summaryrefslogtreecommitdiff
path: root/runtime/macros/matchit.txt
diff options
context:
space:
mode:
Diffstat (limited to 'runtime/macros/matchit.txt')
-rw-r--r--runtime/macros/matchit.txt402
1 files changed, 402 insertions, 0 deletions
diff --git a/runtime/macros/matchit.txt b/runtime/macros/matchit.txt
new file mode 100644
index 000000000..8ea4de5f2
--- /dev/null
+++ b/runtime/macros/matchit.txt
@@ -0,0 +1,402 @@
+*matchit.txt* Extended "%" matching
+
+For instructions on installing this file, type
+ :help matchit-install
+inside Vim.
+
+For Vim version 6.3. Last change: 2004 May 12
+
+
+ VIM REFERENCE MANUAL by Benji Fisher
+
+*matchit* *matchit.vim*
+
+1. Extended matching with "%" |matchit-intro|
+2. Activation |matchit-activate|
+3. Configuration |matchit-configure|
+4. Supporting a New Language |matchit-newlang|
+5. Known Bugs and Limitations |matchit-bugs|
+
+The functionality mentioned here is a plugin, see |add-plugin|.
+This plugin is only available if 'compatible' is not set.
+You can avoid loading this plugin by setting the "loaded_matchit" variable
+in your |vimrc| file: >
+ :let loaded_matchit = 1
+
+{Vi does not have any of this}
+
+==============================================================================
+1. Extended matching with "%" *matchit-intro*
+
+ *matchit-%*
+% Cycle forward through matching groups, such as "if", "else", "endif",
+ as specified by |b:match_words|.
+
+ *g%* *v_g%* *o_g%*
+g% Cycle backwards through matching groups, as specified by
+ |b:match_words|. For example, go from "endif" to "else" to "if".
+
+ *[%* *v_[%* *o_[%*
+[% Go to [count] previous unmatched group, as specified by
+ |b:match_words|. Similar to |[{|.
+
+ *]%* *v_]%* *o_]%*
+]% Go to [count] next unmatched group, as specified by
+ |b:match_words|. Similar to |]}|.
+
+ *v_a%*
+a% In Visual mode, select the matching group, as specified by
+ |b:match_words|, containing the cursor. Similar to |v_a[|.
+ A [count] is ignored, and only the first character of the closing
+ pattern is selected.
+
+In Vim, as in plain vi, the percent key, |%|, jumps the cursor from a brace,
+bracket, or paren to its match. This can be configured with the 'matchpairs'
+option. The matchit plugin extends this in several ways:
+
+ You can match whole words, such as "if" and "endif", not just
+ single characters. You can also specify a |regular-expression|.
+ You can define groups with more than two words, such as "if",
+ "else", "endif". Banging on the "%" key will cycle from the "if" to
+ the first "else", the next "else", ..., the closing "endif", and back
+ to the opening "if". Nested structures are skipped. Using |g%| goes
+ in the reverse direction.
+ By default, words inside comments and strings are ignored, unless
+ the cursor is inside a comment or string when you type "%". If the
+ only thing you want to do is modify the behavior of "%" so that it
+ behaves this way, you can >
+ :let b:match_words = &matchpairs
+<
+See |matchit-details| for details on what the script does, and |b:match_words|
+for how to specify matching patterns.
+
+MODES: *matchit-modes* *matchit-v_%* *matchit-o_%*
+
+Mostly, % and related motions (|g%| and |[%| and |]%|) work just like built-in
+|motion| commands in |Operator-pending| and |Visual| modes. However, you
+cannot make these motions |linewise| or |characterwise|, since the |:omap|s
+that define them start with "v" in order to make the default behavior
+inclusive. (See |o_v|.) In other words, "dV%" will not work. The
+work-around is to go through Visual mode: "V%d" will work.
+
+LANGUAGES: *matchit-languages*
+
+Currently, the following languages are supported: Ada, ASP with VBS, Csh,
+DTD, Entity, Essbase, Fortran, HTML, JSP (same as HTML), LaTeX, Lua, Pascal,
+SGML, Shell, Tcsh, Vim, XML. Other languages may already have support via
+|filetype-plugin|s.
+
+To support a new language, see |matchit-newlang| below.
+
+DETAILS: *matchit-details* *matchit-parse*
+
+Here is an outline of what matchit.vim does each time you hit the "%" key. If
+there are |backref|s in |b:match_words| then the first step is to produce a
+version in which these back references have been eliminated; if there are no
+|backref|s then this step is skipped. This step is called parsing. For
+example, "\(foo\|bar\):end\1" is parsed to yield
+"\(foo\|bar\):end\(foo\|bar\)". This can get tricky, especially if there are
+nested groups. If debugging is turned on, the parsed version is saved as
+|b:match_pat|.
