*eval.txt* For Vim version 5.3. Last modification: 1998 Aug 22 VIM REFERENCE MANUAL by Bram Moolenaar Expression evaluation *expression* *expr* Note: Expression evaluation can be disabled at compile time. If this has been done, the features in this document are not available. See |+eval|. 1. Variables |variables| 2. Expression syntax |expression-syntax| 3. Internal variable |internal-variables| 4. Builtin Functions |functions| 5. Defining functions |user-functions| 6. Commands |expression-commands| {Vi does not have any of these commands} ============================================================================== 1. Variables *variables* There are two types of variables: Number a 32 bit signed number String a NUL terminated string of 8-bit unsigned characters. These are converted automatically, depending on how they are used. Conversion from a Number to a String is by making the ASCII representation of the Number. Examples: > Number 123 --> String "123" > Number 0 --> String "0" > Number -1 --> String "-1" Conversion from a String to a Number is done by converting the first digits to a number. Hexadecimal "0xf9" and Octal "017" numbers are recognized. If the String doesn't start with digits, the result is zero. Examples: > String "456" --> Number 456 > String "6bar" --> Number 6 > String "foo" --> Number 0 > String "0xf1" --> Number 241 > String "0100" --> Number 64 For boolean operators Numbers are used. Zero is FALSE, non-zero is TRUE. Note that in the command :if "foo" "foo" is converted to 0, which means FALSE. To test for a non-empty string, use strlen(): :if strlen("foo") ============================================================================== 2. Expression syntax *expression-syntax* Expression syntax summary, from least to most significant: |expr1| expr2 || expr2 .. logical OR |expr2| expr3 && expr3 .. logical AND |expr3| expr4 == expr4 equal expr4 != expr4 not equal expr4 > expr4 greater than expr4 >= expr4 greater than or equal expr4 < expr4 smaller than expr4 <= expr4 smaller than or equal expr4 =~ expr4 regexp matches expr4 !~ expr4 regexp doesn't match |expr4| expr5 + expr5 .. number addition expr5 - expr5 .. number subtraction expr5 . expr5 .. string concatenation |expr5| expr6 * expr6 .. number multiplication expr6 / expr6 .. number division expr6 % expr6 .. number modulo |expr6| ! expr6 logical NOT - expr6 unary minus |expr7| expr8[expr1] index in String |expr8| number number constant "string" string constant 'string' literal string constant &option option value (expr1) nested expression variable internal variable $VAR environment variable @r contents of register 'r' function(expr1, ...) function call ".." indicates that the operations in this level can be concatenated. Example: > &nu || &list && &shell == "csh" All expressions within one level are parsed from left to right. expr1 and expr2 *expr1* *expr2* --------------- *expr-barbar* *expr-&&* The "||" and "&&" operators take one argument on each side. The arguments are (converted to) Numbers. The result is: input output ~ n1 n2 n1 || n2 n1 && n2 ~ zero zero zero zero zero non-zero non-zero zero non-zero zero non-zero zero non-zero non-zero non-zero non-zero The operators can be concatenated, for example: > &nu || &list && &shell == "csh" Note that "&&" takes precedence over "||", so this has the meaning of: > &nu || (&list && &shell == "csh") All arguments are computed, there is no skipping if the value of an argument doesn't matter, because the result is already known. This is different from C, although it only matters for errors (unknown variables), since there are no side effects from an expression. expr3 *expr3* ----- expr4 == expr4 equal *expr-==* expr4 != expr4 not equal *expr-!=* expr4 > expr4 greater than *expr->* expr4 >= expr4 greater than or equal *expr->=* expr4 < expr4 smaller than *expr-<* expr4 <= expr4 smaller than or equal *expr-<=* expr4 =~ expr4 regexp matches *expr-=~* expr4 !~ expr4 regexp doesn't match *expr-!~* When comparing a String with a Number, the String is converted to a Number, and the comparison is done on Numbers. When comparing two Strings, this is done with strcmp(). This results in the mathematical difference, not necessarily the alphabetical difference in the local language. The "=~" and "!~" operators match the lefthand argument with the righthand argument, which is used as a pattern. See |pattern| for what a pattern is. This matching is always done like 'magic' was set, no matter what the actual value of 'magic' is. This makes scripts portable. The value of 'ignorecase' does matter though. To avoid backslashes in the regexp pattern to be doubled, use a single-quote string, see |literal-string|. expr4 and expr5 *expr4* *expr5* --------------- expr5 + expr5 .. number addition *expr-+* expr5 - expr5 .. number subtraction *expr--* expr5 . expr5 .. string concatenation *expr-.* expr6 * expr6 .. number multiplication *expr-star* expr6 / expr6 .. number division *expr-/* expr6 % expr6 .. number modulo *expr-%* For all, except ".", Strings are converted to Numbers. Note the difference between "+" and ".": "123" + "456" = 579 "123" . "456" = "123456" When the righthand side of '/' is zero, the result is 0xfffffff. When the righthand side of '%' is zero, the result is 0. expr6 *expr6* ----- ! expr6 logical NOT *expr-!* - expr6 unary minus *expr-unary--* For '!' non-zero becomes zero, zero becomes one. For '-' the sign of the number is changed. A String will be converted to a Number first. These two can be repeated and mixed. Examples: !-1 == 0 !!8 == 1 --9 == 9 expr7 *expr7* ----- expr8[expr1] index in String *expr-[]* This results in a String that contains the expr1'th single character from expr8. expr8 is used as a String, expr1 as a Number. Note that index zero gives the first character. This is like it works in C. Careful: column numbers start with one! Example, to get the character under the cursor: > c = getline(line("."))[col(".") - 1] If the length of the String is less than the index, the result is an empty String. *expr8* number ------ number number constant *expr-number* Decimal, Hexadecimal (starting with 0x or 0X), or Octal (starting with 0). string *expr-string* ------ "string" string constant *expr-quote* Note that double quotes are used. A string constant accepts these special characters: \... three-digit octal number (e.g., "\316") \.. two-digit octal number (must be followed by non-digit) \. one-digit octal number (must be followed by non-digit) \x.. two-character hex number (e.g., "\x1f") \x. one-character hex number (must be followed by non-hex) \X.. same as \x.. \X. same as \x. \b backspace \e escape \f formfeed \n newline \r return \t tab \\ backslash \" double quote \ Special key named "xxx". e.g. "\" for CTRL-W. Note that "\000" and "\x00" force the end of the string. literal-string *literal-string* --------------- 'string' literal string constant *expr-'* Note that single quotes are used. This string is taken literally. No backslashes are removed or have a special meaning. A literal-string cannot contain a single quote. Use a normal string for that. option *expr-option* ------ &option option value Any option name can be used here. See |options|. register *expr-register* -------- @r contents of register 'r' The result is the contents of the named register, as a single string. Newlines are inserted where required. To get the contents of the unnamed register use @@. The '=' register can not be used here. See |registers| for an explanation of the available registers. nesting *expr-nesting* ------- (expr1) nested expression environment variable *expr-env* -------------------- $VAR environment variable The String value of any environment variable. When it is not defined, the result is an empty string. internal variable *expr-variable* ----------------- variable internal variable See below |internal-variables|. function call *expr-function* ------------- function(expr1, ...) function call See below |functions|. ============================================================================== 3. Internal variable *internal-variables* An internal variable name can be made up of letters, digits and '_'. But it cannot start with a digit. An internal variable is created with the ":let" command |:let|. An internal variable is destroyed with the ":unlet" command |:unlet|. Using a name that isn't an internal variable, or an internal variable that has been destroyed, results in an error. A variable name that is preceded with "b:" is local to the current buffer. A variable name that is preceded with "w:" is local to the current window. Inside functions global variables are accessed with "g:". Predefined variables: *count-variable* count The count given for the last Normal mode command. Can be used to get the count before a mapping. Example: > :map _x :echo "the count is " . count Note: The is required to remove the line range that you get when typing ':' after a count. read-only. *errmsg-variable* errmsg Last given error message. It's allowed to set this variable. Example: > :let errmsg = "" > :next > :if (errmsg != "") > : ... *shell_error-variable* shell_error Result of the last shell command. When non-zero, the last shell command had an error. When zero, there was no problem. This only works when the shell returns the error code to Vim. The value -1 is often used when the command could not be executed. Example: > :!mv foo bar > :if shell_error > : echo 'could not rename "foo" to "bar"!' > :endif *this_session-variable* this_session Full filename of the last loaded or saved session file. See |:mksession|. *version-variable* version Version number of Vim: Major version number times 100 plus minor version number. Version 5.0 is 500. Version 5.1 (5.01) is 501. Read-only. ============================================================================== 4. Builtin Functions *functions* USAGE RESULT DESCRIPTION ~ argc() Number number of files in the argument list argv({nr}) String {nr} entry of the argument list browse({save}, {title}, {initdir}, {default}) String put up a file requester bufexists({expr}) Number TRUE if a buffer {exp} exists bufname({expr}) String Name of the buffer {expr} bufnr({expr}) Number Number of the buffer {expr} char2nr({expr}) Number ASCII value of first char in {expr} col({expr}) Number column nr of cursor or mark confirm({msg}, {choices}, {default}) Number number of choice picked by user delete({fname}) Number delete file {fname} escape({string}, {chars}) String escape {chars} in {string} with '\' exists({var}) Number TRUE if {var} exists expand({expr}) String expand file wildcards in {expr} filereadable({file}) Number TRUE if {file} is a readable file fnamemodify({fname}, {mods}) String modify file name getcwd() String the current working directory getline({lnum}) String line {lnum} from current buffer has({feature}) Number TRUE if feature {feature} supported hlexists({name}) Number TRUE if highlight group {name} exists hlID({name}) Number syntax ID of highlight group {name} hostname() String name of the machine vim is running on input({prompt}) String get input from the user isdirectory({directory}) Number TRUE if {directory} is a directory line({expr}) Number line nr of cursor, last line or mark match({expr}, {pat}) Number position where {pat} matches in {expr} matchend({expr}, {pat}) Number position where {pat} ends in {expr} matchstr({expr}, {pat}) String match of {pat} in {expr} nr2char({expr}) String single char with ASCII value {expr} setline({lnum}, {line}) Number Set line {lnum} to {line} strftime({expr}) String current time in specified format strlen({expr}) Number length of the String {expr} strpart({src}, {start}, {len}) String {len} characters of {src} at {start} synID({line}, {col}, {trans}) Number syntax ID at {line} and {col} synIDattr({synID}, {what}) String attribute {what} of syntax ID {synID} synIDtrans({synID}) Number translated syntax ID of {synID} substitute({expr}, {pat}, {sub}, {flags}) String all {pat} in {expr} replaced with {sub} tempname() String name for a temporary file virtcol({expr}) Number screen column of cursor or mark winbufnr({nr}) Number buffer number of window {nr} winheight({nr}) Number height of window {nr} winnr() Number number of current window *argc()* argc() The result is the number of files in the argument list. See |arglist|. *argv()* argv({nr}) The result is the {nr}th file in the argument list. See |arglist|. "argv(0)" is the first one. Example: > let i = 0 > while i < argc() > let f = substitute(argv(i), '\([. ]\)', '\\&', 'g') > exe 'amenu Arg.' . f . ' :e ' . f . '' > let i = i + 1 > endwhile *browse()* browse({save}, {title}, {initdir}, {default}) Put up a file requester. This only works when "has("browse")" returns non-zero (only in some GUI versions). The input fields are: {save} when non-zero, select file to write {title} title for the requester {initdir} directory to start browsing in {default} default file name When the "Cancel" button is hit, something went wrong, or browsing is not possible, an empty string is returned. *bufexists()* bufexists({var}) The result is a Number, which is non-zero if a buffer called {var} exists. If the {var} argument is a string it must match a buffer name exactly. If the {var} argument is a number buffer numbers are used. Use "bufexists(0)" to test for the existence of an alternate file name. *buffer_exists()* Obsolete name: buffer_exists(). *bufname()* bufname({expr}) The result is the name of a buffer, as it is displayed by the ":ls" command. If {expr} is a Number, that buffer number's name is given. Number zero is the alternate buffer for the current window. If {expr} is a String, it is used as a regexp pattern to match with the buffer names. When there is more than one match an empty string is returned. "" or "%" can be used for the current buffer, "#" for the alternate buffer. If the {expr} is a String, but you want to use it as a buffer number, force it to be a Number by adding zero to it: > echo bufname("3" + 0) If the buffer doesn't exist, or doesn't have a name, an empty string is returned. > bufname("#") alternate buffer name > bufname(3) name of buffer 3 > bufname("%") name of current buffer > bufname("file2") name of buffer where "file2" matches. *buffer_name()* Obsolete name: buffer_name(). *bufnr()* bufnr({expr}) The result is the number of a buffer, as it is displayed by the ":ls" command. For the use of {expr}, see bufname() above. If the buffer doesn't exist, -1 is returned. bufnr("$") is the last buffer: > :let last_buffer = bufnr("$") The result is a Number, which is the highest buffer number of existing buffers. Note that not all buffers with a smaller number necessarily exist, because ":bdel" may have removed them. Use bufexists() to test for the existence of a buffer. *buffer_number()* Obsolete name: buffer_number(). *last_buffer_nr()* Obsolete name for bufnr("$"): last_buffer_nr(). *char2nr()* char2nr({expr}) Return ASCII value of the first char in {expr}. Examples: > char2nr(" ") returns 32 > char2nr("ABC") returns 65 *col()* col({expr}) The result is a Number, which is the column of the file position given with {expr}. The accepted positions are: . the cursor position 'x position of mark x (if the mark is not set, 0 is returned) Note that only marks in the current file can be used. Examples: > col(".") column of cursor > col("'t") column of mark t > col("'" . markname) column of mark markname The first column is 1. 0 is returned for an error. *confirm()* confirm({msg}, {choices}[, {default} [, {type}]]) Note: confirm() is only supported when compiled with dialog support, see |+dialog_con|. {msg} is displayed in a |dialog| with {choices} as the alternatives. {default} is the number of the choice that is made if the user hits . If {default} is omitted, 0 is used. {msg} is a String, use '\n' to include a newline. Only on some systems the string is wrapped when it doesn't fit. {choices} is a String, with the individual choices separated by '\n', e.g. > "Yes\nNo\nCancel" By default, the first letter of each choice is used as the shortcut key; in the above example the keys y, n, and c would choose the respective option. To override this, put a '&' before the letter you want to use: > "Save\nSave &All" The optional {type} argument gives the type of dialog. This is only used for the icon of the Win32 GUI. It can be one of these values: "Error", "Question", "Info", "Warning" or "Generic". Only the first character is relevant. If the user aborts the dialog by pressing , CTRL-C, or another valid interrupt key, confirm() returns 0. An example: > :let choice = confirm("What do you want?", "Apples\nOranges\nBananas", 2) > :if choice == 0 > : echo "make up your mind!" > :elseif choice == 3 > : echo "tasteful" > :else > : echo "I prefer bananas myself." > :endif In a GUI dialog, buttons are used. The layout of the buttons depends on the 'confirm' option. If it is "vertical", the buttons are always put vertically. Otherwise, confirm() tries to put the buttons in one horizontal line. If they don't fit, a vertical layout is used. *delete()* delete({fname}) Deletes the file by the name {fname}. The result is a Number, which is 0 if the file was deleted successfully, and non-zero when the deletion failed. *escape()* escape({string}, {chars}) Escape the characters in {chars} that occur in {string} with a backslash. Example: > :echo escape('c:\program files\vim', ' \') results in: > c:\\program\ files\\vim *exists()* exists({expr}) The result is a Number, which is 1 if {var} is defined, zero otherwise. The {expr} argument is a string, which contains one of these: &option-name Vim option $ENVNAME environment variable (could also be done by comparing with an empty string) varname internal variable (see |internal-variables|). Examples: > exists("&shortname") > exists("$HOSTNAME") > exists("bufcount") Note that the argument must be a string, not the name of the variable itself! This doesn't check for existence of the "bufcount" variable, but gets the contents of "bufcount", and checks if that exists: exists(bufcount) *expand()* expand({expr}) Expand the file wildcards in {expr}. The result is a String. When there are several matches, they are separated by characters. [Note: in version 5.0 a space was used, which caused problems when a file name contains a space] For Unix, backticks can be used to get the output of any command. Example: > :let tagfiles = expand("`find . -name tags -print`") > :let &tags = substitute(tagfiles, "\n", ",", "g") If the expansion fails, the result is an empty string. When the result of {expr} starts with '%', '#' or '<', the expansion is done like for the |cmdline-special| variables with their associated modifiers. Here is a short overview: % current file name # alternate file name #n alternate file name n file name under the cursor autocmd file name autocmd buffer number sourced script file name word under the cursor WORD under the cursor Modifiers: :p expand to full path :h head (last path component removed) :t tail (last path component only) :r root (one extension removed) :e extension only Example: > :let &tags = expand("%:p:h") . "/tags" There cannot be white space between the variables and the following modifier. The |fnamemodify()| function can be used to modify normal file names. When using '%' or '#', and the current or alternate file name is not defined, an empty string is used. Using "%:p" in a buffer with no name, results in the current directory, with a '/' added. *filereadable()* filereadable({file}) The result is a Number, which is TRUE when a file with the name {file} exists, and can be read. If {file} doesn't exist, or is a directory, the result is FALSE. {file} is any expression, which is used as a String. *file_readable()* Obsolete name: file_readable(). *fnamemodify()* fnamemodify({fname}, {mods}) Modify file name {fname} accoding to {mods}. {mods} is a string of characters like it is used for file names on the command line. See |filename-modifiers|. Example: > :echo fnamemodify("main.c", ":p:h") results in: > /home/mool/vim/vim/src/ *getcwd()* getcwd() The result is a String, which is the name of the current working directory. *getline()* getline({lnum}) The result is a String, which is line {lnum} from the current buffer. Example: > getline(1) When {lnum} is a String that doesn't start with a digit, line() is called to translate the String into a Number. To get the line under the cursor: > getline(".") When {lnum} is smaller than 1 or bigger than the number of lines in the buffer, an empty string is returned. *has()* has({feature}) The result is a Number, which is 1 if the feature {feature} is supported, zero otherwise. The {feature} argument is a string. See |feature-list| below. *hlexists()* hlexists({name}) The result is a Number, which is non-zero if a highlight group called {name} exists. This is when the group has been defined in some way. Not necessarily when highlighting has been defined for it, it may also have been used for a syntax item. *highlight_exists()* Obsolete name: highlight_exists(). *hlID()* hlID({name}) The result is a Number, which is the ID of the highlight group with name {name}. When the highlight group doesn't exist, zero is returned. This can be used to retrieve information about the highlight group. For example, to get the background color of the "Comment" group: > :echo synIDattr(synIDtrans(hlID("Comment")), "bg") *highlightID()* Obsolete name: highlightID(). *hostname()* hostname() The result is a String, which is the name of the machine on which Vim is currently running. Machine names greater than 256 characters long are truncated. input({prompt}) *input()* The result is a String, which is whatever the user typed on the command-line. The parameter is either a prompt string, or a blank string (for no prompt). A '\n' can be used in the prompt to start a new line. The highlighting set with |:echohl| is used for the prompt. The input is entered just like a command-line, with the same editing commands and mappings. There is a separate history for lines typed for input(). NOTE: This must not be used in a startup file, for the versions that only run in GUI mode (e.g., the Win32 GUI). Example: > :let choice = input("What is your choice? ") *isdirectory()* isdirectory({directory}) The result is a Number, which is TRUE when a directory with the name {directory} exists. If {directory} doesn't exist, or isn't a directory, the result is FALSE. {directory} is any expression, which is used as a String. *line()* line({expr}) The result is a Number, which is the line number of the file position given with {expr}. The accepted positions are: . the cursor position $ the last line in the current buffer 'x position of mark x (if the mark is not set, 0 is returned) Note that only marks in the current file can be used. Examples: > line(".") line number of the cursor > line("'t") line number of mark t > line("'" . marker) line number of mark marker *match()* match({expr}, {pat}) The result is a Number, which gives the index in {expr} where {pat} matches. A match at the first character returns zero. If there is no match -1 is returned. Example: > :echo match("testing", "ing") results in "4". See |pattern| for the patterns that are accepted. The 'ignorecase' option is used to set the ignore-caseness of the pattern. 'smartcase' is NOT used. *matchend()* matchend({expr}, {pat}) Same as match(), but return the index of first character after the match. Example: > :echo matchend("testing", "ing") results in "7". *matchstr()* matchstr({expr}, {pat}) Same as match(), but return the matched string. Example: > :echo matchstr("testing", "ing") results in "ing". When there is no match "" is returned. *nr2char()* nr2char({expr}) Return a string with a single chararacter, which has the ASCII value {expr}. Examples: > nr2char(64) returns "@" > nr2char(32) returns " " *setline()* setline({lnum}, {line}) Set line {lnum} of the current buffer to {line}. If this succeeds, 0 is returned. If this fails (most likely because {lnum} is invalid) 1 is returned. Example: > :call setline(5, strftime("%c")) *strftime()* strftime({format}) The result is a String, which is the current date and time, as specified by the {format} string. See the manual page of the C function strftime() for the format. The maximum length of the result is 80 characters. Examples: > :echo strftime("%c") Sun Apr 27 11:49:23 1997 > :echo strftime("%Y %b %d %X") 1997 Apr 27 11:53:25 > :echo strftime("%y%m%d %T") 970427 11:53:55 > :echo strftime("%H:%M") 11:55 *strlen()* strlen({expr}) The result is a Number, which is the length of the String {expr}. *strpart()* strpart({src}, {start}, {len}) The result is a String, which is part of {src}, starting from character {start}, with the length {len}. When non-existing characters are included, this doesn't result in an error, the characters are simply omitted. > strpart("abcdefg", 3, 2) == "de" > strpart("abcdefg", -2, 4) == "ab" > strpart("abcdefg", 5, 4) == "fg" Note: To get the first character, {start} must be 0. For example, to get three characters under and after the cursor: > strpart(getline(line(".")), col(".") - 1, 3) *synID()* synID({line}, {col}, {trans}) The result is a Number, which is the syntax ID at the position {line} and {col} in the current window. The syntax ID can be used with |synIDattr()| and |synIDtrans()| to obtain syntax information about text. {col} is 1 for the leftmost column, {line} is 1 for the first line. When {trans} is non-zero, transparent items are reduced to the item that they reveal. This is useful when wanting to know the effective color. When {trans} is zero, the transparent item is returned. This is useful when wanting to know which syntax item is effective (e.g. inside parens). Warning: This function can be very slow. Best speed is obtained by going through the file in forward direction. Example (echos the name of the syntax item under the cursor): > :echo synIDattr(synID(line("."), col("."), 1), "name") *synIDattr()* synIDattr({synID}, {what} [, {mode}]) The result is a String, which is the {what} attribute of syntax ID {synID}. This can be used to obtain information about a syntax item. {mode} can be "gui", "cterm" or "term", to get the attributes for that mode. When {mode} is omitted, or an invalid value is used, the attributes for the currently active highlighting are used (GUI, cterm or term). Use synIDtrans() to follow linked highlight groups. {what} result "name" the name of the syntax item "fg" foreground color (GUI: color name, cterm: color number as a string, term: empty string) "bg" background color (like "fg") "fg#" like "fg", but name in "#RRGGBB" form "bg#" like "bg", but name in "#RRGGBB" form "bold" "1" if bold "italic" "1" if italic "reverse" "1" if reverse "inverse" "1" if inverse (= reverse) "underline" "1" if underlined When the GUI is not running or the cterm mode is asked for, "fg#" is equal to "fg" and "bg#" is equal to "bg". Example (echos the color of the syntax item under the cursor): > :echo synIDattr(synIDtrans(synID(line("."), col("."), 1)), "fg") *synIDtrans()* synIDtrans({synID}) The result is a Number, which is the translated syntax ID of {synID}. This is the syntax group ID of what is being used to highlight the character. Highlight links are followed. *substitute()* substitute({expr}, {pat}, {sub}, {flags}) The result is a String, which is a copy of {expr}, in which the first match of {pat} is replaced with {sub}. This works like the ":substitute" command (without any flags). But the 'magic' option is ignored, the {pat} is always processed as if 'magic' is set (to make scripts portable). And a "~" in {sub} is not replaced with the previous {sub}. When {pat} does not match in {expr}, {expr} is returned unmodified. When {flags} is "g", all matches of {pat} in {expr} are replaced. Otherwise {flags} should be "". Example: > :let &path = substitute(&path, ",\\=[^,]*$", "", "") This removes the last component of the 'path' option. > :echo substitute("testing", ".*", "\\U\\0", "") results in "TESTING". *tempname()* tempname() The result is a String, which is the name of a file that doesn't exist. It can be used for a temporary file. The name is different for each least 26 consecutive calls. Example: > let tmpfile = tempname() > exe "redir > " . tmpfile *virtcol()* virtcol({expr}) The result is a Number, which is the screen column of the file position given with {expr}. That is, the last screen position occupied by the character at that position, when the screen would be of unlimited width. When there is a at the position, the returned Number will be the column at the end of the . For example, for a in column 1, with 'ts' set to 8, it returns 8; The accepted positions are: . the cursor position 'x position of mark x (if the mark is not set, 0 is returned) Note that only marks in the current file can be used. Examples: > virtcol(".") with text "foo^Lbar", with cursor on the "^L", returns 5 > virtcol("'t") with text " there", with 't at 'h', returns 6 The first column is 1. 0 is returned for an error. *winbufnr()* winbufnr({nr}) The result is a Number, which is the number of the buffer associated with window {nr}. When {nr} is zero, the number of the buffer in the current window is returned. When window {nr} doesn't exist, -1 is returned. Example: > echo "The file in the current window is " . bufname(winbufnr(0)) *winheight()* winheight({nr}) The result is a Number, which is the height of window {nr}. When {nr} is zero, the height of the current window is returned. When window {nr} doesn't exist, -1 is returned. An existing window always has a height of zero or more. Examples: > echo "The current window has " . winheight(0) . " lines." *winnr()* winnr() The result is a Number, which is the number of the current window. The top window has number 1. *feature-list* There are two types of features: 1. Features that are only supported when they have been enabled when Vim was compiled |+feature-list|. Example: > :if has("cindent") 2. Features that are only supported when certain conditions have been met. Example: > :if has("gui_running") all_builtin_terms Compiled with all builtin terminals enabled. amiga Amiga version of Vim. arp Compiled with ARP support (Amiga). autocmd Compiled with autocommands support. beos BeOS version of Vim. browse Compiled with |:browse| support, and browse() will work. builtin_terms Compiled with some builtin terminals. cindent Compiled with 'cindent' support. cscope Compiled with |cscope| support. compatible Compiled to be very Vi compatible. debug Compiled with "DEBUG" defined. dialog_con Compiled with console dialog support. dialog_gui Compiled with GUI dialog support. digraphs Compiled with support for digraphs. dos32 32 bits DOS (DJGPP) version of Vim. dos16 16 bits DOS version of Vim. emacs_tags Compiled with support for Emacs tags. eval Compiled with expression evaluation support. Always true, of course! ex_extra Compiled with extra Ex commands |+ex_extra|. extra_search Compiled with support for |'incsearch'| and |'hlsearch'| farsi Compiled with Farsi support |farsi|. file_in_path Compiled with support for |gf| and || filetype Compiled with support for filetypes |+filetype| find_in_path Compiled with support for include file searches |+find_in_path|. fname_case Case in file names matters (for Amiga, MS-DOS, and Windows this is not present). fork Compiled to use fork()/exec() instead of system(). gui Compiled with GUI enabled. gui_athena Compiled with Athena GUI. gui_beos Compiled with BeOs GUI. gui_mac Compiled with Macintosh GUI. gui_motif Compiled with Motif GUI. gui_win32 Compiled with MS Windows Win32 GUI. gui_win32s idem, and Win32s system being used (Windows 3.1) gui_running Vim is running in the GUI, or it will start soon. insert_expand Compiled with support for CTRL-X expansion commands in Insert mode. langmap Compiled with 'langmap' support. lispindent Compiled with support for lisp indenting. mac Macintosh version of Vim. modify_fname Compiled with file name modifiers. |filename-modifiers| mouse Compiled with support mouse. mouse_dec Compiled with support for Dec terminal mouse. mouse_netterm Compiled with support for netterm mouse. mouse_xterm Compiled with support for xterm mouse. multi_byte Compiled with support for Korean et al. multi_byte_ime Compiled with support for IME input method ole Compiled with OLE automation support for Win32. perl Compiled with Perl interface. python Compiled with Python interface. quickfix Compiled with |quickfix| support. rightleft Compiled with 'rightleft' support. showcmd Compiled with 'showcmd' support. smartindent Compiled with 'smartindent' support. sniff Compiled with SniFF interface support. syntax Compiled with syntax highlighting support. syntax_items There are active syntax highlighting items for the current buffer. system Compiled to use system() instead of fork()/exec(). tag_binary Compiled with binary searching in tags files |tag-binary-search|. tag_old_static Compiled with support for old static tags |tag-old-static|. tag_any_white Compiled with support for any white characters in tags files |tag-any-white|. tcl Compiled with Tcl interface. terminfo Compiled with terminfo instead of termcap. textobjects Compiled with support for |text-objects|. tgetent Compiled with tgetent support, able to use a termcap or terminfo file. unix Unix version of Vim. user-commands User-defined commands. viminfo Compiled with viminfo support. vms VMS version of Vim. wildignore Compiled with 'wildignore' option win32 Win32 version of Vim (Windows 95/NT) writebackup Compiled with 'writebackup' default on. xterm_save Compiled with support for saving and restoring the xterm screen. x11 Compiled with X11 support. ============================================================================== 5. Defining functions *user-functions* New functions can be defined. These can be called with "Name()", just like builtin functions. The name must start with an uppercase letter, to avoid confusion with builtin functions. *:fu* *:function* :fu[nction] List all functions and their arguments. :fu[nction] {name} List function {name}. :fu[nction][!] {name}([arguments]) [range] [abort] Define a new function by the name {name}. The name must be made of alphanumeric characters and '_', and must start with a capital. An argument can be defined by giving its name. In the function this can then be used as "a:name" ("a:" for argument). Several arguments can be given, separated by commas. Finally, an argument "..." can be specified, which means that more arguments may be following. In the function they can be used as "a:1", "a:2", etc. "a:0" is set to the number of extra arguments (which can be 0). When not using "...", the number of arguments in a function call must be equal the number of named arguments. When using "...", the number of arguments may be larger. It is also possible to define a function without any arguments. You must still supply the () then. The body of the function follows in the next lines, until ":endfunction". When a function by this name already exists and [!] is not used an error message is given. When [!] is used, an existing function is silently replaced. When the [range] argument is added, the function is expected to take care of a range itself. The range is passed as "a:firstline" and "a:lastline". If [range] is excluded, a ":call" with a range will call the function for each line, with the cursor on the start of each line. When the [abort] argument is added, the function will abort as soon as an error is detected. The last used search pattern and the redo command "." will not be changed by the function. *:endf* *:endfunction* :endf[unction] The end of a function definition. *:delf* *:delfunction* :delf[unction] {name} Delete function {name}. *:retu* *:return* :retu[rn] [expr] Return from a function. When "[expr]" is given, it is evaluated and returned as the result of the function. If "[expr]" is not given, the number 0 is returned. When a function ends without an explicit ":return", the number 0 is returned. Note that there is no check for unreachable lines, thus there is no warning if commands follow ":return". Inside a function variables can be used. These are local variables, which will disappear when the function returns. Global variables need to be accessed with "g:". Example: > :function Table(title, ...) > : echohl Title > : echo a:title > : echohl None > : let idx = 1 > : while idx <= a:0 > : exe "echo a:" . idx > : let idx = idx + 1 > : endwhile > : return idx > :endfunction This function can then be called with: > let lines = Table("Table", "line1", "line2") > let lines = Table("Empty Table") To return more than one value, pass the name of a global variable: > :function Compute(n1, n2, divname) > : if a:n2 == 0 > : return "fail" > : endif > : exe "let " . a:divname . " = ". a:n1 / a:n2 > : return "ok" > :endfunction This function can then be called with: > :let success = Compute(13, 1324, "div") > :if success == "ok" > : echo div > :endif *:cal* *:call* :[range]cal[l] {name}([arguments]) Call a function. The name of the function and its arguments are as before. Without a range and for functions that accept a range, the function is called once, with the cursor at the current position. When a range is given and the function doesn't handle it itself, the function is executed for each line in the range, with the cursor in the first column of that line. The cursor is left at the last line (possibly moved by the last function call). The arguments are re-evaluated for each line. Thus this works: > :function Mynumber(arg) > : echo line(".") . " " . a:arg > :endfunction > :1,5call Mynumber(getline(".")) The recursiveness of user functions is restricted with the |'maxfuncdepth'| option. ============================================================================== 6. Commands *expression-commands* :let {var-name} = {expr1} *:let* Set internal variable {var-name} to the result of the expression {expr1}. The variable will get the type from the {expr}. if {var-name} didn't exist yet, it is created. :let ${env-name} = {expr1} *:let-environment* *:let-$* Set environment variable {env-name} to the result of the expression {expr1}. The type is always String. :let @{reg-name} = {expr1} *:let-register* *:let-@* Write the result of the expression {expr1} in register {reg-name}. {reg-name} must be a single letter, and must be the name of a writable register (see |registers|). "@@" can be used for the unnamed register. If the result of {expr1} ends in a or , the register will be linewise, otherwise it will be set to characterwise. :let &{option-name} = {expr1} *:let-option* *:let-star* Set option {option-name} to the result of the expression {expr1}. The type of the option is always used. *:unlet* *:unl* :unl[et][!] {var-name} ... Remove the internal variable {var-name}. Several variable names can be given, they are all removed. With [!] no error message is given for non-existing variables. :if {expr1} *:if* *:endif* *:en* :en[dif] Execute the commands until the next matching ":else" or ":endif" if {expr1} evaluates to non-zero. From Vim version 4.5 until 5.0, every Ex command in between the ":if" and ":endif" is ignored. These two commands were just to allow for future expansions in a backwards compatible way. Nesting was allowed. Note that any ":else" or ":elseif" was ignored, the "else" part was not executed either. You can use this to remain compatible with older versions: > :if version >= 500 > : version-5-specific-commands > :endif *:else* *:el* :el[se] Execute the commands until the next matching ":else" or ":endif" if they previously were not being executed. *:elseif* *:elsei* :elsei[f] {expr1} Short for ":else" ":if", with the addition that there is no extra ":endif". :wh[ile] {expr1} *:while* *:endwhile* *:wh* *:endw* :endw[hile] Repeat the commands between ":while" and ":endwhile", as long as {expr1} evaluates to non-zero. When an error is detected from a command inside the loop, execution continues after the "endwhile". NOTE: The ":append" and ":insert" commands don't work properly inside a ":while" loop. *:continue* *:con* :con[tinue] When used inside a ":while", jumps back to the ":while". *:break* *:brea* :brea[k] When used inside a ":while", skips to the command after the matching ":endwhile". *:ec* *:echo* :ec[ho] {expr1} .. Echoes each {expr1}, with a space in between and a terminating . Also see |:comment|. Example: > :echo "the value of 'shell' is" &shell *:echon* :echon {expr1} .. Echoes each {expr1}, without anything added. Also see |:comment|. Example: > :echon "the value of 'shell' is " &shell Note the difference between using ":echo", which is a Vim command, and ":!echo", which is an external shell command: > :!echo % --> filename The arguments of ":!" are expanded, see |:_%|. > :!echo "%" --> filename or "filename" Like the previous example. Whether you see the double quotes or not depends on your 'shell'. > :echo % --> nothing The '%' is an illegal character in an expression. > :echo "%" --> % This just echoes the '%' character. > :echo expand("%") --> filename This calls the expand() function to expand the '%'. *:echoh* *:echohl* :echoh[l] {name} Use the highlight group {name} for the following ":echo[n]" commands. Example: > :echohl WarningMsg | echo "Don't panic!" | echohl None Don't forget to set the group back to "None", otherwise all following echo's will be highlighted. *:exe* *:execute* :exe[cute] {expr1} .. Executes the string that results from the evaluation of {expr1} as an Ex command. Multiple arguments are concatenated, with a space in between. Examples: > :execute "buffer " nextbuf > :execute "normal " count . "w" Execute can be used to append a next command to commands that don't accept a '|'. Example: > :execute '!ls' | echo "theend" Note: The executed string may be any command-line, but you cannot start or end a "while" or "if" command. Thus this is illegal: > :execute 'while i > 5' > :execute 'echo "test" | break' It is allowed to have a "while" or "if" command completely in the executed string: > :execute 'while i < 5 | echo i | let i = i + 1 | endwhile' *:comment* ":execute", ":echo" and ":echon" cannot be followed by a comment directly, because they see the '"' as the start of a string. But, you can use '|' followed by a comment. Example: > :echo "foo" | "this is a comment vim:tw=78:ts=8:sw=8: