mirror of
https://github.com/neovim/neovim.git
synced 2024-12-29 14:41:06 -07:00
98053f0f9f
Reviewed-by: Scott Prager <splinterofchaos@gmail.com> Reviewed-by: Michael Reed <m.reed@mykolab.com>
366 lines
17 KiB
Plaintext
366 lines
17 KiB
Plaintext
*pi_matchit.txt* Extended "%" matching
|
|
|
|
For Vim version 6.3. Last change: 2015 May 21
|
|
|
|
*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|.
|
|
You can avoid loading this plugin by setting the "loaded_matchit" variable
|
|
in your |vimrc| file: >
|
|
:let loaded_matchit = 1
|
|
|
|
==============================================================================
|
|
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 "if" to "endif" to "else".
|
|
|
|
*[%* *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 |]}|.
|
|
|
|
*a%* *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 do not have to define |b:match_words|, since the
|
|
script uses the 'matchpairs' option as well as this variable.
|
|
|
|
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
|
|
the default |filetype-plugin|s in the standard vim distribution.
|
|
|
|
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 backrefs 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
|
|
backrefs 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.
|
|
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 cursor does not move. (Before version 1.13 of the
|
|
script, it would fall 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 backrefs 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 backrefs, 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*
|
|
|
|
For a new language, you can add a line such as >
|
|
let b:match_words = '\<foo\>:\<bar\>'
|
|
to the corresponding |filetype-plugin|. See |b:match_words| below for how
|
|
this variable is interpreted.
|
|
|
|
==============================================================================
|
|
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/ftplugin/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). Commas and backslashes that are part
|
|
of a pattern should be escaped with backslashes ('\:' and '\,'). 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` (see |/\1|) 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 backrefs.
|
|
|
|
*b:match_pat*
|
|
The b:match_pat variable is set to |b:match_words| with backrefs 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 backrefs 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 backrefs resolved from |b:match_match|.
|
|
*b:match_tail*
|
|
The b:match_tail variable is set to the remaining patterns in
|
|
|b:match_wholeBR|, with backrefs 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*
|
|
|
|
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".
|
|
|
|
==============================================================================
|
|
vim:tw=78:ts=8:noet:ft=help:norl:
|