+
+ *matchit-choose*
+Next, the script looks for a word on the current line that matches the pattern
+just constructed. It includes the patterns from the 'matchpairs' option.
+The goal is to do what you expect, which turns out to be a little complicated.
+The script follows these rules:
+
+ Insist on a match that ends on or after the cursor.
+ Prefer a match that includes the cursor position (that is, one that
+ starts on or before the cursor).
+ Prefer a match that starts as close to the cursor as possible.
+ Prefer a match in |b:match_words| to a match in 'matchpairs'.
+ If more than one pattern in |b:match_words| matches, choose the one
+ that is listed first.
+
+Examples:
+
+ Suppose you >
+ :let b:match_words = '<:>,<tag>:</tag>'
+< and hit "%" with the cursor on or before the "<" in "a <tag> is born".
+ The pattern '<' comes first, so it is preferred over '<tag>', which
+ also matches. If the cursor is on the "t", however, then '<tag>' is
+ preferred, because this matches a bit of text containing the cursor.
+ If the two groups of patterns were reversed then '<' would never be
+ preferred.
+
+ Suppose you >
+ :let b:match_words = 'if:end if'
+< (Note the space!) and hit "%" with the cursor at the end of "end if".
+ Then "if" matches, which is probably not what you want, but if the
+ cursor starts on the "end " then "end if" is chosen. (You can avoid
+ this problem by using a more complicated pattern.)
+
+If there is no match, the script falls back on the usual behavior of |%|. If
+debugging is turned on, the matched bit of text is saved as |b:match_match|
+and the cursor column of the start of the match is saved as |b:match_col|.
+
+Next, the script looks through |b:match_words| (original and parsed versions)
+for the group and pattern that match. If debugging is turned on, the group is
+saved as |b:match_ini| (the first pattern) and |b:match_tail| (the rest). If
+there are |backref|s then, in addition, the matching pattern is saved as
+|b:match_word| and a table of translations is saved as |b:match_table|. If
+there are |backref|s, these are determined from the matching pattern and
+|b:match_match| and substituted into each pattern in the matching group.
+
+The script decides whether to search forwards or backwards and chooses
+arguments for the |searchpair()| function. Then, the cursor is moved to the
+start of the match, and |searchpair()| is called. By default, matching
+structures inside strings and comments are ignored. This can be changed by
+setting |b:match_skip|.
+
+==============================================================================
+2. Activation *matchit-activate*
+
+You can use this script as a plugin, by copying it to your plugin directory.
+See |add-global-plugin| for instructions. You can also add a line to your
+|vimrc| file, such as >
+ :source $VIMRUNTIME/macros/matchit.vim
+or >
+ :runtime macros/matchit.vim
+Either way, the script should start working the next time you start up Vim.
+
+The script does nothing unless it finds a |buffer-variable| named
+|b:match_words|. The script contains autocommands that set this variable for
+various file types: see |matchit-languages| above. For a new language, you
+can add autocommands to the script or to your vimrc file, but the recommended
+method is to add a line such as >
+ let b:match_words = '\<foo\>:\<bar\>'
+to the |filetype-plugin| for your language. See |b:match_words| below for how
+this variable is interpreted.
+
+TROUBLESHOOTING *matchit-troubleshoot*
+
+The script should work in most installations of Vim. It may not work if Vim
+was compiled with a minimal feature set, for example if the |+syntax| option
+was not enabled. If your Vim has support for syntax compiled in, but you do
+not have |syntax| highlighting turned on, matchit.vim should work, but it may
+fail to skip matching groups in comments and strings. If the |filetype|
+mechanism is turned off, the |b:match_words| variable will probably not be
+defined automatically.
+
+==============================================================================
+3. Configuration *matchit-configure*
+
+There are several variables that govern the behavior of matchit.vim. Note
+that these are variables local to the buffer, not options, so use |:let| to
+define them, not |:set|. Some of these variables have values that matter; for
+others, it only matters whether the variable has been defined. All of these
+can be defined in the |filetype-plugin| or autocommand that defines
+|b:match_words| or "on the fly."
+
+The main variable is |b:match_words|. It is described in the section below on
+supporting a new language.
+
+ *MatchError* *matchit-hl* *matchit-highlight*
+MatchError is the highlight group for error messages from the script. By
+default, it is linked to WarningMsg. If you do not want to be bothered by
+error messages, you can define this to be something invisible. For example,
+if you use the GUI version of Vim and your command line is normally white, you
+can do >
+ :hi MatchError guifg=white guibg=white
+<
+ *b:match_ignorecase*
+If you >
+ :let b:match_ignorecase = 1
+then matchit.vim acts as if 'ignorecase' is set: for example, "end" and "END"
+are equivalent. If you >
+ :let b:match_ignorecase = 0
+then matchit.vim treats "end" and "END" differently. (There will be no
+b:match_infercase option unless someone requests it.)
+
+ *b:match_debug*
+Define b:match_debug if you want debugging information to be saved. See
+|matchit-debug|, below.
+
+ *b:match_skip*
+If b:match_skip is defined, it is passed as the skip argument to
+|searchpair()|. This controls when matching structures are skipped, or
+ignored. By default, they are ignored inside comments and strings, as
+determined by the |syntax| mechanism. (If syntax highlighting is turned off,
+nothing is skipped.) You can set b:match_skip to a string, which evaluates to
+a non-zero, numerical value if the match is to be skipped or zero if the match
+should not be skipped. In addition, the following special values are
+supported by matchit.vim:
+ s:foo becomes (current syntax item) =~ foo
+ S:foo becomes (current syntax item) !~ foo
+ r:foo becomes (line before cursor) =~ foo
+ R:foo becomes (line before cursor) !~ foo
+(The "s" is meant to suggest "syntax", and the "r" is meant to suggest
+"regular expression".)
+
+Examples:
+
+ You can get the default behavior with >
+ :let b:match_skip = 's:comment\|string'
+<
+ If you want to skip matching structures unless they are at the start
+ of the line (ignoring whitespace) then you can >
+ :let b:match_skip = 'R:^\s*'
+< Do not do this if strings or comments can span several lines, since
+ the normal syntax checking will not be done if you set b:match_skip.
+
+ In LaTeX, since "%" is used as the comment character, you can >
+ :let b:match_skip = 'r:%'
+< Unfortunately, this will skip anything after "\%", an escaped "%". To
+ allow for this, and also "\\%" (an excaped backslash followed by the
+ comment character) you can >
+ :let b:match_skip = 'r:\(^\|[^\\]\)\(\\\\\)*%'
+<
+ See the $VIMRUNTIME/syntax/vim.vim for an example that uses both
+ syntax and a regular expression.
+
+==============================================================================
+4. Supporting a New Language *matchit-newlang*
+ *b:match_words*
+In order for matchit.vim to support a new language, you must define a suitable
+pattern for |b:match_words|. You may also want to set some of the
+|matchit-configure| variables, as described above. If your language has a
+complicated syntax, or many keywords, you will need to know something about
+Vim's |regular-expression|s.
+
+The format for |b:match_words| is similar to that of the 'matchpairs' option:
+it is a comma (,)-separated list of groups; each group is a colon(:)-separated
+list of patterns (regular expressions). It is OK to have only one group; the
+effect is undefined if a group has only one pattern. A simple example is >
+ :let b:match_words = '\<if\>:\<endif\>,'
+ \ . '\<while\>:\<continue\>:\<break\>:\<endwhile\>'
+(In Vim regular expressions, |\<| and |\>| denote word boundaries. Thus "if"
+matches the end of "endif" but "\<if\>" does not.) Then banging on the "%"
+key will bounce the cursor between "if" and the matching "endif"; and from
+"while" to any matching "continue" or "break", then to the matching "endwhile"
+and back to the "while". It is almost always easier to use |literal-string|s
+(single quotes) as above: '\<if\>' rather than "\\<if\\>" and so on.
+
+Exception: If the ":" character does not appear in b:match_words, then it is
+treated as an expression to be evaluated. For example, >
+ :let b:match_words = 'GetMatchWords()'
+allows you to define a function. This can return a different string depending
+on the current syntax, for example.
+
+Once you have defined the appropriate value of |b:match_words|, you will
+probably want to have this set automatically each time you edit the
+appropriate file type. The recommended way to do this is by adding the
+definition to a |filetype-plugin| file.
+
+Tips: Be careful that your initial pattern does not match your final pattern.
+See the example above for the use of word-boundary expressions. It is usually
+better to use ".\{-}" (as many as necessary) instead of ".*" (as many as
+possible). See |\{-|. For example, in the string "<tag>label</tag>", "<.*>"
+matches the whole string whereas "<.\{-}>" and "<[^>]*>" match "<tag>" and
+"</tag>".
+
+ *matchit-spaces* *matchit-s:notend*
+If "if" is to be paired with "end if" (Note the space!) then word boundaries
+are not enough. Instead, define a regular expression s:notend that will match
+anything but "end" and use it as follows: >
+ :let s:notend = '\%(\<end\s\+\)\@<!'
+ :let b:match_words = s:notend . '\<if\>:\<end\s\+if\>'
+< *matchit-s:sol*
+This is a simplified version of what is done for Ada. The s:notend is a
+|script-variable|. Similarly, you may want to define a start-of-line regular
+expression >
+ :let s:sol = '\%(^\|;\)\s*'
+if keywords are only recognized after the start of a line or after a
+semicolon (;), with optional white space.
+
+ *matchit-backref* *matchit-\1*
+In any group, the expressions |\1|, |\2|, ..., |\9| refer to parts of the
+INITIAL pattern enclosed in |\(|escaped parentheses|\)|. These are referred
+to as back references, or backrefs. For example, >
+ :let b:match_words = '\<b\(o\+\)\>:\(h\)\1\>'
+means that "bo" pairs with "ho" and "boo" pairs with "hoo" and so on. Note
+that "\1" does not refer to the "\(h\)" in this example. If you have
+"\(nested \(parentheses\)\) then "\d" refers to the d-th "\(" and everything
+up to and including the matching "\)": in "\(nested\(parentheses\)\)", "\1"
+refers to everything and "\2" refers to "\(parentheses\)". If you use a
+variable such as |s:notend| or |s:sol| in the previous paragraph then remember
+to count any "\(" patterns in this variable. You do not have to count groups
+defined by |\%(\)|.
+
+It should be possible to resolve back references from any pattern in the
+group. For example, >
+ :let b:match_words = '\(foo\)\(bar\):more\1:and\2:end\1\2'
+would not work because "\2" cannot be determined from "morefoo" and "\1"
+cannot be determined from "andbar". On the other hand, >
+ :let b:match_words = '\(\(foo\)\(bar\)\):\3\2:end\1'
+should work (and have the same effect as "foobar:barfoo:endfoobar"), although
+this has not been thoroughly tested.
+
+You can use |zero-width| patterns such as |\@<=| and |\zs|. (The latter has
+not been thouroughly tested in matchit.vim.) For example, if the keyword "if"
+must occur at the start of the line, with optional white space, you might use
+the pattern "\(^\s*\)\@<=if" so that the cursor will end on the "i" instead of
+at the start of the line. For another example, if HTML had only one tag then
+one could >
+ :let b:match_words = '<:>,<\@<=tag>:<\@<=/tag>'
+so that "%" can bounce between matching "<" and ">" pairs or (starting on
+"tag" or "/tag") between matching tags. Without the |\@<=|, the script would
+bounce from "tag" to the "<" in "</tag>", and another "%" would not take you
+back to where you started.
+
+DEBUGGING *matchit-debug* *:MatchDebug*
+
+If you are having trouble figuring out the appropriate definition of
+|b:match_words| then you can take advantage of the same information I use when
+debugging the script. This is especially true if you are not sure whether
+your patterns or my script are at fault! To make this more convenient, I have
+made the command :MatchDebug, which defines the variable |b:match_debug| and
+creates a Matchit menu. This menu makes it convenient to check the values of
+the variables described below. You will probably also want to read
+|matchit-details| above.
+
+Defining the variable |b:match_debug| causes the script to set the following
+variables, each time you hit the "%" key. Several of these are only defined
+if |b:match_words| includes |backref|s.
+
+ *b:match_pat*
+The b:match_pat variable is set to |b:match_words| with |backref|s parsed.
+ *b:match_match*
+The b:match_match variable is set to the bit of text that is recognized as a
+match.
+ *b:match_col*
+The b:match_col variable is set to the cursor column of the start of the
+matching text.
+ *b:match_wholeBR*
+The b:match_wholeBR variable is set to the comma-separated group of patterns
+that matches, with |backref|s unparsed.
+ *b:match_iniBR*
+The b:match_iniBR variable is set to the first pattern in |b:match_wholeBR|.
+ *b:match_ini*
+The b:match_ini variable is set to the first pattern in |b:match_wholeBR|,
+with |backref|s resolved from |b:match_match|.
+ *b:match_tail*
+The b:match_tail variable is set to the remaining patterns in
+|b:match_wholeBR|, with |backref|s resolved from |b:match_match|.
+ *b:match_word*
+The b:match_word variable is set to the pattern from |b:match_wholeBR| that
+matches |b:match_match|.
+ *b:match_table*
+The back reference '\'.d refers to the same thing as '\'.b:match_table[d] in
+|b:match_word|.
+
+==============================================================================
+5. Known Bugs and Limitations *matchit-bugs*
+
+Just because I know about a bug does not mean that it is on my todo list. I
+try to respond to reports of bugs that cause real problems. If it does not
+cause serious problems, or if there is a work-around, a bug may sit there for
+a while. Moral: if a bug (known or not) bothers you, let me know.
+
+The various |:vmap|s defined in the script (%, |g%|, |[%|, |]%|, |a%|) may
+have undesired effects in Select mode |Select-mode-mapping|. At least, if you
+want to replace the selection with any character in "ag%[]" there will be a
+pause of |'updatetime'| first.
+
+It would be nice if "\0" were recognized as the entire pattern. That is, it
+would be nice if "foo:\end\0" had the same effect as "\(foo\):\end\1". I may
+try to implement this in a future version. (This is not so easy to arrange as
+you might think!)
+
+==============================================================================
+vim:tw=78:fo=tcq2: