1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
|
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<!--
$Id: modes.html,v 1.4 2009/12/29 11:40:09 tom Exp $
-->
<HTML>
<HEAD>
<TITLE>
Major (and minor) modes in Vile
</TITLE>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<link rev="made" href="mailto:dickey@invisible-island.net">
<link rel="SHORTCUT ICON" href="/img/icons/vile.ico" type="image/x-icon">
</HEAD>
<BODY>
<h1 id="toplevel-id"><a name="toplevel">Major (and minor) modes in Vile</a></h1>
<p>
This document was originally written in May, 1998, and has been updated
periodically to reflect the proposed implementation of and use of major modes
in vile.
<p>
My goal was to extend the notion of the C mode (cmode)
to allow runtime definable major modes.
<p>
Originally, vile supported a C mode that included a collection of modes
useful for editing C program source:
<ul>
<li>c-suffixes
<li>c-tabstop
<li>c-shiftwidth
</ul><p>
as well as this builtin functionality:
<ul>
<li>autoindention of C statements taking into account curly braces
<li>fence matching for /*...*/ comments and C preprocessor statements
<li>comment formatting
</ul><p>
Both the modes and functionality are extensions of other features in
vile. It would be useful to combine modes to support other languages
in a similar fashion. Likewise, the autoindention, etc., could be
parameterized and made reusable to support other languages. For an
initial implementation, I focused on the combining of modes,
providing a structure for the parameterization.
<p>
One thing that was not clear to many users was the manner in which the C
mode was attached to a buffer. It was set as a boolean - if active before
a buffer was loaded, then vile checked the file suffix to see if it matched
the c-suffixes mode, and if so, set the C mode for the buffer. C mode
could also be explicitly set by a ":setl cmode", and unset by ":setl
nocmode". In the new scheme,
<ul>
<li>vile searches the list of all active majormodes, first
testing if any match with the majormode's suffixes, then if
any preamble (first line regular expression) matches.
<p>
The search is in normally alphabetic order, by majormode name.
The first match each, of suffixes and preamble terminate the
search, but a match of suffixes overrides a match of preamble.
Use "after" and "before" qualifiers to handle special cases.
<p>
In rare circumstances, both suffixes and preamble are needed to
distinguish a given mode from another. Use
<!--{{atr2html--><p style="font-family: monospace;">
qualifiers=all<br>
<!--atr2html}}--></p>
to specify this. The default, "qualifiers=any", allows either
suffixes or preamble to determine the majormode.
<p>
The suffixes and preamble rules can be overridden altogether by
specifying $majormode-hook to a script which sets the majormode
for the current buffer.
<li>majormodes can be disabled (e.g., ":set nocmode"), as before.
However, there is no global sense of majormode; unsetting a
buffer's local value of a majormode simply makes it not have a
majormode associated with it.
</ul>
<h2 id="neededcommands-id"><a name="neededcommands">Commands</a></h2>
<p>
These are the commands which I think are necessary:
<ul>
<li>define-majormode {majormode}
<li>define-submode {majormode} {minormode}[={value}]
<li>remove-majormode {majormode}
<li>remove-submode {majormode} {minormode}
<li>setl {majormode}
<li>setl no{majormode}
</ul><p>
The {majormode} is a new symbol.
<p>
The {minormode} can be any one of the existing buffer modes, except for
a {majormode}. To make name-completion simple, we use the term 'submode'.
<h3 id="example-id"><a name="example">Example</a></h3>
<!--{{atr2html--><p style="font-family: monospace;">
<strong><font color="#000080">define-majormode</font></strong> <strong><font color="#000080">c</font></strong><br>
<font color="#800000">; Declares a mode 'c', and corresponding symbol 'cmode'</font><br>
<br>
<strong><font color="#000080">define-submode</font></strong> <strong><font color="#000080">c</font></strong> <strong><font color="#000080">suffixes</font></strong><strong><font color="#800000">=</font></strong><font color="#800080">"\\.\\(\\([Cchisyl]\\)\\|CC\\|cc|cpp\\|cxx\\|hxx\\|scm\\)$"</font><br>
<font color="#800000">; Specifies the filename suffixes which control whether a newly-loaded</font><br>
<font color="#800000">; buffer is set to 'c' mode.</font><br>
<br>
<strong><font color="#000080">define-submode</font></strong> <strong><font color="#000080">c</font></strong> <strong><font color="#000080">tabstop</font></strong><strong><font color="#800000">=</font></strong><strong><font color="#008080">4</font></strong><br>
<strong><font color="#000080">define-submode</font></strong> <strong><font color="#000080">c</font></strong> <strong><font color="#000080">shiftwidth</font></strong><strong><font color="#800000">=</font></strong><strong><font color="#008080">4</font></strong><br>
<font color="#800000">; Defines the 'c' tabstop and shiftwidth. If no "define-submode"</font><br>
<font color="#800000">; command is given, no separate symbol is defined.</font><br>
<!--atr2html}}--></p>
As an example, to define a new major mode for perl programming, you might
include the following in your .vilerc file:
<!--{{atr2html--><p style="font-family: monospace;">
<strong><font color="#000080">define-majormode</font></strong> <strong><font color="#000080">perl</font></strong><br>
<strong><font color="#000080">define-submode</font></strong> <strong><font color="#000080">perl</font></strong> <strong><font color="#000080">preamble</font></strong> <font color="#800080">"^#.*perl\\>"</font><br>
<strong><font color="#000080">define-submode</font></strong> <strong><font color="#000080">perl</font></strong> <strong><font color="#000080">suffixes</font></strong> <font color="#800080">'\.\(pm\|t\)$'</font><br>
<strong><font color="#000080">define-submode</font></strong> <strong><font color="#000080">perl</font></strong> <strong><font color="#000080">shiftwidth</font></strong> <strong><font color="#008080">4</font></strong><br>
<!--atr2html}}--></p>
To avoid the tediousness of this syntax, use the ~with and ~endwidth
keywords, like so:
<!--{{atr2html--><p style="font-family: monospace;">
<strong><font color="#000080">define-majormode</font></strong> <strong><font color="#000080">perl</font></strong><br>
<font color="#008000">~with</font> <strong><font color="#000080">define-submode</font></strong> <strong><font color="#000080">perl</font></strong><br>
<strong><font color="#000080">preamble</font></strong> <font color="#800080">"^#.*perl\\>"</font><br>
<strong><font color="#000080">suffixes</font></strong> <font color="#800080">'\.\(pm\|t\)$'</font><br>
<strong><font color="#000080">shiftwidth</font></strong> <strong><font color="#008080">4</font></strong><br>
<font color="#008000">~endwith</font><br>
<!--atr2html}}--></p>
You can define several regions using ~with and (after the first) ~elsewith
blocks. Each block specifies a set of tokens which are substituted at the
beginning of each line. Each ~elsewith block should have a group identifier
to distinguish it from the others. The reason for providing multiple
blocks is to implement complex fence-matching for different language features.
<p>
For example, in the definition of cshmode, the symbols "fence-XXX" give
patterns which vile can use to move the cursor from one if/elif/else/fi
marker to the next as you press "%". The other settings such as "suf"
in the first block are settings that apply to the majormode itself:
<!--{{atr2html--><p style="font-family: monospace;">
<strong><font color="#000080">define-mode</font></strong> <em>csh</em><br>
<font color="#008000">~with</font> <strong><font color="#000080">define-submode</font></strong> <em>csh</em><br>
<strong><font color="#000080">suf</font></strong> <font color="#800080">'\.\(csh[^/]*\|login\|logout\)$'</font><br>
<strong><font color="#000080">pre</font></strong> <font color="#800080">'^#!\s*\/.*csh\>\(\s*-[a-z]\+\)*\s*$'</font><br>
<strong><font color="#000080">filtername</font></strong> <font color="#800080">'vile-sh-filt -k csh'</font><br>
<strong><font color="#000080">comment-prefix</font></strong> <font color="#800080">'^\s*#'</font><br>
<strong><font color="#000080">comments</font></strong> <font color="#800080">'^\s*#\s*$'</font><br>
<strong><font color="#000080">fence-if</font></strong> <font color="#800080">'^\s*\<if\>.*\<then\>'</font><br>
<strong><font color="#000080">fence-elif</font></strong> <font color="#800080">'^\s*\<else\s*if\>'</font><br>
<strong><font color="#000080">fence-else</font></strong> <font color="#800080">'^\s*\<else\>'</font><br>
<strong><font color="#000080">fence-fi</font></strong> <font color="#800080">'^\s*\<endif\>'</font><br>
<font color="#008000">~elsewith</font> <strong><font color="#000080">define-submode</font></strong> <em>csh</em> <strong><font color="#000080">group</font></strong> <font color="#800080">'case'</font><br>
<strong><font color="#000080">fence-if</font></strong> <font color="#800080">'^\s*\<switch\>\s*(.*)'</font><br>
<strong><font color="#000080">fence-elif</font></strong> <font color="#800080">'^\s*\<case\>.*:'</font><br>
<strong><font color="#000080">fence-else</font></strong> <font color="#800080">'^\s*\<default\>\s*:'</font><br>
<strong><font color="#000080">fence-fi</font></strong> <font color="#800080">'^\s*\<endsw\>'</font><br>
<font color="#008000">~elsewith</font> <strong><font color="#000080">define-submode</font></strong> <em>csh</em> <strong><font color="#000080">group</font></strong> <font color="#800080">'loop'</font><br>
<strong><font color="#000080">fence-if</font></strong> <font color="#800080">'^\s*\<foreach\s\+.*\|while\>\s*(.*)'</font><br>
<strong><font color="#000080">fence-fi</font></strong> <font color="#800080">'^\s*\<end\>'</font><br>
<font color="#008000">~endwith</font><br>
<!--atr2html}}-->
<h3 id="definemajormode-id"><a name="definemajormode">The "define-majormode" command</a></h3>
<p>
This takes a single argument, a majormode name. To follow existing
convention, the string "mode" is automatically appended to the given
name. Associated modes are defined or modified with the define-submode
command. Vile maintains a list of majormodes. Only one majormode can
be associated with a buffer (none need be associated). After
definition, a majormode can be set or unset just like any other buffer
mode:
<!--{{atr2html--><p style="font-family: monospace;">
<strong><font color="#000080">define-majormode</font></strong> <strong><font color="#000080">c</font></strong><br>
<font color="#800000">; defines "cmode"</font><br>
<br>
<strong><font color="#000080">setl</font></strong> <strong><font color="#000080">cmode</font></strong><br>
<font color="#800000">; sets the mode for the current buffer</font><br>
<br>
<strong><font color="#000080">setl</font></strong> <strong><font color="#000080">nocmode</font></strong><br>
<font color="#800000">; clear c mode (existing implementation)</font><br>
<br>
<strong><font color="#000080">unsetl</font></strong> <strong><font color="#000080">cmode</font></strong><br>
<font color="#800000">; clear c mode</font><br>
<!--atr2html}}--></p>
The restriction to a single majormode is because mode values are
internally represented as structures with a pointer. The pointer
denotes which value (currently local or global) is used. The
majormode implementation adds a level to this, e.g.,
<pre>
value -> self (local)
value -> global (global)
value -> major (majormode)
</pre><p>
When a majormode is defined, an array of the existing minor mode values
is allocated, all pointing to the global modes. The define-submode
command modifies these to make them local pointers. When a buffer is
associated with a majormode, all of its buffer mode values are pointed
to the majormode's values. (To keep the bookkeeping straight, modifying
a global buffer mode must also modify the copies of non-local buffer
mode values).
<h3 id="definesubmode-id"><a name="definesubmode">The "define-submode" command</a></h3>
<p>
This command sets local values of buffer modes for the given majormode,
e.g.,
<!--{{atr2html--><p style="font-family: monospace;">
<strong><font color="#000080">define-submode</font></strong> <strong><font color="#000080">c</font></strong> <strong><font color="#000080">autoindent</font></strong><br>
<!--atr2html}}--></p>
The majormode name is required. The names after the majormode name are
names of buffer modes with a corresponding value. Any number of modes
can be specified in a single command, e.g.,
<!--{{atr2html--><p style="font-family: monospace;">
<strong><font color="#000080">define-submode</font></strong> <strong><font color="#000080">c</font></strong> <strong><font color="#000080">autoindent</font></strong> <strong><font color="#000080">tabstop</font></strong><strong><font color="#800000">=</font></strong><strong><font color="#008080">4</font></strong><br>
<!--atr2html}}--></p>
For each mode given, vile defines corresponding names by which they can
be referenced, e.g., "c-autoindent" (from the long mode name
"autoindent") and "cai" (from the short mode name "ai" for autoindent).
The long mode name is always appended with a hyphen, and the short mode
name is appended without a hyphen.
<p>
The term "submode" is used in the command rather than the more natural
"minor mode" to simplify name-completion.
<p>
The following are keywords that aren't minor modes, but are recognized
solely by the define-submode command:
<dl>
<dt>mode-pathname<dd>
The full pathname which is tested to trigger association with a
majormode, e.g., "RCS/*,v".
<dt>mode-filename<dd>
The filename which is tested to trigger association with a
majormode, e.g., "Makefile".
<dt>suffixes<dd>
The filename suffix which is tested to trigger
association with a majormode (e.g., c-suffixes)
Note that since the default value for the c-suffixes mode
is a regular expression that will match some other file
types (C++ files, for instance), if you define a new major
mode for one of those suffixes you may want to reset
c-suffixes to something less inclusive.
<dt>preamble<dd>
Regular expression, matched against the beginning of a
file (the first line) used to trigger association with
a majormode (e.g., "^!#.*\/perl[^a-z]").
<dt>filtername<dd>
A shell command telling which filter to call, and how to do
that. The form of the command is limited, since it is
interpreted for internal calls:
<pre>
{filter} {options}
</pre><p>
where {filter} is the filename for the filter, e.g.,
<pre>
vile-c-filt
</pre><p>
and options include:
<dl>
<dt>-k mode<dd>
The keyword filename, omitting ".keywords".
For instance, the C filter vile-c-filt is used
for C, C++, JavaScript and Java by changing the
keyword file.
<dt>-q<dd>
Quit after loading the keyword definitions.
<dt>-t tabs<dd>
Set the tabstops, used in the imake filter
to check for coincidental matches between a
tab and spaces that are the same number of
columns.
<dt>-v
<dt>-vv<dd>
Debug traces, mainly to show which keyword
files are loaded, and what information is
parsed from them.
</dl><p>
Other options may be implemented that are specific to a filter
program. For instance, vile-c-filt recognizes a -p option to
mark preprocessor lines with an error (used for Java).
<dt>before
<dt>after<dd>
A string that tells vile how to rank the majormode.
Normally vile checks each mode in order by name, but there
are special cases where you may want to check one mode
before another. For example, the C++ majormode cppmode
would be checked after cmode, but that uses suffixes which
are a subset of the built-in cmode's suffixes and would not
be found. So cppmode is qualified before="c".
<dt>group<dd>
followed by a name, defines an alternative set of submode
values.
<p>
Currently used only for complex fences, this could be applied
to simple fences, and (with new flags not yet defined) extend
both styles of fences for indentation and formatting.
<dt>fences<dd>
These are "complex" fences, which are matched one expression
per line. The names are "fence-" followed by any of the
following keywords with a regular expression:
<pre>
if, elif, else, fi
</pre><p>
Vile searches through all groups of complex fences for a
match before trying simple fences.
<dt>comments<dd>
These are "simple" fences, which can be matched any number
of times per line. The pairs need not appear on the same
line. Like complex fences, they have an implied order.
The default values support C-style comments, with the '%' going
between "/*" and "*/". The names use "fence-" followed any of
the following keywords with a regular expression: begin, end.
<dt>indent (not implemented)<dd>
The keyword "cstyle", or any of the following keywords
with a regular expression: begin, end, if, then, else,
elif, endif.
</dl><p>
Other features which should be controlled by majormodes include limiting
the scope of the entab and detab commands.
<h3 id="removemajormode-id"><a name="removemajormode">The "remove-majormode" command</a></h3>
<p>
This command has two forms:
<dl>
<dt>remove-majormode {majormode}<dd>
This removes the definition of the majormode. Buffers
that were associated with the mode revert to no
majormode.
</dl><p>
or
<dl>
<dt>remove-majormode {majormode} {name}<dd>
This removes the value of {name} from {majormode},
leaving it set to the global value, if any.
</dl>
<h3 id="removesubmode-id"><a name="removesubmode">The "remove-submode" command</a></h3>
<p>
Remove the special association of a submode from a majormode.
<h3 id="example2-id"><a name="example2">Example</a></h3>
<p>
The original builtin C/C++ majormode description is equivalent to
<!--{{atr2html--><p style="font-family: monospace;">
<strong><font color="#000080">define-mode</font></strong> <strong><font color="#000080">c</font></strong><br>
<font color="#008000">~with</font> <strong><font color="#000080">define-submode</font></strong> <strong><font color="#000080">c</font></strong><br>
<strong><font color="#000080">suffix</font></strong> <font color="#800080">"\\.\\(\\([Cchisyl]\\)\\|CC\\|cc|cpp\\|cxx\\|hxx\\|scm\\)$"</font><br>
<strong><font color="#000080">comment-prefix</font></strong><strong><font color="#800000">=</font></strong><font color="#800080">"^\\s*\\(\\s*[#*>]\\)\\+"</font><br>
<strong><font color="#000080">comments</font></strong><strong><font color="#800000">=</font></strong><font color="#800080">"^\\s*/\\?\\(\\s*[#*>]\\)\\+/\\?\\s*$"</font><br>
<strong><font color="#000080">fence-begin</font></strong><strong><font color="#800000">=</font></strong><font color="#800080">"/\\*"</font><br>
<strong><font color="#000080">fence-end</font></strong><strong><font color="#800000">=</font></strong><font color="#800080">"\\*/"</font><br>
<strong><font color="#000080">fence-if</font></strong><strong><font color="#800000">=</font></strong><font color="#800080">"^\\s*#\\s*if"</font><br>
<strong><font color="#000080">fence-elif</font></strong><strong><font color="#800000">=</font></strong><font color="#800080">"^\\s*#\\s*elif\\>"</font><br>
<strong><font color="#000080">fence-else</font></strong><strong><font color="#800000">=</font></strong><font color="#800080">"^\\s*#\\s*else\\>"</font><br>
<strong><font color="#000080">fence-fi</font></strong><strong><font color="#800000">=</font></strong><font color="#800080">"^\\s*#\\s*endif\\>"</font><br>
<strong><font color="#000080">cindent</font></strong><br>
<font color="#008000">~endwith</font><br>
<!--atr2html}}--></p>
Note that the following are equivalent once you have defined the majormode "c":
<!--{{atr2html--><p style="font-family: monospace;">
<strong><font color="#000080">set</font></strong> <strong><font color="#000080">cts</font></strong><strong><font color="#800000">=</font></strong><strong><font color="#008080">8</font></strong><br>
<strong><font color="#000080">set</font></strong> <strong><font color="#000080">c-tabstop</font></strong><strong><font color="#800000">=</font></strong><strong><font color="#008080">8</font></strong><br>
<strong><font color="#000080">define-submode</font></strong> <strong><font color="#000080">c</font></strong> <strong><font color="#000080">tabstop</font></strong><strong><font color="#800000">=</font></strong><strong><font color="#008080">8</font></strong><br>
<!--atr2html}}--></p>
<h2 id="credits-id"><a name="credits">Credits</a></h2>
Most of this was written by Thomas Dickey, with fixes from Clark Morgan and
Steven Lembark.
|
