2205 message is given.
2206
2207 Example (goes over all files in the argument list): >
2208 :let n = 1
2209 :while n <= argc() " loop over all files in arglist
2210 : exe "argument " . n
2211 : " start at the last char in the file and wrap for the
2212 : " first search to find match at start of file
2213 : normal G$
2214 : let flags = "w"
2215 : while search("foo", flags) > 0
2216 : s/foo/bar/g
2217 : let flags = "W"
2218 : endwhile
2219 : update " write the file if modified
2220 : let n = n + 1
2221 :endwhile
2222<
2223 *searchpair()*
2224searchpair({start}, {middle}, {end} [, {flags} [, {skip}]])
2225 Search for the match of a nested start-end pair. This can be
2226 used to find the "endif" that matches an "if", while other
2227 if/endif pairs in between are ignored.
2228 The search starts at the cursor. If a match is found, the
2229 cursor is positioned at it and the line number is returned.
2230 If no match is found 0 or -1 is returned and the cursor
2231 doesn't move. No error message is given.
2232
2233 {start}, {middle} and {end} are patterns, see |pattern|. They
2234 must not contain \( \) pairs. Use of \%( \) is allowed. When
2235 {middle} is not empty, it is found when searching from either
2236 direction, but only when not in a nested start-end pair. A
2237 typical use is: >
2238 searchpair('\<if\>', '\<else\>', '\<endif\>')
2239< By leaving {middle} empty the "else" is skipped.
2240
2241 {flags} are used like with |search()|. Additionally:
2242 'n' do Not move the cursor
2243 'r' Repeat until no more matches found; will find the
2244 outer pair
2245 'm' return number of Matches instead of line number with
2246 the match; will only be > 1 when 'r' is used.
2247
2248 When a match for {start}, {middle} or {end} is found, the
2249 {skip} expression is evaluated with the cursor positioned on
2250 the start of the match. It should return non-zero if this
2251 match is to be skipped. E.g., because it is inside a comment
2252 or a string.
2253 When {skip} is omitted or empty, every match is accepted.
2254 When evaluating {skip} causes an error the search is aborted
2255 and -1 returned.
2256
2257 The value of 'ignorecase' is used. 'magic' is ignored, the
2258 patterns are used like it's on.
2259
2260 The search starts exactly at the cursor. A match with
2261 {start}, {middle} or {end} at the next character, in the
2262 direction of searching, is the first one found. Example: >
2263 if 1
2264 if 2
2265 endif 2
2266 endif 1
2267< When starting at the "if 2", with the cursor on the "i", and
2268 searching forwards, the "endif 2" is found. When starting on
2269 the character just before the "if 2", the "endif 1" will be
2270 found. That's because the "if 2" will be found first, and
2271 then this is considered to be a nested if/endif from "if 2" to
2272 "endif 2".
2273 When searching backwards and {end} is more than one character,
2274 it may be useful to put "\zs" at the end of the pattern, so
2275 that when the cursor is inside a match with the end it finds
2276 the matching start.
2277
2278 Example, to find the "endif" command in a Vim script: >
2279
2280 :echo searchpair('\<if\>', '\<el\%[seif]\>', '\<en\%[dif]\>', 'W',
2281 \ 'getline(".") =~ "^\\s*\""')
2282
2283< The cursor must be at or after the "if" for which a match is
2284 to be found. Note that single-quote strings are used to avoid
2285 having to double the backslashes. The skip expression only
2286 catches comments at the start of a line, not after a command.
2287 Also, a word "en" or "if" halfway a line is considered a
2288 match.
2289 Another example, to search for the matching "{" of a "}": >
2290
2291 :echo searchpair('{', '', '}', 'bW')
2292
2293< This works when the cursor is at or before the "}" for which a
2294 match is to be found. To reject matches that syntax
2295 highlighting recognized as strings: >
2296
2297 :echo searchpair('{', '', '}', 'bW',
2298 \ 'synIDattr(synID(line("."), col("."), 0), "name") =~? "string"')
2299<
2300server2client( {clientid}, {string}) *server2client()*
2301 Send a reply string to {clientid}. The most recent {clientid}
2302 that sent a string can be retrieved with expand("<client>").
2303 {only available when compiled with the |+clientserver| feature}
2304 Note:
2305 This id has to be stored before the next command can be
2306 received. Ie. before returning from the received command and
2307 before calling any commands that waits for input.
2308 See also |clientserver|.
2309 Example: >
2310 :echo server2client(expand("<client>"), "HELLO")
2311<
2312serverlist() *serverlist()*
2313 Return a list of available server names, one per line.
2314 When there are no servers or the information is not available
2315 an empty string is returned. See also |clientserver|.
2316 {only available when compiled with the |+clientserver| feature}
2317 Example: >
2318 :echo serverlist()
2319<
2320setbufvar({expr}, {varname}, {val}) *setbufvar()*
2321 Set option or local variable {varname} in buffer {expr} to
2322 {val}.
2323 This also works for a global or local window option, but it
2324 doesn't work for a global or local window variable.
2325 For a local window option the global value is unchanged.
2326 For the use of {expr}, see |bufname()| above.
2327 Note that the variable name without "b:" must be used.
2328 Examples: >
2329 :call setbufvar(1, "&mod", 1)
2330 :call setbufvar("todo", "myvar", "foobar")
2331< This function is not available in the |sandbox|.
2332
2333setcmdpos({pos}) *setcmdpos()*
2334 Set the cursor position in the command line to byte position
2335 {pos}. The first position is 1.
2336 Use |getcmdpos()| to obtain the current position.
2337 Only works while editing the command line, thus you must use
2338 |c_CTRL-\_e| or |c_CTRL-R_=|. The position is set after the
2339 command line is set to the expression.
2340 When the number is too big the cursor is put at the end of the
2341 line. A number smaller than one has undefined results.
2342 Returns 0 when successful, 1 when not editing the command
2343 line.
2344
2345setline({lnum}, {line}) *setline()*
2346 Set line {lnum} of the current buffer to {line}. If this
2347 succeeds, 0 is returned. If this fails (most likely because
2348 {lnum} is invalid) 1 is returned. Example: >
2349 :call setline(5, strftime("%c"))
2350< Note: The '[ and '] marks are not set.
2351
2352 *setreg()*
2353setreg({regname}, {value} [,{options}])
2354 Set the register {regname} to {value}.
2355 If {options} contains "a" or {regname} is upper case,
2356 then the value is appended.
2357 {options} can also contains a register type specification:
2358 "c" or "v" |characterwise| mode
2359 "l" or "V" |linewise| mode
2360 "b" or "<CTRL-V>" |blockwise-visual| mode
2361 If a number immediately follows "b" or "<CTRL-V>" then this is
2362 used as the width of the selection - if it is not specified
2363 then the width of the block is set to the number of characters
2364 in the longest line (counting a <TAB> as 1 character).
2365
2366 If {options} contains no register settings, then the default
2367 is to use character mode unless {value} ends in a <NL>.
2368 Setting the '=' register is not possible.
2369 Returns zero for success, non-zero for failure.
2370
2371 Examples: >
2372 :call setreg(v:register, @*)
2373 :call setreg('*', @%, 'ac')
2374 :call setreg('a', "1\n2\n3", 'b5')
2375
2376< This example shows using the functions to save and restore a
2377 register. >
2378 :let var_a = getreg('a')
2379 :let var_amode = getregtype('a')
2380 ....
2381 :call setreg('a', var_a, var_amode)
2382
2383< You can also change the type of a register by appending
2384 nothing: >
2385 :call setreg('a', '', 'al')
2386
2387setwinvar({nr}, {varname}, {val}) *setwinvar()*
2388 Set option or local variable {varname} in window {nr} to
2389 {val}.
2390 This also works for a global or local buffer option, but it
2391 doesn't work for a global or local buffer variable.
2392 For a local buffer option the global value is unchanged.
2393 Note that the variable name without "w:" must be used.
2394 Examples: >
2395 :call setwinvar(1, "&list", 0)
2396 :call setwinvar(2, "myvar", "foobar")
2397< This function is not available in the |sandbox|.
2398
2399simplify({filename}) *simplify()*
2400 Simplify the file name as much as possible without changing
2401 the meaning. Shortcuts (on MS-Windows) or symbolic links (on
2402 Unix) are not resolved. If the first path component in
2403 {filename} designates the current directory, this will be
2404 valid for the result as well. A trailing path separator is
2405 not removed either.
2406 Example: >
2407 simplify("./dir/.././/file/") == "./file/"
2408< Note: The combination "dir/.." is only removed if "dir" is
2409 a searchable directory or does not exist. On Unix, it is also
2410 removed when "dir" is a symbolic link within the same
2411 directory. In order to resolve all the involved symbolic
2412 links before simplifying the path name, use |resolve()|.
2413
2414strftime({format} [, {time}]) *strftime()*
2415 The result is a String, which is a formatted date and time, as
2416 specified by the {format} string. The given {time} is used,
2417 or the current time if no time is given. The accepted
2418 {format} depends on your system, thus this is not portable!
2419 See the manual page of the C function strftime() for the
2420 format. The maximum length of the result is 80 characters.
2421 See also |localtime()| and |getftime()|.
2422 The language can be changed with the |:language| command.
2423 Examples: >
2424 :echo strftime("%c") Sun Apr 27 11:49:23 1997
2425 :echo strftime("%Y %b %d %X") 1997 Apr 27 11:53:25
2426 :echo strftime("%y%m%d %T") 970427 11:53:55
2427 :echo strftime("%H:%M") 11:55
2428 :echo strftime("%c", getftime("file.c"))
2429 Show mod time of file.c.
2430<
2431stridx({haystack}, {needle}) *stridx()*
2432 The result is a Number, which gives the index in {haystack} of
2433 the first occurrence of the String {needle} in the String
2434 {haystack}. The search is done case-sensitive. For advanced
2435 searches use |match()|.
2436 If the {needle} does not occur in {haystack} it returns -1.
2437 See also |strridx()|. Examples: >
2438 :echo stridx("An Example", "Example") 3
2439 :echo stridx("Starting point", "Start") 0
2440 :echo stridx("Starting point", "start") -1
2441<
2442 *strlen()*
2443strlen({expr}) The result is a Number, which is the length of the String
2444 {expr} in bytes. If you want to count the number of
2445 multi-byte characters use something like this: >
2446
2447 :let len = strlen(substitute(str, ".", "x", "g"))
2448
2449< Composing characters are not counted.
2450
2451strpart({src}, {start}[, {len}]) *strpart()*
2452 The result is a String, which is part of {src}, starting from
2453 byte {start}, with the length {len}.
2454 When non-existing bytes are included, this doesn't result in
2455 an error, the bytes are simply omitted.
2456 If {len} is missing, the copy continues from {start} till the
2457 end of the {src}. >
2458 strpart("abcdefg", 3, 2) == "de"
2459 strpart("abcdefg", -2, 4) == "ab"
2460 strpart("abcdefg", 5, 4) == "fg"
2461 strpart("abcdefg", 3) == "defg"
2462< Note: To get the first character, {start} must be 0. For
2463 example, to get three bytes under and after the cursor: >
2464 strpart(getline(line(".")), col(".") - 1, 3)
2465<
2466strridx({haystack}, {needle}) *strridx()*
2467 The result is a Number, which gives the index in {haystack} of
2468 the last occurrence of the String {needle} in the String
2469 {haystack}. The search is done case-sensitive. For advanced
2470 searches use |match()|.
2471 If the {needle} does not occur in {haystack} it returns -1.
2472 See also |stridx()|. Examples: >
2473 :echo strridx("an angry armadillo", "an") 3
2474<
2475strtrans({expr}) *strtrans()*
2476 The result is a String, which is {expr} with all unprintable
2477 characters translated into printable characters |'isprint'|.
2478 Like they are shown in a window. Example: >
2479 echo strtrans(@a)
2480< This displays a newline in register a as "^@" instead of
2481 starting a new line.
2482
2483submatch({nr}) *submatch()*
2484 Only for an expression in a |:substitute| command. Returns
2485 the {nr}'th submatch of the matched text. When {nr} is 0
2486 the whole matched text is returned.
2487 Example: >
2488 :s/\d\+/\=submatch(0) + 1/
2489< This finds the first number in the line and adds one to it.
2490 A line break is included as a newline character.
2491
2492substitute({expr}, {pat}, {sub}, {flags}) *substitute()*
2493 The result is a String, which is a copy of {expr}, in which
2494 the first match of {pat} is replaced with {sub}. This works
2495 like the ":substitute" command (without any flags). But the
2496 matching with {pat} is always done like the 'magic' option is
2497 set and 'cpoptions' is empty (to make scripts portable).
2498 See |string-match| for how {pat} is used.
2499 And a "~" in {sub} is not replaced with the previous {sub}.
2500 Note that some codes in {sub} have a special meaning
2501 |sub-replace-special|. For example, to replace something with
2502 "\n" (two characters), use "\\\\n" or '\\n'.
2503 When {pat} does not match in {expr}, {expr} is returned
2504 unmodified.
2505 When {flags} is "g", all matches of {pat} in {expr} are
2506 replaced. Otherwise {flags} should be "".
2507 Example: >
2508 :let &path = substitute(&path, ",\\=[^,]*$", "", "")
2509< This removes the last component of the 'path' option. >
2510 :echo substitute("testing", ".*", "\\U\\0", "")
2511< results in "TESTING".
2512
2513synID({line}, {col}, {trans}) *synID()*
2514 The result is a Number, which is the syntax ID at the position
2515 {line} and {col} in the current window.
2516 The syntax ID can be used with |synIDattr()| and
2517 |synIDtrans()| to obtain syntax information about text.
2518 {col} is 1 for the leftmost column, {line} is 1 for the first
2519 line.
2520 When {trans} is non-zero, transparent items are reduced to the
2521 item that they reveal. This is useful when wanting to know
2522 the effective color. When {trans} is zero, the transparent
2523 item is returned. This is useful when wanting to know which
2524 syntax item is effective (e.g. inside parens).
2525 Warning: This function can be very slow. Best speed is
2526 obtained by going through the file in forward direction.
2527
2528 Example (echoes the name of the syntax item under the cursor): >
2529 :echo synIDattr(synID(line("."), col("."), 1), "name")
2530<
2531synIDattr({synID}, {what} [, {mode}]) *synIDattr()*
2532 The result is a String, which is the {what} attribute of
2533 syntax ID {synID}. This can be used to obtain information
2534 about a syntax item.
2535 {mode} can be "gui", "cterm" or "term", to get the attributes
2536 for that mode. When {mode} is omitted, or an invalid value is
2537 used, the attributes for the currently active highlighting are
2538 used (GUI, cterm or term).
2539 Use synIDtrans() to follow linked highlight groups.
2540 {what} result
2541 "name" the name of the syntax item
2542 "fg" foreground color (GUI: color name used to set
2543 the color, cterm: color number as a string,
2544 term: empty string)
2545 "bg" background color (like "fg")
2546 "fg#" like "fg", but for the GUI and the GUI is
2547 running the name in "#RRGGBB" form
2548 "bg#" like "fg#" for "bg"
2549 "bold" "1" if bold
2550 "italic" "1" if italic
2551 "reverse" "1" if reverse
2552 "inverse" "1" if inverse (= reverse)
2553 "underline" "1" if underlined
2554
2555 Example (echoes the color of the syntax item under the
2556 cursor): >
2557 :echo synIDattr(synIDtrans(synID(line("."), col("."), 1)), "fg")
2558<
2559synIDtrans({synID}) *synIDtrans()*
2560 The result is a Number, which is the translated syntax ID of
2561 {synID}. This is the syntax group ID of what is being used to
2562 highlight the character. Highlight links given with
2563 ":highlight link" are followed.
2564
2565 *system()*
2566system({expr}) Get the output of the shell command {expr}. Note: newlines
2567 in {expr} may cause the command to fail. The characters in
2568 'shellquote' and 'shellxquote' may also cause trouble.
2569 This is not to be used for interactive commands.
2570 The result is a String. Example: >
2571
2572 :let files = system("ls")
2573
2574< To make the result more system-independent, the shell output
2575 is filtered to replace <CR> with <NL> for Macintosh, and
2576 <CR><NL> with <NL> for DOS-like systems.
2577 The command executed is constructed using several options:
2578 'shell' 'shellcmdflag' 'shellxquote' {expr} 'shellredir' {tmp} 'shellxquote'
2579 ({tmp} is an automatically generated file name).
2580 For Unix and OS/2 braces are put around {expr} to allow for
2581 concatenated commands.
2582
2583 The resulting error code can be found in |v:shell_error|.
2584 This function will fail in |restricted-mode|.
2585 Unlike ":!cmd" there is no automatic check for changed files.
2586 Use |:checktime| to force a check.
2587
2588tempname() *tempname()* *temp-file-name*
2589 The result is a String, which is the name of a file that
2590 doesn't exist. It can be used for a temporary file. The name
2591 is different for at least 26 consecutive calls. Example: >
2592 :let tmpfile = tempname()
2593 :exe "redir > " . tmpfile
2594< For Unix, the file will be in a private directory (only
2595 accessible by the current user) to avoid security problems
2596 (e.g., a symlink attack or other people reading your file).
2597 When Vim exits the directory and all files in it are deleted.
2598 For MS-Windows forward slashes are used when the 'shellslash'
2599 option is set or when 'shellcmdflag' starts with '-'.
2600
2601tolower({expr}) *tolower()*
2602 The result is a copy of the String given, with all uppercase
2603 characters turned into lowercase (just like applying |gu| to
2604 the string).
2605
2606toupper({expr}) *toupper()*
2607 The result is a copy of the String given, with all lowercase
2608 characters turned into uppercase (just like applying |gU| to
2609 the string).
2610
2611type({expr}) *type()*
2612 The result is a Number:
2613 0 if {expr} has the type Number
2614 1 if {expr} has the type String
2615
2616virtcol({expr}) *virtcol()*
2617 The result is a Number, which is the screen column of the file
2618 position given with {expr}. That is, the last screen position
2619 occupied by the character at that position, when the screen
2620 would be of unlimited width. When there is a <Tab> at the
2621 position, the returned Number will be the column at the end of
2622 the <Tab>. For example, for a <Tab> in column 1, with 'ts'
2623 set to 8, it returns 8.
2624 For the byte position use |col()|.
2625 When Virtual editing is active in the current mode, a position
2626 beyond the end of the line can be returned. |'virtualedit'|
2627 The accepted positions are:
2628 . the cursor position
2629 $ the end of the cursor line (the result is the
2630 number of displayed characters in the cursor line
2631 plus one)
2632 'x position of mark x (if the mark is not set, 0 is
2633 returned)
2634 Note that only marks in the current file can be used.
2635 Examples: >
2636 virtcol(".") with text "foo^Lbar", with cursor on the "^L", returns 5
2637 virtcol("$") with text "foo^Lbar", returns 9
2638 virtcol("'t") with text " there", with 't at 'h', returns 6
2639< The first column is 1. 0 is returned for an error.
2640
2641visualmode([expr]) *visualmode()*
2642 The result is a String, which describes the last Visual mode
2643 used. Initially it returns an empty string, but once Visual
2644 mode has been used, it returns "v", "V", or "<CTRL-V>" (a
2645 single CTRL-V character) for character-wise, line-wise, or
2646 block-wise Visual mode respectively.
2647 Example: >
2648 :exe "normal " . visualmode()
2649< This enters the same Visual mode as before. It is also useful
2650 in scripts if you wish to act differently depending on the
2651 Visual mode that was used.
2652
2653 If an expression is supplied that results in a non-zero number
2654 or a non-empty string, then the Visual mode will be cleared
2655 and the old value is returned. Note that " " and "0" are also
2656 non-empty strings, thus cause the mode to be cleared.
2657
2658 *winbufnr()*
2659winbufnr({nr}) The result is a Number, which is the number of the buffer
2660 associated with window {nr}. When {nr} is zero, the number of
2661 the buffer in the current window is returned. When window
2662 {nr} doesn't exist, -1 is returned.
2663 Example: >
2664 :echo "The file in the current window is " . bufname(winbufnr(0))
2665<
2666 *wincol()*
2667wincol() The result is a Number, which is the virtual column of the
2668 cursor in the window. This is counting screen cells from the
2669 left side of the window. The leftmost column is one.
2670
2671winheight({nr}) *winheight()*
2672 The result is a Number, which is the height of window {nr}.
2673 When {nr} is zero, the height of the current window is
2674 returned. When window {nr} doesn't exist, -1 is returned.
2675 An existing window always has a height of zero or more.
2676 Examples: >
2677 :echo "The current window has " . winheight(0) . " lines."
2678<
2679 *winline()*
2680winline() The result is a Number, which is the screen line of the cursor
2681 in the window. This is counting screen lines from the top of
2682 the window. The first line is one.
2683
2684 *winnr()*
2685winnr() The result is a Number, which is the number of the current
2686 window. The top window has number 1. The number can be used
2687 with |CTRL-W_w| and ":wincmd w" |:wincmd|.
2688
2689 *winrestcmd()*
2690winrestcmd() Returns a sequence of |:resize| commands that should restore
2691 the current window sizes. Only works properly when no windows
2692 are opened or closed and the current window is unchanged.
2693 Example: >
2694 :let cmd = winrestcmd()
2695 :call MessWithWindowSizes()
2696 :exe cmd
2697
2698winwidth({nr}) *winwidth()*
2699 The result is a Number, which is the width of window {nr}.
2700 When {nr} is zero, the width of the current window is
2701 returned. When window {nr} doesn't exist, -1 is returned.
2702 An existing window always has a width of zero or more.
2703 Examples: >
2704 :echo "The current window has " . winwidth(0) . " columns."
2705 :if winwidth(0) <= 50
2706 : exe "normal 50\<C-W>|"
2707 :endif
2708<
2709
2710 *feature-list*
2711There are three types of features:
27121. Features that are only supported when they have been enabled when Vim
2713 was compiled |+feature-list|. Example: >
2714 :if has("cindent")
27152. Features that are only supported when certain conditions have been met.
2716 Example: >
2717 :if has("gui_running")
2718< *has-patch*
27193. Included patches. First check |v:version| for the version of Vim.
2720 Then the "patch123" feature means that patch 123 has been included for
2721 this version. Example (checking version 6.2.148 or later): >
2722 :if v:version > 602 || v:version == 602 && has("patch148")
2723
2724all_builtin_terms Compiled with all builtin terminals enabled.
2725amiga Amiga version of Vim.
2726arabic Compiled with Arabic support |Arabic|.
2727arp Compiled with ARP support (Amiga).
2728autocmd Compiled with autocommands support.
2729balloon_eval Compiled with |balloon-eval| support.
2730beos BeOS version of Vim.
2731browse Compiled with |:browse| support, and browse() will
2732 work.
2733builtin_terms Compiled with some builtin terminals.
2734byte_offset Compiled with support for 'o' in 'statusline'
2735cindent Compiled with 'cindent' support.
2736clientserver Compiled with remote invocation support |clientserver|.
2737clipboard Compiled with 'clipboard' support.
2738cmdline_compl Compiled with |cmdline-completion| support.
2739cmdline_hist Compiled with |cmdline-history| support.
2740cmdline_info Compiled with 'showcmd' and 'ruler' support.
2741comments Compiled with |'comments'| support.
2742cryptv Compiled with encryption support |encryption|.
2743cscope Compiled with |cscope| support.
2744compatible Compiled to be very Vi compatible.
2745debug Compiled with "DEBUG" defined.
2746dialog_con Compiled with console dialog support.
2747dialog_gui Compiled with GUI dialog support.
2748diff Compiled with |vimdiff| and 'diff' support.
2749digraphs Compiled with support for digraphs.
2750dnd Compiled with support for the "~ register |quote_~|.
2751dos32 32 bits DOS (DJGPP) version of Vim.
2752dos16 16 bits DOS version of Vim.
2753ebcdic Compiled on a machine with ebcdic character set.
2754emacs_tags Compiled with support for Emacs tags.
2755eval Compiled with expression evaluation support. Always
2756 true, of course!
2757ex_extra Compiled with extra Ex commands |+ex_extra|.
2758extra_search Compiled with support for |'incsearch'| and
2759 |'hlsearch'|
2760farsi Compiled with Farsi support |farsi|.
2761file_in_path Compiled with support for |gf| and |<cfile>|
2762find_in_path Compiled with support for include file searches
2763 |+find_in_path|.
2764fname_case Case in file names matters (for Amiga, MS-DOS, and
2765 Windows this is not present).
2766folding Compiled with |folding| support.
2767footer Compiled with GUI footer support. |gui-footer|
2768fork Compiled to use fork()/exec() instead of system().
2769gettext Compiled with message translation |multi-lang|
2770gui Compiled with GUI enabled.
2771gui_athena Compiled with Athena GUI.
Bram Moolenaar69a7cb42004-06-20 12:51:53 +00002772gui_beos Compiled with BeOS GUI.
Bram Moolenaar071d4272004-06-13 20:20:40 +00002773gui_gtk Compiled with GTK+ GUI (any version).
2774gui_gtk2 Compiled with GTK+ 2 GUI (gui_gtk is also defined).
Bram Moolenaar843ee412004-06-30 16:16:41 +00002775gui_kde Compiled with KDE GUI |KVim|
Bram Moolenaar071d4272004-06-13 20:20:40 +00002776gui_mac Compiled with Macintosh GUI.
2777gui_motif Compiled with Motif GUI.
2778gui_photon Compiled with Photon GUI.
2779gui_win32 Compiled with MS Windows Win32 GUI.
2780gui_win32s idem, and Win32s system being used (Windows 3.1)
2781gui_running Vim is running in the GUI, or it will start soon.
2782hangul_input Compiled with Hangul input support. |hangul|
2783iconv Can use iconv() for conversion.
2784insert_expand Compiled with support for CTRL-X expansion commands in
2785 Insert mode.
2786jumplist Compiled with |jumplist| support.
2787keymap Compiled with 'keymap' support.
2788langmap Compiled with 'langmap' support.
2789libcall Compiled with |libcall()| support.
2790linebreak Compiled with 'linebreak', 'breakat' and 'showbreak'
2791 support.
2792lispindent Compiled with support for lisp indenting.
2793listcmds Compiled with commands for the buffer list |:files|
2794 and the argument list |arglist|.
2795localmap Compiled with local mappings and abbr. |:map-local|
2796mac Macintosh version of Vim.
2797macunix Macintosh version of Vim, using Unix files (OS-X).
2798menu Compiled with support for |:menu|.
2799mksession Compiled with support for |:mksession|.
2800modify_fname Compiled with file name modifiers. |filename-modifiers|
2801mouse Compiled with support mouse.
2802mouseshape Compiled with support for 'mouseshape'.
2803mouse_dec Compiled with support for Dec terminal mouse.
2804mouse_gpm Compiled with support for gpm (Linux console mouse)
2805mouse_netterm Compiled with support for netterm mouse.
2806mouse_pterm Compiled with support for qnx pterm mouse.
2807mouse_xterm Compiled with support for xterm mouse.
2808multi_byte Compiled with support for editing Korean et al.
2809multi_byte_ime Compiled with support for IME input method.
2810multi_lang Compiled with support for multiple languages.
2811netbeans_intg Compiled with support for |netbeans|.
2812ole Compiled with OLE automation support for Win32.
2813os2 OS/2 version of Vim.
2814osfiletype Compiled with support for osfiletypes |+osfiletype|
2815path_extra Compiled with up/downwards search in 'path' and 'tags'
2816perl Compiled with Perl interface.
2817postscript Compiled with PostScript file printing.
2818printer Compiled with |:hardcopy| support.
2819python Compiled with Python interface.
2820qnx QNX version of Vim.
2821quickfix Compiled with |quickfix| support.
2822rightleft Compiled with 'rightleft' support.
2823ruby Compiled with Ruby interface |ruby|.
2824scrollbind Compiled with 'scrollbind' support.
2825showcmd Compiled with 'showcmd' support.
2826signs Compiled with |:sign| support.
2827smartindent Compiled with 'smartindent' support.
Bram Moolenaar69a7cb42004-06-20 12:51:53 +00002828sniff Compiled with SNiFF interface support.
Bram Moolenaar071d4272004-06-13 20:20:40 +00002829statusline Compiled with support for 'statusline', 'rulerformat'
2830 and special formats of 'titlestring' and 'iconstring'.
2831sun_workshop Compiled with support for Sun |workshop|.
2832syntax Compiled with syntax highlighting support.
2833syntax_items There are active syntax highlighting items for the
2834 current buffer.
2835system Compiled to use system() instead of fork()/exec().
2836tag_binary Compiled with binary searching in tags files
2837 |tag-binary-search|.
2838tag_old_static Compiled with support for old static tags
2839 |tag-old-static|.
2840tag_any_white Compiled with support for any white characters in tags
2841 files |tag-any-white|.
2842tcl Compiled with Tcl interface.
2843terminfo Compiled with terminfo instead of termcap.
2844termresponse Compiled with support for |t_RV| and |v:termresponse|.
2845textobjects Compiled with support for |text-objects|.
2846tgetent Compiled with tgetent support, able to use a termcap
2847 or terminfo file.
2848title Compiled with window title support |'title'|.
2849toolbar Compiled with support for |gui-toolbar|.
2850unix Unix version of Vim.
2851user_commands User-defined commands.
2852viminfo Compiled with viminfo support.
2853vim_starting True while initial source'ing takes place.
2854vertsplit Compiled with vertically split windows |:vsplit|.
2855virtualedit Compiled with 'virtualedit' option.
2856visual Compiled with Visual mode.
2857visualextra Compiled with extra Visual mode commands.
2858 |blockwise-operators|.
2859vms VMS version of Vim.
2860vreplace Compiled with |gR| and |gr| commands.
2861wildignore Compiled with 'wildignore' option.
2862wildmenu Compiled with 'wildmenu' option.
2863windows Compiled with support for more than one window.
2864winaltkeys Compiled with 'winaltkeys' option.
2865win16 Win16 version of Vim (MS-Windows 3.1).
2866win32 Win32 version of Vim (MS-Windows 95/98/ME/NT/2000/XP).
2867win64 Win64 version of Vim (MS-Windows 64 bit).
2868win32unix Win32 version of Vim, using Unix files (Cygwin)
2869win95 Win32 version for MS-Windows 95/98/ME.
2870writebackup Compiled with 'writebackup' default on.
2871xfontset Compiled with X fontset support |xfontset|.
2872xim Compiled with X input method support |xim|.
2873xsmp Compiled with X session management support.
2874xsmp_interact Compiled with interactive X session management support.
2875xterm_clipboard Compiled with support for xterm clipboard.
2876xterm_save Compiled with support for saving and restoring the
2877 xterm screen.
2878x11 Compiled with X11 support.
2879
2880 *string-match*
2881Matching a pattern in a String
2882
2883A regexp pattern as explained at |pattern| is normally used to find a match in
2884the buffer lines. When a pattern is used to find a match in a String, almost
2885everything works in the same way. The difference is that a String is handled
2886like it is one line. When it contains a "\n" character, this is not seen as a
2887line break for the pattern. It can be matched with a "\n" in the pattern, or
2888with ".". Example: >
2889 :let a = "aaaa\nxxxx"
2890 :echo matchstr(a, "..\n..")
2891 aa
2892 xx
2893 :echo matchstr(a, "a.x")
2894 a
2895 x
2896
2897Don't forget that "^" will only match at the first character of the String and
2898"$" at the last character of the string. They don't match after or before a
2899"\n".
2900
2901==============================================================================
29025. Defining functions *user-functions*
2903
2904New functions can be defined. These can be called just like builtin
2905functions. The function executes a sequence of Ex commands. Normal mode
2906commands can be executed with the |:normal| command.
2907
2908The function name must start with an uppercase letter, to avoid confusion with
2909builtin functions. To prevent from using the same name in different scripts
2910avoid obvious, short names. A good habit is to start the function name with
2911the name of the script, e.g., "HTMLcolor()".
2912
2913It's also possible to use curly braces, see |curly-braces-names|.
2914
2915 *local-function*
2916A function local to a script must start with "s:". A local script function
2917can only be called from within the script and from functions, user commands
2918and autocommands defined in the script. It is also possible to call the
2919function from a mappings defined in the script, but then |<SID>| must be used
2920instead of "s:" when the mapping is expanded outside of the script.
2921
2922 *:fu* *:function* *E128* *E129* *E123*
2923:fu[nction] List all functions and their arguments.
2924
2925:fu[nction] {name} List function {name}.
2926 *E124* *E125*
2927:fu[nction][!] {name}([arguments]) [range] [abort]
2928 Define a new function by the name {name}. The name
2929 must be made of alphanumeric characters and '_', and
2930 must start with a capital or "s:" (see above).
2931 *function-argument* *a:var*
2932 An argument can be defined by giving its name. In the
2933 function this can then be used as "a:name" ("a:" for
2934 argument).
2935 Up to 20 arguments can be given, separated by commas.
2936 Finally, an argument "..." can be specified, which
2937 means that more arguments may be following. In the
2938 function they can be used as "a:1", "a:2", etc. "a:0"
2939 is set to the number of extra arguments (which can be
2940 0).
2941 When not using "...", the number of arguments in a
2942 function call must be equal to the number of named
2943 arguments. When using "...", the number of arguments
2944 may be larger.
2945 It is also possible to define a function without any
2946 arguments. You must still supply the () then.
2947 The body of the function follows in the next lines,
2948 until the matching |:endfunction|. It is allowed to
2949 define another function inside a function body.
2950 *E127* *E122*
2951 When a function by this name already exists and [!] is
2952 not used an error message is given. When [!] is used,
2953 an existing function is silently replaced. Unless it
2954 is currently being executed, that is an error.
2955 *a:firstline* *a:lastline*
2956 When the [range] argument is added, the function is
2957 expected to take care of a range itself. The range is
2958 passed as "a:firstline" and "a:lastline". If [range]
2959 is excluded, ":{range}call" will call the function for
2960 each line in the range, with the cursor on the start
2961 of each line. See |function-range-example|.
2962 When the [abort] argument is added, the function will
2963 abort as soon as an error is detected.
2964 The last used search pattern and the redo command "."
2965 will not be changed by the function.
2966
2967 *:endf* *:endfunction* *E126* *E193*
2968:endf[unction] The end of a function definition. Must be on a line
2969 by its own, without other commands.
2970
2971 *:delf* *:delfunction* *E130* *E131*
2972:delf[unction] {name} Delete function {name}.
2973
2974 *:retu* *:return* *E133*
2975:retu[rn] [expr] Return from a function. When "[expr]" is given, it is
2976 evaluated and returned as the result of the function.
2977 If "[expr]" is not given, the number 0 is returned.
2978 When a function ends without an explicit ":return",
2979 the number 0 is returned.
2980 Note that there is no check for unreachable lines,
2981 thus there is no warning if commands follow ":return".
2982
2983 If the ":return" is used after a |:try| but before the
2984 matching |:finally| (if present), the commands
2985 following the ":finally" up to the matching |:endtry|
2986 are executed first. This process applies to all
2987 nested ":try"s inside the function. The function
2988 returns at the outermost ":endtry".
2989
2990
2991Inside a function variables can be used. These are local variables, which
2992will disappear when the function returns. Global variables need to be
2993accessed with "g:".
2994
2995Example: >
2996 :function Table(title, ...)
2997 : echohl Title
2998 : echo a:title
2999 : echohl None
3000 : let idx = 1
3001 : while idx <= a:0
3002 : echo a:{idx} . ' '
3003 : let idx = idx + 1
3004 : endwhile
3005 : return idx
3006 :endfunction
3007
3008This function can then be called with: >
3009 let lines = Table("Table", "line1", "line2")
3010 let lines = Table("Empty Table")
3011
3012To return more than one value, pass the name of a global variable: >
3013 :function Compute(n1, n2, divname)
3014 : if a:n2 == 0
3015 : return "fail"
3016 : endif
3017 : let g:{a:divname} = a:n1 / a:n2
3018 : return "ok"
3019 :endfunction
3020
3021This function can then be called with: >
3022 :let success = Compute(13, 1324, "div")
3023 :if success == "ok"
3024 : echo div
3025 :endif
3026
3027An alternative is to return a command that can be executed. This also works
3028with local variables in a calling function. Example: >
3029 :function Foo()
3030 : execute Bar()
3031 : echo "line " . lnum . " column " . col
3032 :endfunction
3033
3034 :function Bar()
3035 : return "let lnum = " . line(".") . " | let col = " . col(".")
3036 :endfunction
3037
3038The names "lnum" and "col" could also be passed as argument to Bar(), to allow
3039the caller to set the names.
3040
3041 *:cal* *:call* *E107*
3042:[range]cal[l] {name}([arguments])
3043 Call a function. The name of the function and its arguments
3044 are as specified with |:function|. Up to 20 arguments can be
3045 used.
3046 Without a range and for functions that accept a range, the
3047 function is called once. When a range is given the cursor is
3048 positioned at the start of the first line before executing the
3049 function.
3050 When a range is given and the function doesn't handle it
3051 itself, the function is executed for each line in the range,
3052 with the cursor in the first column of that line. The cursor
3053 is left at the last line (possibly moved by the last function
3054 call). The arguments are re-evaluated for each line. Thus
3055 this works:
3056 *function-range-example* >
3057 :function Mynumber(arg)
3058 : echo line(".") . " " . a:arg
3059 :endfunction
3060 :1,5call Mynumber(getline("."))
3061<
3062 The "a:firstline" and "a:lastline" are defined anyway, they
3063 can be used to do something different at the start or end of
3064 the range.
3065
3066 Example of a function that handles the range itself: >
3067
3068 :function Cont() range
3069 : execute (a:firstline + 1) . "," . a:lastline . 's/^/\t\\ '
3070 :endfunction
3071 :4,8call Cont()
3072<
3073 This function inserts the continuation character "\" in front
3074 of all the lines in the range, except the first one.
3075
3076 *E132*
3077The recursiveness of user functions is restricted with the |'maxfuncdepth'|
3078option.
3079
3080 *autoload-functions*
3081When using many or large functions, it's possible to automatically define them
3082only when they are used. Use the FuncUndefined autocommand event with a
3083pattern that matches the function(s) to be defined. Example: >
3084
3085 :au FuncUndefined BufNet* source ~/vim/bufnetfuncs.vim
3086
3087The file "~/vim/bufnetfuncs.vim" should then define functions that start with
3088"BufNet". Also see |FuncUndefined|.
3089
3090==============================================================================
30916. Curly braces names *curly-braces-names*
3092
3093Wherever you can use a variable, you can use a "curly braces name" variable.
3094This is a regular variable name with one or more expressions wrapped in braces
3095{} like this: >
3096 my_{adjective}_variable
3097
3098When Vim encounters this, it evaluates the expression inside the braces, puts
3099that in place of the expression, and re-interprets the whole as a variable
3100name. So in the above example, if the variable "adjective" was set to
3101"noisy", then the reference would be to "my_noisy_variable", whereas if
3102"adjective" was set to "quiet", then it would be to "my_quiet_variable".
3103
3104One application for this is to create a set of variables governed by an option
3105value. For example, the statement >
3106 echo my_{&background}_message
3107
3108would output the contents of "my_dark_message" or "my_light_message" depending
3109on the current value of 'background'.
3110
3111You can use multiple brace pairs: >
3112 echo my_{adverb}_{adjective}_message
3113..or even nest them: >
3114 echo my_{ad{end_of_word}}_message
3115where "end_of_word" is either "verb" or "jective".
3116
3117However, the expression inside the braces must evaluate to a valid single
3118variable name. e.g. this is invalid: >
3119 :let foo='a + b'
3120 :echo c{foo}d
3121.. since the result of expansion is "ca + bd", which is not a variable name.
3122
3123 *curly-braces-function-names*
3124You can call and define functions by an evaluated name in a similar way.
3125Example: >
3126 :let func_end='whizz'
3127 :call my_func_{func_end}(parameter)
3128
3129This would call the function "my_func_whizz(parameter)".
3130
3131==============================================================================
31327. Commands *expression-commands*
3133
3134:let {var-name} = {expr1} *:let* *E18*
3135 Set internal variable {var-name} to the result of the
3136 expression {expr1}. The variable will get the type
3137 from the {expr}. If {var-name} didn't exist yet, it
3138 is created.
3139
3140:let ${env-name} = {expr1} *:let-environment* *:let-$*
3141 Set environment variable {env-name} to the result of
3142 the expression {expr1}. The type is always String.
3143
3144:let @{reg-name} = {expr1} *:let-register* *:let-@*
3145 Write the result of the expression {expr1} in register
3146 {reg-name}. {reg-name} must be a single letter, and
3147 must be the name of a writable register (see
3148 |registers|). "@@" can be used for the unnamed
3149 register, "@/" for the search pattern.
3150 If the result of {expr1} ends in a <CR> or <NL>, the
3151 register will be linewise, otherwise it will be set to
3152 characterwise.
3153 This can be used to clear the last search pattern: >
3154 :let @/ = ""
3155< This is different from searching for an empty string,
3156 that would match everywhere.
3157
3158:let &{option-name} = {expr1} *:let-option* *:let-star*
3159 Set option {option-name} to the result of the
3160 expression {expr1}. The value is always converted to
3161 the type of the option.
3162 For an option local to a window or buffer the effect
3163 is just like using the |:set| command: both the local
3164 value and the global value is changed.
3165
3166:let &l:{option-name} = {expr1}
3167 Like above, but only set the local value of an option
3168 (if there is one). Works like |:setlocal|.
3169
3170:let &g:{option-name} = {expr1}
3171 Like above, but only set the global value of an option
3172 (if there is one). Works like |:setglobal|.
3173
3174 *E106*
3175:let {var-name} .. List the value of variable {var-name}. Several
3176 variable names may be given.
3177
3178:let List the values of all variables.
3179
3180 *:unlet* *:unl* *E108*
3181:unl[et][!] {var-name} ...
3182 Remove the internal variable {var-name}. Several
3183 variable names can be given, they are all removed.
3184 With [!] no error message is given for non-existing
3185 variables.
3186
3187:if {expr1} *:if* *:endif* *:en* *E171* *E579* *E580*
3188:en[dif] Execute the commands until the next matching ":else"
3189 or ":endif" if {expr1} evaluates to non-zero.
3190
3191 From Vim version 4.5 until 5.0, every Ex command in
3192 between the ":if" and ":endif" is ignored. These two
3193 commands were just to allow for future expansions in a
3194 backwards compatible way. Nesting was allowed. Note
3195 that any ":else" or ":elseif" was ignored, the "else"
3196 part was not executed either.
3197
3198 You can use this to remain compatible with older
3199 versions: >
3200 :if version >= 500
3201 : version-5-specific-commands
3202 :endif
3203< The commands still need to be parsed to find the
3204 "endif". Sometimes an older Vim has a problem with a
3205 new command. For example, ":silent" is recognized as
3206 a ":substitute" command. In that case ":execute" can
3207 avoid problems: >
3208 :if version >= 600
3209 : execute "silent 1,$delete"
3210 :endif
3211<
3212 NOTE: The ":append" and ":insert" commands don't work
3213 properly in between ":if" and ":endif".
3214
3215 *:else* *:el* *E581* *E583*
3216:el[se] Execute the commands until the next matching ":else"
3217 or ":endif" if they previously were not being
3218 executed.
3219
3220 *:elseif* *:elsei* *E582* *E584*
3221:elsei[f] {expr1} Short for ":else" ":if", with the addition that there
3222 is no extra ":endif".
3223
3224:wh[ile] {expr1} *:while* *:endwhile* *:wh* *:endw*
3225 *E170* *E585* *E588*
3226:endw[hile] Repeat the commands between ":while" and ":endwhile",
3227 as long as {expr1} evaluates to non-zero.
3228 When an error is detected from a command inside the
3229 loop, execution continues after the "endwhile".
3230
3231 NOTE: The ":append" and ":insert" commands don't work
3232 properly inside a ":while" loop.
3233
3234 *:continue* *:con* *E586*
3235:con[tinue] When used inside a ":while", jumps back to the
3236 ":while". If it is used after a |:try| inside the
3237 ":while" but before the matching |:finally| (if
3238 present), the commands following the ":finally" up to
3239 the matching |:endtry| are executed first. This
3240 process applies to all nested ":try"s inside the
3241 ":while". The outermost ":endtry" then jumps back to
3242 the ":while".
3243
3244 *:break* *:brea* *E587*
3245:brea[k] When used inside a ":while", skips to the command
3246 after the matching ":endwhile". If it is used after
3247 a |:try| inside the ":while" but before the matching
3248 |:finally| (if present), the commands following the
3249 ":finally" up to the matching |:endtry| are executed
3250 first. This process applies to all nested ":try"s
3251 inside the ":while". The outermost ":endtry" then
3252 jumps to the command after the ":endwhile".
3253
3254:try *:try* *:endt* *:endtry* *E600* *E601* *E602*
3255:endt[ry] Change the error handling for the commands between
3256 ":try" and ":endtry" including everything being
3257 executed across ":source" commands, function calls,
3258 or autocommand invocations.
3259
3260 When an error or interrupt is detected and there is
3261 a |:finally| command following, execution continues
3262 after the ":finally". Otherwise, or when the
3263 ":endtry" is reached thereafter, the next
3264 (dynamically) surrounding ":try" is checked for
3265 a corresponding ":finally" etc. Then the script
3266 processing is terminated. (Whether a function
3267 definition has an "abort" argument does not matter.)
3268 Example: >
3269 :try | edit too much | finally | echo "cleanup" | endtry
3270 :echo "impossible" " not reached, script terminated above
3271<
3272 Moreover, an error or interrupt (dynamically) inside
3273 ":try" and ":endtry" is converted to an exception. It
3274 can be caught as if it were thrown by a |:throw|
3275 command (see |:catch|). In this case, the script
3276 processing is not terminated.
3277
3278 The value "Vim:Interrupt" is used for an interrupt
3279 exception. An error in a Vim command is converted
3280 to a value of the form "Vim({command}):{errmsg}",
3281 other errors are converted to a value of the form
3282 "Vim:{errmsg}". {command} is the full command name,
3283 and {errmsg} is the message that is displayed if the
3284 error exception is not caught, always beginning with
3285 the error number.
3286 Examples: >
3287 :try | sleep 100 | catch /^Vim:Interrupt$/ | endtry
3288 :try | edit | catch /^Vim(edit):E\d\+/ | echo "error" | endtry
3289<
3290 *:cat* *:catch* *E603* *E604* *E605*
3291:cat[ch] /{pattern}/ The following commands until the next ":catch",
3292 |:finally|, or |:endtry| that belongs to the same
3293 |:try| as the ":catch" are executed when an exception
3294 matching {pattern} is being thrown and has not yet
3295 been caught by a previous ":catch". Otherwise, these
3296 commands are skipped.
3297 When {pattern} is omitted all errors are caught.
3298 Examples: >
3299 :catch /^Vim:Interrupt$/ " catch interrupts (CTRL-C)
3300 :catch /^Vim\%((\a\+)\)\=:E/ " catch all Vim errors
3301 :catch /^Vim\%((\a\+)\)\=:/ " catch errors and interrupts
3302 :catch /^Vim(write):/ " catch all errors in :write
3303 :catch /^Vim\%((\a\+)\)\=:E123/ " catch error E123
3304 :catch /my-exception/ " catch user exception
3305 :catch /.*/ " catch everything
3306 :catch " same as /.*/
3307<
3308 Another character can be used instead of / around the
3309 {pattern}, so long as it does not have a special
3310 meaning (e.g., '|' or '"') and doesn't occur inside
3311 {pattern}.
3312 NOTE: It is not reliable to ":catch" the TEXT of
3313 an error message because it may vary in different
3314 locales.
3315
3316 *:fina* *:finally* *E606* *E607*
3317:fina[lly] The following commands until the matching |:endtry|
3318 are executed whenever the part between the matching
3319 |:try| and the ":finally" is left: either by falling
3320 through to the ":finally" or by a |:continue|,
3321 |:break|, |:finish|, or |:return|, or by an error or
3322 interrupt or exception (see |:throw|).
3323
3324 *:th* *:throw* *E608*
3325:th[row] {expr1} The {expr1} is evaluated and thrown as an exception.
3326 If the ":throw" is used after a |:try| but before the
3327 first corresponding |:catch|, commands are skipped
3328 until the first ":catch" matching {expr1} is reached.
3329 If there is no such ":catch" or if the ":throw" is
3330 used after a ":catch" but before the |:finally|, the
3331 commands following the ":finally" (if present) up to
3332 the matching |:endtry| are executed. If the ":throw"
3333 is after the ":finally", commands up to the ":endtry"
3334 are skipped. At the ":endtry", this process applies
3335 again for the next dynamically surrounding ":try"
3336 (which may be found in a calling function or sourcing
3337 script), until a matching ":catch" has been found.
3338 If the exception is not caught, the command processing
3339 is terminated.
3340 Example: >
3341 :try | throw "oops" | catch /^oo/ | echo "caught" | endtry
3342<
3343
3344 *:ec* *:echo*
3345:ec[ho] {expr1} .. Echoes each {expr1}, with a space in between. The
3346 first {expr1} starts on a new line.
3347 Also see |:comment|.
3348 Use "\n" to start a new line. Use "\r" to move the
3349 cursor to the first column.
3350 Uses the highlighting set by the |:echohl| command.
3351 Cannot be followed by a comment.
3352 Example: >
3353 :echo "the value of 'shell' is" &shell
3354< A later redraw may make the message disappear again.
3355 To avoid that a command from before the ":echo" causes
3356 a redraw afterwards (redraws are often postponed until
3357 you type something), force a redraw with the |:redraw|
3358 command. Example: >
3359 :new | redraw | echo "there is a new window"
3360<
3361 *:echon*
3362:echon {expr1} .. Echoes each {expr1}, without anything added. Also see
3363 |:comment|.
3364 Uses the highlighting set by the |:echohl| command.
3365 Cannot be followed by a comment.
3366 Example: >
3367 :echon "the value of 'shell' is " &shell
3368<
3369 Note the difference between using ":echo", which is a
3370 Vim command, and ":!echo", which is an external shell
3371 command: >
3372 :!echo % --> filename
3373< The arguments of ":!" are expanded, see |:_%|. >
3374 :!echo "%" --> filename or "filename"
3375< Like the previous example. Whether you see the double
3376 quotes or not depends on your 'shell'. >
3377 :echo % --> nothing
3378< The '%' is an illegal character in an expression. >
3379 :echo "%" --> %
3380< This just echoes the '%' character. >
3381 :echo expand("%") --> filename
3382< This calls the expand() function to expand the '%'.
3383
3384 *:echoh* *:echohl*
3385:echoh[l] {name} Use the highlight group {name} for the following
3386 |:echo|, |:echon| and |:echomsg| commands. Also used
3387 for the |input()| prompt. Example: >
3388 :echohl WarningMsg | echo "Don't panic!" | echohl None
3389< Don't forget to set the group back to "None",
3390 otherwise all following echo's will be highlighted.
3391
3392 *:echom* *:echomsg*
3393:echom[sg] {expr1} .. Echo the expression(s) as a true message, saving the
3394 message in the |message-history|.
3395 Spaces are placed between the arguments as with the
3396 |:echo| command. But unprintable characters are
3397 displayed, not interpreted.
3398 Uses the highlighting set by the |:echohl| command.
3399 Example: >
3400 :echomsg "It's a Zizzer Zazzer Zuzz, as you can plainly see."
3401<
3402 *:echoe* *:echoerr*
3403:echoe[rr] {expr1} .. Echo the expression(s) as an error message, saving the
3404 message in the |message-history|. When used in a
3405 script or function the line number will be added.
3406 Spaces are placed between the arguments as with the
3407 :echo command. When used inside a try conditional,
3408 the message is raised as an error exception instead
3409 (see |try-echoerr|).
3410 Example: >
3411 :echoerr "This script just failed!"
3412< If you just want a highlighted message use |:echohl|.
3413 And to get a beep: >
3414 :exe "normal \<Esc>"
3415<
3416 *:exe* *:execute*
3417:exe[cute] {expr1} .. Executes the string that results from the evaluation
3418 of {expr1} as an Ex command. Multiple arguments are
3419 concatenated, with a space in between. {expr1} is
3420 used as the processed command, command line editing
3421 keys are not recognized.
3422 Cannot be followed by a comment.
3423 Examples: >
3424 :execute "buffer " nextbuf
3425 :execute "normal " count . "w"
3426<
3427 ":execute" can be used to append a command to commands
3428 that don't accept a '|'. Example: >
3429 :execute '!ls' | echo "theend"
3430
3431< ":execute" is also a nice way to avoid having to type
3432 control characters in a Vim script for a ":normal"
3433 command: >
3434 :execute "normal ixxx\<Esc>"
3435< This has an <Esc> character, see |expr-string|.
3436
3437 Note: The executed string may be any command-line, but
3438 you cannot start or end a "while" or "if" command.
3439 Thus this is illegal: >
3440 :execute 'while i > 5'
3441 :execute 'echo "test" | break'
3442<
3443 It is allowed to have a "while" or "if" command
3444 completely in the executed string: >
3445 :execute 'while i < 5 | echo i | let i = i + 1 | endwhile'
3446<
3447
3448 *:comment*
3449 ":execute", ":echo" and ":echon" cannot be followed by
3450 a comment directly, because they see the '"' as the
3451 start of a string. But, you can use '|' followed by a
3452 comment. Example: >
3453 :echo "foo" | "this is a comment
3454
3455==============================================================================
34568. Exception handling *exception-handling*
3457
3458The Vim script language comprises an exception handling feature. This section
3459explains how it can be used in a Vim script.
3460
3461Exceptions may be raised by Vim on an error or on interrupt, see
3462|catch-errors| and |catch-interrupt|. You can also explicitly throw an
3463exception by using the ":throw" command, see |throw-catch|.
3464
3465
3466TRY CONDITIONALS *try-conditionals*
3467
3468Exceptions can be caught or can cause cleanup code to be executed. You can
3469use a try conditional to specify catch clauses (that catch exceptions) and/or
3470a finally clause (to be executed for cleanup).
3471 A try conditional begins with a |:try| command and ends at the matching
3472|:endtry| command. In between, you can use a |:catch| command to start
3473a catch clause, or a |:finally| command to start a finally clause. There may
3474be none or multiple catch clauses, but there is at most one finally clause,
3475which must not be followed by any catch clauses. The lines before the catch
3476clauses and the finally clause is called a try block. >
3477
3478 :try
3479 : ...
3480 : ... TRY BLOCK
3481 : ...
3482 :catch /{pattern}/
3483 : ...
3484 : ... CATCH CLAUSE
3485 : ...
3486 :catch /{pattern}/
3487 : ...
3488 : ... CATCH CLAUSE
3489 : ...
3490 :finally
3491 : ...
3492 : ... FINALLY CLAUSE
3493 : ...
3494 :endtry
3495
3496The try conditional allows to watch code for exceptions and to take the
3497appropriate actions. Exceptions from the try block may be caught. Exceptions
3498from the try block and also the catch clauses may cause cleanup actions.
3499 When no exception is thrown during execution of the try block, the control
3500is transferred to the finally clause, if present. After its execution, the
3501script continues with the line following the ":endtry".
3502 When an exception occurs during execution of the try block, the remaining
3503lines in the try block are skipped. The exception is matched against the
3504patterns specified as arguments to the ":catch" commands. The catch clause
3505after the first matching ":catch" is taken, other catch clauses are not
3506executed. The catch clause ends when the next ":catch", ":finally", or
3507":endtry" command is reached - whatever is first. Then, the finally clause
3508(if present) is executed. When the ":endtry" is reached, the script execution
3509continues in the following line as usual.
3510 When an exception that does not match any of the patterns specified by the
3511":catch" commands is thrown in the try block, the exception is not caught by
3512that try conditional and none of the catch clauses is executed. Only the
3513finally clause, if present, is taken. The exception pends during execution of
3514the finally clause. It is resumed at the ":endtry", so that commands after
3515the ":endtry" are not executed and the exception might be caught elsewhere,
3516see |try-nesting|.
3517 When during execution of a catch clause another exception is thrown, the
3518remaining lines in that catch clause are not executed. The new exception is
3519not matched against the patterns in any of the ":catch" commands of the same
3520try conditional and none of its catch clauses is taken. If there is, however,
3521a finally clause, it is executed, and the exception pends during its
3522execution. The commands following the ":endtry" are not executed. The new
3523exception might, however, be caught elsewhere, see |try-nesting|.
3524 When during execution of the finally clause (if present) an exception is
3525thrown, the remaining lines in the finally clause are skipped. If the finally
3526clause has been taken because of an exception from the try block or one of the
3527catch clauses, the original (pending) exception is discarded. The commands
3528following the ":endtry" are not executed, and the exception from the finally
3529clause is propagated and can be caught elsewhere, see |try-nesting|.
3530
3531The finally clause is also executed, when a ":break" or ":continue" for
3532a ":while" loop enclosing the complete try conditional is executed from the
3533try block or a catch clause. Or when a ":return" or ":finish" is executed
3534from the try block or a catch clause of a try conditional in a function or
3535sourced script, respectively. The ":break", ":continue", ":return", or
3536":finish" pends during execution of the finally clause and is resumed when the
3537":endtry" is reached. It is, however, discarded when an exception is thrown
3538from the finally clause.
3539 When a ":break" or ":continue" for a ":while" loop enclosing the complete
3540try conditional or when a ":return" or ":finish" is encountered in the finally
3541clause, the rest of the finally clause is skipped, and the ":break",
3542":continue", ":return" or ":finish" is executed as usual. If the finally
3543clause has been taken because of an exception or an earlier ":break",
3544":continue", ":return", or ":finish" from the try block or a catch clause,
3545this pending exception or command is discarded.
3546
3547For examples see |throw-catch| and |try-finally|.
3548
3549
3550NESTING OF TRY CONDITIONALS *try-nesting*
3551
3552Try conditionals can be nested arbitrarily. That is, a complete try
3553conditional can be put into the try block, a catch clause, or the finally
3554clause of another try conditional. If the inner try conditional does not
3555catch an exception thrown in its try block or throws a new exception from one
3556of its catch clauses or its finally clause, the outer try conditional is
3557checked according to the rules above. If the inner try conditional is in the
3558try block of the outer try conditional, its catch clauses are checked, but
3559otherwise only the finally clause is executed. It does not matter for
3560nesting, whether the inner try conditional is directly contained in the outer
3561one, or whether the outer one sources a script or calls a function containing
3562the inner try conditional.
3563
3564When none of the active try conditionals catches an exception, just their
3565finally clauses are executed. Thereafter, the script processing terminates.
3566An error message is displayed in case of an uncaught exception explicitly
3567thrown by a ":throw" command. For uncaught error and interrupt exceptions
3568implicitly raised by Vim, the error message(s) or interrupt message are shown
3569as usual.
3570
3571For examples see |throw-catch|.
3572
3573
3574EXAMINING EXCEPTION HANDLING CODE *except-examine*
3575
3576Exception handling code can get tricky. If you are in doubt what happens, set
3577'verbose' to 13 or use the ":13verbose" command modifier when sourcing your
3578script file. Then you see when an exception is thrown, discarded, caught, or
3579finished. When using a verbosity level of at least 14, things pending in
3580a finally clause are also shown. This information is also given in debug mode
3581(see |debug-scripts|).
3582
3583
3584THROWING AND CATCHING EXCEPTIONS *throw-catch*
3585
3586You can throw any number or string as an exception. Use the |:throw| command
3587and pass the value to be thrown as argument: >
3588 :throw 4711
3589 :throw "string"
3590< *throw-expression*
3591You can also specify an expression argument. The expression is then evaluated
3592first, and the result is thrown: >
3593 :throw 4705 + strlen("string")
3594 :throw strpart("strings", 0, 6)
3595
3596An exception might be thrown during evaluation of the argument of the ":throw"
3597command. Unless it is caught there, the expression evaluation is abandoned.
3598The ":throw" command then does not throw a new exception.
3599 Example: >
3600
3601 :function! Foo(arg)
3602 : try
3603 : throw a:arg
3604 : catch /foo/
3605 : endtry
3606 : return 1
3607 :endfunction
3608 :
3609 :function! Bar()
3610 : echo "in Bar"
3611 : return 4710
3612 :endfunction
3613 :
3614 :throw Foo("arrgh") + Bar()
3615
3616This throws "arrgh", and "in Bar" is not displayed since Bar() is not
3617executed. >
3618 :throw Foo("foo") + Bar()
3619however displays "in Bar" and throws 4711.
3620
3621Any other command that takes an expression as argument might also be
3622abandoned by an (uncaught) exception during the expression evaluation. The
3623exception is then propagated to the caller of the command.
3624 Example: >
3625
3626 :if Foo("arrgh")
3627 : echo "then"
3628 :else
3629 : echo "else"
3630 :endif
3631
3632Here neither of "then" or "else" is displayed.
3633
3634 *catch-order*
3635Exceptions can be caught by a try conditional with one or more |:catch|
3636commands, see |try-conditionals|. The values to be caught by each ":catch"
3637command can be specified as a pattern argument. The subsequent catch clause
3638gets executed when a matching exception is caught.
3639 Example: >
3640
3641 :function! Foo(value)
3642 : try
3643 : throw a:value
3644 : catch /^\d\+$/
3645 : echo "Number thrown"
3646 : catch /.*/
3647 : echo "String thrown"
3648 : endtry
3649 :endfunction
3650 :
3651 :call Foo(0x1267)
3652 :call Foo('string')
3653
3654The first call to Foo() displays "Number thrown", the second "String thrown".
3655An exception is matched against the ":catch" commands in the order they are
3656specified. Only the first match counts. So you should place the more
3657specific ":catch" first. The following order does not make sense: >
3658
3659 : catch /.*/
3660 : echo "String thrown"
3661 : catch /^\d\+$/
3662 : echo "Number thrown"
3663
3664The first ":catch" here matches always, so that the second catch clause is
3665never taken.
3666
3667 *throw-variables*
3668If you catch an exception by a general pattern, you may access the exact value
3669in the variable |v:exception|: >
3670
3671 : catch /^\d\+$/
3672 : echo "Number thrown. Value is" v:exception
3673
3674You may also be interested where an exception was thrown. This is stored in
3675|v:throwpoint|. Note that "v:exception" and "v:throwpoint" are valid for the
3676exception most recently caught as long it is not finished.
3677 Example: >
3678
3679 :function! Caught()
3680 : if v:exception != ""
3681 : echo 'Caught "' . v:exception . '" in ' . v:throwpoint
3682 : else
3683 : echo 'Nothing caught'
3684 : endif
3685 :endfunction
3686 :
3687 :function! Foo()
3688 : try
3689 : try
3690 : try
3691 : throw 4711
3692 : finally
3693 : call Caught()
3694 : endtry
3695 : catch /.*/
3696 : call Caught()
3697 : throw "oops"
3698 : endtry
3699 : catch /.*/
3700 : call Caught()
3701 : finally
3702 : call Caught()
3703 : endtry
3704 :endfunction
3705 :
3706 :call Foo()
3707
3708This displays >
3709
3710 Nothing caught
3711 Caught "4711" in function Foo, line 4
3712 Caught "oops" in function Foo, line 10
3713 Nothing caught
3714
3715A practical example: The following command ":LineNumber" displays the line
3716number in the script or function where it has been used: >
3717
3718 :function! LineNumber()
3719 : return substitute(v:throwpoint, '.*\D\(\d\+\).*', '\1', "")
3720 :endfunction
3721 :command! LineNumber try | throw "" | catch | echo LineNumber() | endtry
3722<
3723 *try-nested*
3724An exception that is not caught by a try conditional can be caught by
3725a surrounding try conditional: >
3726
3727 :try
3728 : try
3729 : throw "foo"
3730 : catch /foobar/
3731 : echo "foobar"
3732 : finally
3733 : echo "inner finally"
3734 : endtry
3735 :catch /foo/
3736 : echo "foo"
3737 :endtry
3738
3739The inner try conditional does not catch the exception, just its finally
3740clause is executed. The exception is then caught by the outer try
3741conditional. The example displays "inner finally" and then "foo".
3742
3743 *throw-from-catch*
3744You can catch an exception and throw a new one to be caught elsewhere from the
3745catch clause: >
3746
3747 :function! Foo()
3748 : throw "foo"
3749 :endfunction
3750 :
3751 :function! Bar()
3752 : try
3753 : call Foo()
3754 : catch /foo/
3755 : echo "Caught foo, throw bar"
3756 : throw "bar"
3757 : endtry
3758 :endfunction
3759 :
3760 :try
3761 : call Bar()
3762 :catch /.*/
3763 : echo "Caught" v:exception
3764 :endtry
3765
3766This displays "Caught foo, throw bar" and then "Caught bar".
3767
3768 *rethrow*
3769There is no real rethrow in the Vim script language, but you may throw
3770"v:exception" instead: >
3771
3772 :function! Bar()
3773 : try
3774 : call Foo()
3775 : catch /.*/
3776 : echo "Rethrow" v:exception
3777 : throw v:exception
3778 : endtry
3779 :endfunction
3780< *try-echoerr*
3781Note that this method cannot be used to "rethrow" Vim error or interrupt
3782exceptions, because it is not possible to fake Vim internal exceptions.
3783Trying so causes an error exception. You should throw your own exception
3784denoting the situation. If you want to cause a Vim error exception containing
3785the original error exception value, you can use the |:echoerr| command: >
3786
3787 :try
3788 : try
3789 : asdf
3790 : catch /.*/
3791 : echoerr v:exception
3792 : endtry
3793 :catch /.*/
3794 : echo v:exception
3795 :endtry
3796
3797This code displays
3798
3799 Vim(echoerr):Vim:E492: Not an editor command: asdf ~
3800
3801
3802CLEANUP CODE *try-finally*
3803
3804Scripts often change global settings and restore them at their end. If the
3805user however interrupts the script by pressing CTRL-C, the settings remain in
3806an inconsistent state. The same may happen to you in the development phase of
3807a script when an error occurs or you explicitly throw an exception without
3808catching it. You can solve these problems by using a try conditional with
3809a finally clause for restoring the settings. Its execution is guaranteed on
3810normal control flow, on error, on an explicit ":throw", and on interrupt.
3811(Note that errors and interrupts from inside the try conditional are converted
3812to exceptions. When not caught, they terminate the script after the finally
3813clause has been executed.)
3814Example: >
3815
3816 :try
3817 : let s:saved_ts = &ts
3818 : set ts=17
3819 :
3820 : " Do the hard work here.
3821 :
3822 :finally
3823 : let &ts = s:saved_ts
3824 : unlet s:saved_ts
3825 :endtry
3826
3827This method should be used locally whenever a function or part of a script
3828changes global settings which need to be restored on failure or normal exit of
3829that function or script part.
3830
3831 *break-finally*
3832Cleanup code works also when the try block or a catch clause is left by
3833a ":continue", ":break", ":return", or ":finish".
3834 Example: >
3835
3836 :let first = 1
3837 :while 1
3838 : try
3839 : if first
3840 : echo "first"
3841 : let first = 0
3842 : continue
3843 : else
3844 : throw "second"
3845 : endif
3846 : catch /.*/
3847 : echo v:exception
3848 : break
3849 : finally
3850 : echo "cleanup"
3851 : endtry
3852 : echo "still in while"
3853 :endwhile
3854 :echo "end"
3855
3856This displays "first", "cleanup", "second", "cleanup", and "end". >
3857
3858 :function! Foo()
3859 : try
3860 : return 4711
3861 : finally
3862 : echo "cleanup\n"
3863 : endtry
3864 : echo "Foo still active"
3865 :endfunction
3866 :
3867 :echo Foo() "returned by Foo"
3868
3869This displays "cleanup" and "4711 returned by Foo". You don't need to add an
3870extra ":return" in the finally clause. (Above all, this would override the
3871return value.)
3872
3873 *except-from-finally*
3874Using either of ":continue", ":break", ":return", ":finish", or ":throw" in
3875a finally clause is possible, but not recommended since it abandons the
3876cleanup actions for the try conditional. But, of course, interrupt and error
3877exceptions might get raised from a finally clause.
3878 Example where an error in the finally clause stops an interrupt from
3879working correctly: >
3880
3881 :try
3882 : try
3883 : echo "Press CTRL-C for interrupt"
3884 : while 1
3885 : endwhile
3886 : finally
3887 : unlet novar
3888 : endtry
3889 :catch /novar/
3890 :endtry
3891 :echo "Script still running"
3892 :sleep 1
3893
3894If you need to put commands that could fail into a finally clause, you should
3895think about catching or ignoring the errors in these commands, see
3896|catch-errors| and |ignore-errors|.
3897
3898
3899CATCHING ERRORS *catch-errors*
3900
3901If you want to catch specific errors, you just have to put the code to be
3902watched in a try block and add a catch clause for the error message. The
3903presence of the try conditional causes all errors to be converted to an
3904exception. No message is displayed and |v:errmsg| is not set then. To find
3905the right pattern for the ":catch" command, you have to know how the format of
3906the error exception is.
3907 Error exceptions have the following format: >
3908
3909 Vim({cmdname}):{errmsg}
3910or >
3911 Vim:{errmsg}
3912
3913{cmdname} is the name of the command that failed; the second form is used when
3914the command name is not known. {errmsg} is the error message usually produced
3915when the error occurs outside try conditionals. It always begins with
3916a capital "E", followed by a two or three-digit error number, a colon, and
3917a space.
3918
3919Examples:
3920
3921The command >
3922 :unlet novar
3923normally produces the error message >
3924 E108: No such variable: "novar"
3925which is converted inside try conditionals to an exception >
3926 Vim(unlet):E108: No such variable: "novar"
3927
3928The command >
3929 :dwim
3930normally produces the error message >
3931 E492: Not an editor command: dwim
3932which is converted inside try conditionals to an exception >
3933 Vim:E492: Not an editor command: dwim
3934
3935You can catch all ":unlet" errors by a >
3936 :catch /^Vim(unlet):/
3937or all errors for misspelled command names by a >
3938 :catch /^Vim:E492:/
3939
3940Some error messages may be produced by different commands: >
3941 :function nofunc
3942and >
3943 :delfunction nofunc
3944both produce the error message >
3945 E128: Function name must start with a capital: nofunc
3946which is converted inside try conditionals to an exception >
3947 Vim(function):E128: Function name must start with a capital: nofunc
3948or >
3949 Vim(delfunction):E128: Function name must start with a capital: nofunc
3950respectively. You can catch the error by its number independently on the
3951command that caused it if you use the following pattern: >
3952 :catch /^Vim(\a\+):E128:/
3953
3954Some commands like >
3955 :let x = novar
3956produce multiple error messages, here: >
3957 E121: Undefined variable: novar
3958 E15: Invalid expression: novar
3959Only the first is used for the exception value, since it is the most specific
3960one (see |except-several-errors|). So you can catch it by >
3961 :catch /^Vim(\a\+):E121:/
3962
3963You can catch all errors related to the name "nofunc" by >
3964 :catch /\<nofunc\>/
3965
3966You can catch all Vim errors in the ":write" and ":read" commands by >
3967 :catch /^Vim(\(write\|read\)):E\d\+:/
3968
3969You can catch all Vim errors by the pattern >
3970 :catch /^Vim\((\a\+)\)\=:E\d\+:/
3971<
3972 *catch-text*
3973NOTE: You should never catch the error message text itself: >
3974 :catch /No such variable/
3975only works in the english locale, but not when the user has selected
3976a different language by the |:language| command. It is however helpful to
3977cite the message text in a comment: >
3978 :catch /^Vim(\a\+):E108:/ " No such variable
3979
3980
3981IGNORING ERRORS *ignore-errors*
3982
3983You can ignore errors in a specific Vim command by catching them locally: >
3984
3985 :try
3986 : write
3987 :catch
3988 :endtry
3989
3990But you are strongly recommended NOT to use this simple form, since it could
3991catch more than you want. With the ":write" command, some autocommands could
3992be executed and cause errors not related to writing, for instance: >
3993
3994 :au BufWritePre * unlet novar
3995
3996There could even be such errors you are not responsible for as a script
3997writer: a user of your script might have defined such autocommands. You would
3998then hide the error from the user.
3999 It is much better to use >
4000
4001 :try
4002 : write
4003 :catch /^Vim(write):/
4004 :endtry
4005
4006which only catches real write errors. So catch only what you'd like to ignore
4007intentionally.
4008
4009For a single command that does not cause execution of autocommands, you could
4010even suppress the conversion of errors to exceptions by the ":silent!"
4011command: >
4012 :silent! nunmap k
4013This works also when a try conditional is active.
4014
4015
4016CATCHING INTERRUPTS *catch-interrupt*
4017
4018When there are active try conditionals, an interrupt (CTRL-C) is converted to
4019the exception "Vim:Interrupt". You can catch it like every exception. The
4020script is not terminated, then.
4021 Example: >
4022
4023 :function! TASK1()
4024 : sleep 10
4025 :endfunction
4026
4027 :function! TASK2()
4028 : sleep 20
4029 :endfunction
4030
4031 :while 1
4032 : let command = input("Type a command: ")
4033 : try
4034 : if command == ""
4035 : continue
4036 : elseif command == "END"
4037 : break
4038 : elseif command == "TASK1"
4039 : call TASK1()
4040 : elseif command == "TASK2"
4041 : call TASK2()
4042 : else
4043 : echo "\nIllegal command:" command
4044 : continue
4045 : endif
4046 : catch /^Vim:Interrupt$/
4047 : echo "\nCommand interrupted"
4048 : " Caught the interrupt. Continue with next prompt.
4049 : endtry
4050 :endwhile
4051
4052You can interrupt a task here by pressing CTRL-C; the script then asks for
4053a new command. If you press CTRL-C at the prompt, the script is terminated.
4054
4055For testing what happens when CTRL-C would be pressed on a specific line in
4056your script, use the debug mode and execute the |>quit| or |>interrupt|
4057command on that line. See |debug-scripts|.
4058
4059
4060CATCHING ALL *catch-all*
4061
4062The commands >
4063
4064 :catch /.*/
4065 :catch //
4066 :catch
4067
4068catch everything, error exceptions, interrupt exceptions and exceptions
4069explicitly thrown by the |:throw| command. This is useful at the top level of
4070a script in order to catch unexpected things.
4071 Example: >
4072
4073 :try
4074 :
4075 : " do the hard work here
4076 :
4077 :catch /MyException/
4078 :
4079 : " handle known problem
4080 :
4081 :catch /^Vim:Interrupt$/
4082 : echo "Script interrupted"
4083 :catch /.*/
4084 : echo "Internal error (" . v:exception . ")"
4085 : echo " - occurred at " . v:throwpoint
4086 :endtry
4087 :" end of script
4088
4089Note: Catching all might catch more things than you want. Thus, you are
4090strongly encouraged to catch only for problems that you can really handle by
4091specifying a pattern argument to the ":catch".
4092 Example: Catching all could make it nearly impossible to interrupt a script
4093by pressing CTRL-C: >
4094
4095 :while 1
4096 : try
4097 : sleep 1
4098 : catch
4099 : endtry
4100 :endwhile
4101
4102
4103EXCEPTIONS AND AUTOCOMMANDS *except-autocmd*
4104
4105Exceptions may be used during execution of autocommands. Example: >
4106
4107 :autocmd User x try
4108 :autocmd User x throw "Oops!"
4109 :autocmd User x catch
4110 :autocmd User x echo v:exception
4111 :autocmd User x endtry
4112 :autocmd User x throw "Arrgh!"
4113 :autocmd User x echo "Should not be displayed"
4114 :
4115 :try
4116 : doautocmd User x
4117 :catch
4118 : echo v:exception
4119 :endtry
4120
4121This displays "Oops!" and "Arrgh!".
4122
4123 *except-autocmd-Pre*
4124For some commands, autocommands get executed before the main action of the
4125command takes place. If an exception is thrown and not caught in the sequence
4126of autocommands, the sequence and the command that caused its execution are
4127abandoned and the exception is propagated to the caller of the command.
4128 Example: >
4129
4130 :autocmd BufWritePre * throw "FAIL"
4131 :autocmd BufWritePre * echo "Should not be displayed"
4132 :
4133 :try
4134 : write
4135 :catch
4136 : echo "Caught:" v:exception "from" v:throwpoint
4137 :endtry
4138
4139Here, the ":write" command does not write the file currently being edited (as
4140you can see by checking 'modified'), since the exception from the BufWritePre
4141autocommand abandons the ":write". The exception is then caught and the
4142script displays: >
4143
4144 Caught: FAIL from BufWrite Auto commands for "*"
4145<
4146 *except-autocmd-Post*
4147For some commands, autocommands get executed after the main action of the
4148command has taken place. If this main action fails and the command is inside
4149an active try conditional, the autocommands are skipped and an error exception
4150is thrown that can be caught by the caller of the command.
4151 Example: >
4152
4153 :autocmd BufWritePost * echo "File successfully written!"
4154 :
4155 :try
4156 : write /i/m/p/o/s/s/i/b/l/e
4157 :catch
4158 : echo v:exception
4159 :endtry
4160
4161This just displays: >
4162
4163 Vim(write):E212: Can't open file for writing (/i/m/p/o/s/s/i/b/l/e)
4164
4165If you really need to execute the autocommands even when the main action
4166fails, trigger the event from the catch clause.
4167 Example: >
4168
4169 :autocmd BufWritePre * set noreadonly
4170 :autocmd BufWritePost * set readonly
4171 :
4172 :try
4173 : write /i/m/p/o/s/s/i/b/l/e
4174 :catch
4175 : doautocmd BufWritePost /i/m/p/o/s/s/i/b/l/e
4176 :endtry
4177<
4178You can also use ":silent!": >
4179
4180 :let x = "ok"
4181 :let v:errmsg = ""
4182 :autocmd BufWritePost * if v:errmsg != ""
4183 :autocmd BufWritePost * let x = "after fail"
4184 :autocmd BufWritePost * endif
4185 :try
4186 : silent! write /i/m/p/o/s/s/i/b/l/e
4187 :catch
4188 :endtry
4189 :echo x
4190
4191This displays "after fail".
4192
4193If the main action of the command does not fail, exceptions from the
4194autocommands will be catchable by the caller of the command: >
4195
4196 :autocmd BufWritePost * throw ":-("
4197 :autocmd BufWritePost * echo "Should not be displayed"
4198 :
4199 :try
4200 : write
4201 :catch
4202 : echo v:exception
4203 :endtry
4204<
4205 *except-autocmd-Cmd*
4206For some commands, the normal action can be replaced by a sequence of
4207autocommands. Exceptions from that sequence will be catchable by the caller
4208of the command.
4209 Example: For the ":write" command, the caller cannot know whether the file
4210had actually been written when the exception occurred. You need to tell it in
4211some way. >
4212
4213 :if !exists("cnt")
4214 : let cnt = 0
4215 :
4216 : autocmd BufWriteCmd * if &modified
4217 : autocmd BufWriteCmd * let cnt = cnt + 1
4218 : autocmd BufWriteCmd * if cnt % 3 == 2
4219 : autocmd BufWriteCmd * throw "BufWriteCmdError"
4220 : autocmd BufWriteCmd * endif
4221 : autocmd BufWriteCmd * write | set nomodified
4222 : autocmd BufWriteCmd * if cnt % 3 == 0
4223 : autocmd BufWriteCmd * throw "BufWriteCmdError"
4224 : autocmd BufWriteCmd * endif
4225 : autocmd BufWriteCmd * echo "File successfully written!"
4226 : autocmd BufWriteCmd * endif
4227 :endif
4228 :
4229 :try
4230 : write
4231 :catch /^BufWriteCmdError$/
4232 : if &modified
4233 : echo "Error on writing (file contents not changed)"
4234 : else
4235 : echo "Error after writing"
4236 : endif
4237 :catch /^Vim(write):/
4238 : echo "Error on writing"
4239 :endtry
4240
4241When this script is sourced several times after making changes, it displays
4242first >
4243 File successfully written!
4244then >
4245 Error on writing (file contents not changed)
4246then >
4247 Error after writing
4248etc.
4249
4250 *except-autocmd-ill*
4251You cannot spread a try conditional over autocommands for different events.
4252The following code is ill-formed: >
4253
4254 :autocmd BufWritePre * try
4255 :
4256 :autocmd BufWritePost * catch
4257 :autocmd BufWritePost * echo v:exception
4258 :autocmd BufWritePost * endtry
4259 :
4260 :write
4261
4262
4263EXCEPTION HIERARCHIES AND PARAMETERIZED EXCEPTIONS *except-hier-param*
4264
4265Some programming languages allow to use hierarchies of exception classes or to
4266pass additional information with the object of an exception class. You can do
4267similar things in Vim.
4268 In order to throw an exception from a hierarchy, just throw the complete
4269class name with the components separated by a colon, for instance throw the
4270string "EXCEPT:MATHERR:OVERFLOW" for an overflow in a mathematical library.
4271 When you want to pass additional information with your exception class, add
4272it in parentheses, for instance throw the string "EXCEPT:IO:WRITEERR(myfile)"
4273for an error when writing "myfile".
4274 With the appropriate patterns in the ":catch" command, you can catch for
4275base classes or derived classes of your hierarchy. Additional information in
4276parentheses can be cut out from |v:exception| with the ":substitute" command.
4277 Example: >
4278
4279 :function! CheckRange(a, func)
4280 : if a:a < 0
4281 : throw "EXCEPT:MATHERR:RANGE(" . a:func . ")"
4282 : endif
4283 :endfunction
4284 :
4285 :function! Add(a, b)
4286 : call CheckRange(a:a, "Add")
4287 : call CheckRange(a:b, "Add")
4288 : let c = a:a + a:b
4289 : if c < 0
4290 : throw "EXCEPT:MATHERR:OVERFLOW"
4291 : endif
4292 : return c
4293 :endfunction
4294 :
4295 :function! Div(a, b)
4296 : call CheckRange(a:a, "Div")
4297 : call CheckRange(a:b, "Div")
4298 : if (a:b == 0)
4299 : throw "EXCEPT:MATHERR:ZERODIV"
4300 : endif
4301 : return a:a / a:b
4302 :endfunction
4303 :
4304 :function! Write(file)
4305 : try
4306 : execute "write" a:file
4307 : catch /^Vim(write):/
4308 : throw "EXCEPT:IO(" . getcwd() . ", " . a:file . "):WRITEERR"
4309 : endtry
4310 :endfunction
4311 :
4312 :try
4313 :
4314 : " something with arithmetics and I/O
4315 :
4316 :catch /^EXCEPT:MATHERR:RANGE/
4317 : let function = substitute(v:exception, '.*(\(\a\+\)).*', '\1', "")
4318 : echo "Range error in" function
4319 :
4320 :catch /^EXCEPT:MATHERR/ " catches OVERFLOW and ZERODIV
4321 : echo "Math error"
4322 :
4323 :catch /^EXCEPT:IO/
4324 : let dir = substitute(v:exception, '.*(\(.\+\),\s*.\+).*', '\1', "")
4325 : let file = substitute(v:exception, '.*(.\+,\s*\(.\+\)).*', '\1', "")
4326 : if file !~ '^/'
4327 : let file = dir . "/" . file
4328 : endif
4329 : echo 'I/O error for "' . file . '"'
4330 :
4331 :catch /^EXCEPT/
4332 : echo "Unspecified error"
4333 :
4334 :endtry
4335
4336The exceptions raised by Vim itself (on error or when pressing CTRL-C) use
4337a flat hierarchy: they are all in the "Vim" class. You cannot throw yourself
4338exceptions with the "Vim" prefix; they are reserved for Vim.
4339 Vim error exceptions are parameterized with the name of the command that
4340failed, if known. See |catch-errors|.
4341
4342
4343PECULIARITIES
4344 *except-compat*
4345The exception handling concept requires that the command sequence causing the
4346exception is aborted immediately and control is transferred to finally clauses
4347and/or a catch clause.
4348
4349In the Vim script language there are cases where scripts and functions
4350continue after an error: in functions without the "abort" flag or in a command
4351after ":silent!", control flow goes to the following line, and outside
4352functions, control flow goes to the line following the outermost ":endwhile"
4353or ":endif". On the other hand, errors should be catchable as exceptions
4354(thus, requiring the immediate abortion).
4355
4356This problem has been solved by converting errors to exceptions and using
4357immediate abortion (if not suppressed by ":silent!") only when a try
4358conditional is active. This is no restriction since an (error) exception can
4359be caught only from an active try conditional. If you want an immediate
4360termination without catching the error, just use a try conditional without
4361catch clause. (You can cause cleanup code being executed before termination
4362by specifying a finally clause.)
4363
4364When no try conditional is active, the usual abortion and continuation
4365behavior is used instead of immediate abortion. This ensures compatibility of
4366scripts written for Vim 6.1 and earlier.
4367
4368However, when sourcing an existing script that does not use exception handling
4369commands (or when calling one of its functions) from inside an active try
4370conditional of a new script, you might change the control flow of the existing
4371script on error. You get the immediate abortion on error and can catch the
4372error in the new script. If however the sourced script suppresses error
4373messages by using the ":silent!" command (checking for errors by testing
4374|v:errmsg| if appropriate), its execution path is not changed. The error is
4375not converted to an exception. (See |:silent|.) So the only remaining cause
4376where this happens is for scripts that don't care about errors and produce
4377error messages. You probably won't want to use such code from your new
4378scripts.
4379
4380 *except-syntax-err*
4381Syntax errors in the exception handling commands are never caught by any of
4382the ":catch" commands of the try conditional they belong to. Its finally
4383clauses, however, is executed.
4384 Example: >
4385
4386 :try
4387 : try
4388 : throw 4711
4389 : catch /\(/
4390 : echo "in catch with syntax error"
4391 : catch
4392 : echo "inner catch-all"
4393 : finally
4394 : echo "inner finally"
4395 : endtry
4396 :catch
4397 : echo 'outer catch-all caught "' . v:exception . '"'
4398 : finally
4399 : echo "outer finally"
4400 :endtry
4401
4402This displays: >
4403 inner finally
4404 outer catch-all caught "Vim(catch):E54: Unmatched \("
4405 outer finally
4406The original exception is discarded and an error exception is raised, instead.
4407
4408 *except-single-line*
4409The ":try", ":catch", ":finally", and ":endtry" commands can be put on
4410a single line, but then syntax errors may make it difficult to recognize the
4411"catch" line, thus you better avoid this.
4412 Example: >
4413 :try | unlet! foo # | catch | endtry
4414raises an error exception for the trailing characters after the ":unlet!"
4415argument, but does not see the ":catch" and ":endtry" commands, so that the
4416error exception is discarded and the "E488: Trailing characters" message gets
4417displayed.
4418
4419 *except-several-errors*
4420When several errors appear in a single command, the first error message is
4421usually the most specific one and therefor converted to the error exception.
4422 Example: >
4423 echo novar
4424causes >
4425 E121: Undefined variable: novar
4426 E15: Invalid expression: novar
4427The value of the error exception inside try conditionals is: >
4428 Vim(echo):E121: Undefined variable: novar
4429< *except-syntax-error*
4430But when a syntax error is detected after a normal error in the same command,
4431the syntax error is used for the exception being thrown.
4432 Example: >
4433 unlet novar #
4434causes >
4435 E108: No such variable: "novar"
4436 E488: Trailing characters
4437The value of the error exception inside try conditionals is: >
4438 Vim(unlet):E488: Trailing characters
4439This is done because the syntax error might change the execution path in a way
4440not intended by the user. Example: >
4441 try
4442 try | unlet novar # | catch | echo v:exception | endtry
4443 catch /.*/
4444 echo "outer catch:" v:exception
4445 endtry
4446This displays "outer catch: Vim(unlet):E488: Trailing characters", and then
4447a "E600: Missing :endtry" error message is given, see |except-single-line|.
4448
4449==============================================================================
44509. Examples *eval-examples*
4451
4452Printing in Hex ~
4453>
4454 :" The function Nr2Hex() returns the Hex string of a number.
4455 :func Nr2Hex(nr)
4456 : let n = a:nr
4457 : let r = ""
4458 : while n
4459 : let r = '0123456789ABCDEF'[n % 16] . r
4460 : let n = n / 16
4461 : endwhile
4462 : return r
4463 :endfunc
4464
4465 :" The function String2Hex() converts each character in a string to a two
4466 :" character Hex string.
4467 :func String2Hex(str)
4468 : let out = ''
4469 : let ix = 0
4470 : while ix < strlen(a:str)
4471 : let out = out . Nr2Hex(char2nr(a:str[ix]))
4472 : let ix = ix + 1
4473 : endwhile
4474 : return out
4475 :endfunc
4476
4477Example of its use: >
4478 :echo Nr2Hex(32)
4479result: "20" >
4480 :echo String2Hex("32")
4481result: "3332"
4482
4483
4484Sorting lines (by Robert Webb) ~
4485
4486Here is a Vim script to sort lines. Highlight the lines in Vim and type
4487":Sort". This doesn't call any external programs so it'll work on any
4488platform. The function Sort() actually takes the name of a comparison
4489function as its argument, like qsort() does in C. So you could supply it
4490with different comparison functions in order to sort according to date etc.
4491>
4492 :" Function for use with Sort(), to compare two strings.
4493 :func! Strcmp(str1, str2)
4494 : if (a:str1 < a:str2)
4495 : return -1
4496 : elseif (a:str1 > a:str2)
4497 : return 1
4498 : else
4499 : return 0
4500 : endif
4501 :endfunction
4502
4503 :" Sort lines. SortR() is called recursively.
4504 :func! SortR(start, end, cmp)
4505 : if (a:start >= a:end)
4506 : return
4507 : endif
4508 : let partition = a:start - 1
4509 : let middle = partition
4510 : let partStr = getline((a:start + a:end) / 2)
4511 : let i = a:start
4512 : while (i <= a:end)
4513 : let str = getline(i)
4514 : exec "let result = " . a:cmp . "(str, partStr)"
4515 : if (result <= 0)
4516 : " Need to put it before the partition. Swap lines i and partition.
4517 : let partition = partition + 1
4518 : if (result == 0)
4519 : let middle = partition
4520 : endif
4521 : if (i != partition)
4522 : let str2 = getline(partition)
4523 : call setline(i, str2)
4524 : call setline(partition, str)
4525 : endif
4526 : endif
4527 : let i = i + 1
4528 : endwhile
4529
4530 : " Now we have a pointer to the "middle" element, as far as partitioning
4531 : " goes, which could be anywhere before the partition. Make sure it is at
4532 : " the end of the partition.
4533 : if (middle != partition)
4534 : let str = getline(middle)
4535 : let str2 = getline(partition)
4536 : call setline(middle, str2)
4537 : call setline(partition, str)
4538 : endif
4539 : call SortR(a:start, partition - 1, a:cmp)
4540 : call SortR(partition + 1, a:end, a:cmp)
4541 :endfunc
4542
4543 :" To Sort a range of lines, pass the range to Sort() along with the name of a
4544 :" function that will compare two lines.
4545 :func! Sort(cmp) range
4546 : call SortR(a:firstline, a:lastline, a:cmp)
4547 :endfunc
4548
4549 :" :Sort takes a range of lines and sorts them.
4550 :command! -nargs=0 -range Sort <line1>,<line2>call Sort("Strcmp")
4551<
4552 *sscanf*
4553There is no sscanf() function in Vim. If you need to extract parts from a
4554line, you can use matchstr() and substitute() to do it. This example shows
4555how to get the file name, line number and column number out of a line like
4556"foobar.txt, 123, 45". >
4557 :" Set up the match bit
4558 :let mx='\(\f\+\),\s*\(\d\+\),\s*\(\d\+\)'
4559 :"get the part matching the whole expression
4560 :let l = matchstr(line, mx)
4561 :"get each item out of the match
4562 :let file = substitute(l, mx, '\1', '')
4563 :let lnum = substitute(l, mx, '\2', '')
4564 :let col = substitute(l, mx, '\3', '')
4565
4566The input is in the variable "line", the results in the variables "file",
4567"lnum" and "col". (idea from Michael Geddes)
4568
4569==============================================================================
457010. No +eval feature *no-eval-feature*
4571
4572When the |+eval| feature was disabled at compile time, none of the expression
4573evaluation commands are available. To prevent this from causing Vim scripts
4574to generate all kinds of errors, the ":if" and ":endif" commands are still
4575recognized, though the argument of the ":if" and everything between the ":if"
4576and the matching ":endif" is ignored. Nesting of ":if" blocks is allowed, but
4577only if the commands are at the start of the line. The ":else" command is not
4578recognized.
4579
4580Example of how to avoid executing commands when the |+eval| feature is
4581missing: >
4582
4583 :if 1
4584 : echo "Expression evaluation is compiled in"
4585 :else
4586 : echo "You will _never_ see this message"
4587 :endif
4588
4589==============================================================================
459011. The sandbox *eval-sandbox* *sandbox* *E48*
4591
4592The 'foldexpr', 'includeexpr', 'indentexpr', 'statusline' and 'foldtext'
4593options are evaluated in a sandbox. This means that you are protected from
4594these expressions having nasty side effects. This gives some safety for when
4595these options are set from a modeline. It is also used when the command from
4596a tags file is executed.
4597This is not guaranteed 100% secure, but it should block most attacks.
4598
4599These items are not allowed in the sandbox:
4600 - changing the buffer text
4601 - defining or changing mapping, autocommands, functions, user commands
4602 - setting certain options (see |option-summary|)
4603 - executing a shell command
4604 - reading or writing a file
4605 - jumping to another buffer or editing a file
4606
4607 vim:tw=78:ts=8:ft=help:norl: