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1 | @c -*-texinfo-*- |
2 | @c This is part of the GNU Emacs Lisp Reference Manual. | |
177c0ea7 | 3 | @c Copyright (C) 1997, 1998, 1999, 2000, 2002 Free Software Foundation, Inc. |
cc6d0d2c RS |
4 | @c See the file elisp.texi for copying conditions. |
5 | @setfilename ../info/customize | |
6 | @node Customization, Loading, Macros, Top | |
7 | @chapter Writing Customization Definitions | |
8 | ||
969fe9b5 RS |
9 | This chapter describes how to declare user options for customization, |
10 | and also customization groups for classifying them. We use the term | |
11 | @dfn{customization item} to include both kinds of customization | |
12 | definitions---as well as face definitions (@pxref{Defining Faces}). | |
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13 | |
14 | @menu | |
15 | * Common Keywords:: | |
177c0ea7 JB |
16 | * Group Definitions:: |
17 | * Variable Definitions:: | |
cc6d0d2c RS |
18 | * Customization Types:: |
19 | @end menu | |
20 | ||
21 | @node Common Keywords | |
8241495d | 22 | @section Common Item Keywords |
cc6d0d2c | 23 | |
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24 | All kinds of customization declarations (for variables and groups, and |
25 | for faces) accept keyword arguments for specifying various information. | |
26 | This section describes some keywords that apply to all kinds. | |
cc6d0d2c | 27 | |
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28 | All of these keywords, except @code{:tag}, can be used more than once |
29 | in a given item. Each use of the keyword has an independent effect. | |
30 | The keyword @code{:tag} is an exception because any given item can only | |
31 | display one name. | |
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32 | |
33 | @table @code | |
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34 | @item :tag @var{label} |
35 | Use @var{label}, a string, instead of the item's name, to label the item | |
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36 | in customization menus and buffers. |
37 | ||
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38 | @item :group @var{group} |
39 | Put this customization item in group @var{group}. When you use | |
40 | @code{:group} in a @code{defgroup}, it makes the new group a subgroup of | |
41 | @var{group}. | |
42 | ||
43 | If you use this keyword more than once, you can put a single item into | |
44 | more than one group. Displaying any of those groups will show this | |
8241495d | 45 | item. Please don't overdo this, since the result would be annoying. |
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46 | |
47 | @item :link @var{link-data} | |
48 | Include an external link after the documentation string for this item. | |
49 | This is a sentence containing an active field which references some | |
50 | other documentation. | |
51 | ||
8f626a4c | 52 | There are four alternatives you can use for @var{link-data}: |
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53 | |
54 | @table @code | |
55 | @item (custom-manual @var{info-node}) | |
56 | Link to an Info node; @var{info-node} is a string which specifies the | |
57 | node name, as in @code{"(emacs)Top"}. The link appears as | |
58 | @samp{[manual]} in the customization buffer. | |
59 | ||
60 | @item (info-link @var{info-node}) | |
61 | Like @code{custom-manual} except that the link appears | |
62 | in the customization buffer with the Info node name. | |
63 | ||
64 | @item (url-link @var{url}) | |
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65 | Link to a web page; @var{url} is a string which specifies the @sc{url}. |
66 | The link appears in the customization buffer as @var{url}. | |
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67 | |
68 | @item (emacs-commentary-link @var{library}) | |
69 | Link to the commentary section of a library; @var{library} is a string | |
70 | which specifies the library name. | |
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71 | @end table |
72 | ||
73 | You can specify the text to use in the customization buffer by adding | |
74 | @code{:tag @var{name}} after the first element of the @var{link-data}; | |
75 | for example, @code{(info-link :tag "foo" "(emacs)Top")} makes a link to | |
76 | the Emacs manual which appears in the buffer as @samp{foo}. | |
77 | ||
78 | An item can have more than one external link; however, most items have | |
79 | none at all. | |
80 | ||
81 | @item :load @var{file} | |
82 | Load file @var{file} (a string) before displaying this customization | |
83 | item. Loading is done with @code{load-library}, and only if the file is | |
84 | not already loaded. | |
85 | ||
86 | @item :require @var{feature} | |
87 | Require feature @var{feature} (a symbol) when installing a value for | |
88 | this item (an option or a face) that was saved using the customization | |
89 | feature. This is done by calling @code{require}. | |
90 | ||
91 | The most common reason to use @code{:require} is when a variable enables | |
92 | a feature such as a minor mode, and just setting the variable won't have | |
93 | any effect unless the code which implements the mode is loaded. | |
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94 | @end table |
95 | ||
96 | @node Group Definitions | |
97 | @section Defining Custom Groups | |
98 | ||
969fe9b5 | 99 | Each Emacs Lisp package should have one main customization group which |
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100 | contains all the options, faces and other groups in the package. If the |
101 | package has a small number of options and faces, use just one group and | |
102 | put everything in it. When there are more than twelve or so options and | |
103 | faces, then you should structure them into subgroups, and put the | |
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104 | subgroups under the package's main customization group. It is OK to |
105 | put some of the options and faces in the package's main group alongside | |
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106 | the subgroups. |
107 | ||
969fe9b5 RS |
108 | The package's main or only group should be a member of one or more of |
109 | the standard customization groups. (To display the full list of them, | |
110 | use @kbd{M-x customize}.) Choose one or more of them (but not too | |
111 | many), and add your group to each of them using the @code{:group} | |
112 | keyword. | |
cc6d0d2c | 113 | |
969fe9b5 | 114 | The way to declare new customization groups is with @code{defgroup}. |
cc6d0d2c | 115 | |
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116 | @defmac defgroup group members doc [keyword value]... |
117 | Declare @var{group} as a customization group containing @var{members}. | |
118 | Do not quote the symbol @var{group}. The argument @var{doc} specifies | |
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119 | the documentation string for the group. It should not start with a |
120 | @samp{*} as in @code{defcustom}; that convention is for variables only. | |
cc6d0d2c | 121 | |
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122 | The argument @var{members} is a list specifying an initial set of |
123 | customization items to be members of the group. However, most often | |
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124 | @var{members} is @code{nil}, and you specify the group's members by |
125 | using the @code{:group} keyword when defining those members. | |
cc6d0d2c | 126 | |
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127 | If you want to specify group members through @var{members}, each element |
128 | should have the form @code{(@var{name} @var{widget})}. Here @var{name} | |
129 | is a symbol, and @var{widget} is a widget type for editing that symbol. | |
130 | Useful widgets are @code{custom-variable} for a variable, | |
131 | @code{custom-face} for a face, and @code{custom-group} for a group. | |
cc6d0d2c | 132 | |
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133 | When a new group is introduced into Emacs, use this keyword in |
134 | @code{defgroup}: | |
135 | ||
136 | @table @code | |
137 | @item :version @var{version} | |
138 | This option specifies that the group was first introduced in Emacs | |
139 | version @var{version}. The value @var{version} must be a string. | |
140 | @end table | |
141 | ||
142 | Tag the group with a version like this when it is introduced, rather | |
143 | than the individual members (@pxref{Variable Definitions}). | |
144 | ||
cc6d0d2c | 145 | In addition to the common keywords (@pxref{Common Keywords}), you can |
3d66f910 | 146 | also use this keyword in @code{defgroup}: |
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147 | |
148 | @table @code | |
149 | @item :prefix @var{prefix} | |
150 | If the name of an item in the group starts with @var{prefix}, then the | |
151 | tag for that item is constructed (by default) by omitting @var{prefix}. | |
152 | ||
153 | One group can have any number of prefixes. | |
154 | @end table | |
155 | @end defmac | |
156 | ||
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157 | The prefix-discarding feature is currently turned off, which means |
158 | that @code{:prefix} currently has no effect. We did this because we | |
159 | found that discarding the specified prefixes often led to confusing | |
160 | names for options. This happened because the people who wrote the | |
161 | @code{defgroup} definitions for various groups added @code{:prefix} | |
162 | keywords whenever they make logical sense---that is, whenever the | |
163 | variables in the library have a common prefix. | |
164 | ||
165 | In order to obtain good results with @code{:prefix}, it would be | |
166 | necessary to check the specific effects of discarding a particular | |
167 | prefix, given the specific items in a group and their names and | |
168 | documentation. If the resulting text is not clear, then @code{:prefix} | |
169 | should not be used in that case. | |
170 | ||
171 | It should be possible to recheck all the customization groups, delete | |
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172 | the @code{:prefix} specifications which give unclear results, and then |
173 | turn this feature back on, if someone would like to do the work. | |
174 | ||
175 | @node Variable Definitions | |
176 | @section Defining Customization Variables | |
177 | ||
969fe9b5 | 178 | Use @code{defcustom} to declare user-editable variables. |
cc6d0d2c | 179 | |
4577e8cc | 180 | @defmac defcustom option default doc [keyword value]@dots{} |
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181 | Declare @var{option} as a customizable user option variable. Do not |
182 | quote @var{option}. The argument @var{doc} specifies the documentation | |
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183 | string for the variable. It should often start with a @samp{*} to mark |
184 | it as a @dfn{user option} (@pxref{Defining Variables}). Do not start | |
185 | the documentation string with @samp{*} for options which cannot or | |
186 | normally should not be set with @code{set-variable}; examples of the | |
187 | former are global minor mode options such as | |
188 | @code{global-font-lock-mode} and examples of the latter are hooks. | |
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189 | |
190 | If @var{option} is void, @code{defcustom} initializes it to | |
191 | @var{default}. @var{default} should be an expression to compute the | |
a9f0a989 | 192 | value; be careful in writing it, because it can be evaluated on more |
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193 | than one occasion. You should normally avoid using backquotes in |
194 | @var{default} because they are not expanded when editing the value, | |
195 | causing list values to appear to have the wrong structure. | |
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196 | |
197 | When you evaluate a @code{defcustom} form with @kbd{C-M-x} in Emacs Lisp | |
198 | mode (@code{eval-defun}), a special feature of @code{eval-defun} | |
199 | arranges to set the variable unconditionally, without testing whether | |
200 | its value is void. (The same feature applies to @code{defvar}.) | |
201 | @xref{Defining Variables}. | |
7dd3d99f | 202 | @end defmac |
cc6d0d2c | 203 | |
7dd3d99f | 204 | @code{defcustom} accepts the following additional keywords: |
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205 | |
206 | @table @code | |
207 | @item :type @var{type} | |
208 | Use @var{type} as the data type for this option. It specifies which | |
209 | values are legitimate, and how to display the value. | |
210 | @xref{Customization Types}, for more information. | |
211 | ||
212 | @item :options @var{list} | |
213 | Specify @var{list} as the list of reasonable values for use in this | |
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214 | option. The user is not restricted to using only these values, but they |
215 | are offered as convenient alternatives. | |
cc6d0d2c | 216 | |
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217 | This is meaningful only for certain types, currently including |
218 | @code{hook}, @code{plist} and @code{alist}. See the definition of the | |
219 | individual types for a description of how to use @code{:options}. | |
cc6d0d2c RS |
220 | |
221 | @item :version @var{version} | |
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222 | This option specifies that the variable was first introduced, or its |
223 | default value was changed, in Emacs version @var{version}. The value | |
224 | @var{version} must be a string. For example, | |
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225 | |
226 | @example | |
227 | (defcustom foo-max 34 | |
228 | "*Maximum number of foo's allowed." | |
229 | :type 'integer | |
230 | :group 'foo | |
231 | :version "20.3") | |
232 | @end example | |
233 | ||
234 | @item :set @var{setfunction} | |
235 | Specify @var{setfunction} as the way to change the value of this option. | |
236 | The function @var{setfunction} should take two arguments, a symbol and | |
237 | the new value, and should do whatever is necessary to update the value | |
238 | properly for this option (which may not mean simply setting the option | |
239 | as a Lisp variable). The default for @var{setfunction} is | |
240 | @code{set-default}. | |
241 | ||
242 | @item :get @var{getfunction} | |
243 | Specify @var{getfunction} as the way to extract the value of this | |
244 | option. The function @var{getfunction} should take one argument, a | |
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245 | symbol, and should return whatever customize should use as the |
246 | ``current value'' for that symbol (which need not be the symbol's Lisp | |
247 | value). The default is @code{default-value}. | |
248 | ||
249 | You have to really understand the workings of Custom to use | |
250 | @code{:get} correctly. It is meant for values that are treated in | |
251 | Custom as variables but are not actually stored in Lisp variables. It | |
252 | is almost surely a mistake to specify @code{getfunction} for a value | |
253 | that really is stored in a Lisp variable. | |
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254 | |
255 | @item :initialize @var{function} | |
256 | @var{function} should be a function used to initialize the variable when | |
257 | the @code{defcustom} is evaluated. It should take two arguments, the | |
258 | symbol and value. Here are some predefined functions meant for use in | |
259 | this way: | |
260 | ||
261 | @table @code | |
262 | @item custom-initialize-set | |
969fe9b5 | 263 | Use the variable's @code{:set} function to initialize the variable, but |
7db0894f | 264 | do not reinitialize it if it is already non-void. |
cc6d0d2c RS |
265 | |
266 | @item custom-initialize-default | |
969fe9b5 RS |
267 | Like @code{custom-initialize-set}, but use the function |
268 | @code{set-default} to set the variable, instead of the variable's | |
269 | @code{:set} function. This is the usual choice for a variable whose | |
270 | @code{:set} function enables or disables a minor mode; with this choice, | |
271 | defining the variable will not call the minor mode function, but | |
272 | customizing the variable will do so. | |
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273 | |
274 | @item custom-initialize-reset | |
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275 | Always use the @code{:set} function to initialize the variable. If |
276 | the variable is already non-void, reset it by calling the @code{:set} | |
969fe9b5 | 277 | function using the current value (returned by the @code{:get} method). |
7db0894f | 278 | This is the default @code{:initialize} function. |
cc6d0d2c RS |
279 | |
280 | @item custom-initialize-changed | |
969fe9b5 RS |
281 | Use the @code{:set} function to initialize the variable, if it is |
282 | already set or has been customized; otherwise, just use | |
283 | @code{set-default}. | |
cc6d0d2c | 284 | @end table |
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285 | |
286 | @item :set-after @var{variables} | |
287 | When setting variables according to saved customizations, make sure to | |
288 | set the variables @var{variables} before this one; in other words, delay | |
289 | setting this variable until after those others have been handled. Use | |
290 | @code{:set-after} if setting this variable won't work properly unless | |
291 | those other variables already have their intended values. | |
969fe9b5 | 292 | @end table |
cc6d0d2c | 293 | |
969fe9b5 | 294 | The @code{:require} option is useful for an option that turns on the |
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295 | operation of a certain feature. Assuming that the package is coded to |
296 | check the value of the option, you still need to arrange for the package | |
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297 | to be loaded. You can do that with @code{:require}. @xref{Common |
298 | Keywords}. Here is an example, from the library @file{paren.el}: | |
299 | ||
300 | @example | |
301 | (defcustom show-paren-mode nil | |
29b677db | 302 | "Toggle Show Paren mode..." |
969fe9b5 | 303 | :set (lambda (symbol value) |
a9f0a989 | 304 | (show-paren-mode (or value 0))) |
969fe9b5 RS |
305 | :initialize 'custom-initialize-default |
306 | :type 'boolean | |
307 | :group 'paren-showing | |
308 | :require 'paren) | |
309 | @end example | |
cc6d0d2c | 310 | |
b6954afd RS |
311 | If a customization item has a type such as @code{hook} or @code{alist}, |
312 | which supports @code{:options}, you can add additional options to the | |
313 | item, outside the @code{defcustom} declaration, by calling | |
314 | @code{custom-add-option}. For example, if you define a function | |
315 | @code{my-lisp-mode-initialization} intended to be called from | |
316 | @code{emacs-lisp-mode-hook}, you might want to add that to the list of | |
317 | options for @code{emacs-lisp-mode-hook}, but not by editing its | |
318 | definition. You can do it thus: | |
319 | ||
320 | @example | |
8241495d RS |
321 | (custom-add-option 'emacs-lisp-mode-hook |
322 | 'my-lisp-mode-initialization) | |
b6954afd | 323 | @end example |
cc6d0d2c RS |
324 | |
325 | @defun custom-add-option symbol option | |
b6954afd | 326 | To the customization @var{symbol}, add @var{option}. |
cc6d0d2c | 327 | |
b6954afd RS |
328 | The precise effect of adding @var{option} depends on the customization |
329 | type of @var{symbol}. | |
cc6d0d2c | 330 | @end defun |
cc6d0d2c RS |
331 | |
332 | Internally, @code{defcustom} uses the symbol property | |
333 | @code{standard-value} to record the expression for the default value, | |
334 | and @code{saved-value} to record the value saved by the user with the | |
335 | customization buffer. The @code{saved-value} property is actually a | |
336 | list whose car is an expression which evaluates to the value. | |
337 | ||
cc6d0d2c RS |
338 | @node Customization Types |
339 | @section Customization Types | |
340 | ||
341 | When you define a user option with @code{defcustom}, you must specify | |
969fe9b5 | 342 | its @dfn{customization type}. That is a Lisp object which describes (1) |
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343 | which values are legitimate and (2) how to display the value in the |
344 | customization buffer for editing. | |
345 | ||
346 | You specify the customization type in @code{defcustom} with the | |
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347 | @code{:type} keyword. The argument of @code{:type} is evaluated, but |
348 | only once when the @code{defcustom} is executed, so it isn't useful | |
349 | for the value to vary. Normally we use a quoted constant. For | |
350 | example: | |
cc6d0d2c RS |
351 | |
352 | @example | |
353 | (defcustom diff-command "diff" | |
354 | "*The command to use to run diff." | |
969fe9b5 | 355 | :type '(string) |
cc6d0d2c RS |
356 | :group 'diff) |
357 | @end example | |
358 | ||
969fe9b5 RS |
359 | In general, a customization type is a list whose first element is a |
360 | symbol, one of the customization type names defined in the following | |
361 | sections. After this symbol come a number of arguments, depending on | |
362 | the symbol. Between the type symbol and its arguments, you can | |
363 | optionally write keyword-value pairs (@pxref{Type Keywords}). | |
cc6d0d2c | 364 | |
969fe9b5 RS |
365 | Some of the type symbols do not use any arguments; those are called |
366 | @dfn{simple types}. For a simple type, if you do not use any | |
367 | keyword-value pairs, you can omit the parentheses around the type | |
368 | symbol. For example just @code{string} as a customization type is | |
369 | equivalent to @code{(string)}. | |
cc6d0d2c RS |
370 | |
371 | @menu | |
372 | * Simple Types:: | |
373 | * Composite Types:: | |
374 | * Splicing into Lists:: | |
375 | * Type Keywords:: | |
376 | @end menu | |
377 | ||
c5c36e02 | 378 | All customization types are implemented as widgets; see @ref{Top, , |
333c5fc5 | 379 | Introduction, widget, The Emacs Widget Library}, for details. |
c5c36e02 | 380 | |
cc6d0d2c RS |
381 | @node Simple Types |
382 | @subsection Simple Types | |
383 | ||
384 | This section describes all the simple customization types. | |
385 | ||
386 | @table @code | |
387 | @item sexp | |
388 | The value may be any Lisp object that can be printed and read back. You | |
389 | can use @code{sexp} as a fall-back for any option, if you don't want to | |
390 | take the time to work out a more specific type to use. | |
391 | ||
392 | @item integer | |
393 | The value must be an integer, and is represented textually | |
394 | in the customization buffer. | |
395 | ||
396 | @item number | |
177f790c MR |
397 | The value must be a number (floating point or integer), and is |
398 | represented textually in the customization buffer. | |
399 | ||
400 | @item float | |
401 | The value must be a floating point number, and is represented | |
402 | textually in the customization buffer. | |
cc6d0d2c RS |
403 | |
404 | @item string | |
405 | The value must be a string, and the customization buffer shows just the | |
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406 | contents, with no delimiting @samp{"} characters and no quoting with |
407 | @samp{\}. | |
cc6d0d2c RS |
408 | |
409 | @item regexp | |
969fe9b5 RS |
410 | Like @code{string} except that the string must be a valid regular |
411 | expression. | |
cc6d0d2c RS |
412 | |
413 | @item character | |
414 | The value must be a character code. A character code is actually an | |
415 | integer, but this type shows the value by inserting the character in the | |
416 | buffer, rather than by showing the number. | |
417 | ||
418 | @item file | |
419 | The value must be a file name, and you can do completion with | |
420 | @kbd{M-@key{TAB}}. | |
421 | ||
422 | @item (file :must-match t) | |
423 | The value must be a file name for an existing file, and you can do | |
424 | completion with @kbd{M-@key{TAB}}. | |
425 | ||
426 | @item directory | |
427 | The value must be a directory name, and you can do completion with | |
428 | @kbd{M-@key{TAB}}. | |
429 | ||
a9f0a989 RS |
430 | @item hook |
431 | The value must be a list of functions (or a single function, but that is | |
432 | obsolete usage). This customization type is used for hook variables. | |
1911e6e5 RS |
433 | You can use the @code{:options} keyword in a hook variable's |
434 | @code{defcustom} to specify a list of functions recommended for use in | |
435 | the hook; see @ref{Variable Definitions}. | |
a9f0a989 | 436 | |
b6954afd | 437 | @item alist |
08f0f5e9 KH |
438 | The value must be a list of cons-cells, the @sc{car} of each cell |
439 | representing a key, and the @sc{cdr} of the same cell representing an | |
440 | associated value. The user can add and delete key/value pairs, and | |
b6954afd RS |
441 | edit both the key and the value of each pair. |
442 | ||
443 | You can specify the key and value types like this: | |
444 | ||
8241495d RS |
445 | @smallexample |
446 | (alist :key-type @var{key-type} :value-type @var{value-type}) | |
447 | @end smallexample | |
b6954afd RS |
448 | |
449 | @noindent | |
450 | where @var{key-type} and @var{value-type} are customization type | |
451 | specifications. The default key type is @code{sexp}, and the default | |
452 | value type is @code{sexp}. | |
453 | ||
454 | The user can add any key matching the specified key type, but you can | |
455 | give some keys a preferential treatment by specifying them with the | |
456 | @code{:options} (see @ref{Variable Definitions}). The specified keys | |
457 | will always be shown in the customize buffer (together with a suitable | |
458 | value), with a checkbox to include or exclude or disable the key/value | |
459 | pair from the alist. The user will not be able to edit the keys | |
460 | specified by the @code{:options} keyword argument. | |
461 | ||
462 | The argument to the @code{:options} keywords should be a list of option | |
463 | specifications. Ordinarily, the options are simply atoms, which are the | |
464 | specified keys. For example: | |
465 | ||
8241495d | 466 | @smallexample |
b6954afd | 467 | :options '("foo" "bar" "baz") |
8241495d | 468 | @end smallexample |
b6954afd RS |
469 | |
470 | @noindent | |
471 | specifies that there are three ``known'' keys, namely @code{"foo"}, | |
472 | @code{"bar"} and @code{"baz"}, which will always be shown first. | |
473 | ||
474 | You may want to restrict the value type for specific keys, for example, | |
475 | the value associated with the @code{"bar"} key can only be an integer. | |
476 | You can specify this by using a list instead of an atom in the option | |
477 | specification. The first element will specify the key, like before, | |
478 | while the second element will specify the value type. | |
479 | ||
8241495d | 480 | @smallexample |
b6954afd | 481 | :options '("foo" ("bar" integer) "baz") |
8241495d | 482 | @end smallexample |
b6954afd RS |
483 | |
484 | Finally, you may want to change how the key is presented. By default, | |
485 | the key is simply shown as a @code{const}, since the user cannot change | |
486 | the special keys specified with the @code{:options} keyword. However, | |
487 | you may want to use a more specialized type for presenting the key, like | |
488 | @code{function-item} if you know it is a symbol with a function binding. | |
489 | This is done by using a customization type specification instead of a | |
490 | symbol for the key. | |
491 | ||
8241495d | 492 | @smallexample |
b6954afd | 493 | :options '("foo" ((function-item some-function) integer) "baz") |
8241495d | 494 | @end smallexample |
b6954afd | 495 | |
08f0f5e9 | 496 | Many alists use lists with two elements, instead of cons cells. For |
b6954afd RS |
497 | example, |
498 | ||
8241495d | 499 | @smallexample |
b6954afd RS |
500 | (defcustom list-alist '(("foo" 1) ("bar" 2) ("baz" 3)) |
501 | "Each element is a list of the form (KEY VALUE).") | |
8241495d | 502 | @end smallexample |
b6954afd RS |
503 | |
504 | @noindent | |
177c0ea7 | 505 | instead of |
b6954afd | 506 | |
8241495d | 507 | @smallexample |
b6954afd RS |
508 | (defcustom cons-alist '(("foo" . 1) ("bar" . 2) ("baz" . 3)) |
509 | "Each element is a cons-cell (KEY . VALUE).") | |
8241495d | 510 | @end smallexample |
b6954afd RS |
511 | |
512 | Because of the way lists are implemented on top of cons cells, you can | |
513 | treat @code{list-alist} in the example above as a cons cell alist, where | |
514 | the value type is a list with a single element containing the real | |
515 | value. | |
516 | ||
8241495d | 517 | @smallexample |
b6954afd RS |
518 | (defcustom list-alist '(("foo" 1) ("bar" 2) ("baz" 3)) |
519 | "Each element is a list of the form (KEY VALUE)." | |
520 | :type '(alist :value-type (group integer))) | |
8241495d | 521 | @end smallexample |
b6954afd RS |
522 | |
523 | The @code{group} widget is used here instead of @code{list} only because | |
524 | the formatting is better suited for the purpose. | |
525 | ||
526 | Similarily, you can have alists with more values associated with each | |
527 | key, using variations of this trick: | |
528 | ||
8241495d | 529 | @smallexample |
177c0ea7 | 530 | (defcustom person-data '(("brian" 50 t) |
b6954afd RS |
531 | ("dorith" 55 nil) |
532 | ("ken" 52 t)) | |
3d3df9e1 RS |
533 | "Alist of basic info about people. |
534 | Each element has the form (NAME AGE MALE-FLAG)." | |
b6954afd RS |
535 | :type '(alist :value-type (group age boolean))) |
536 | ||
177c0ea7 | 537 | (defcustom pets '(("brian") |
b6954afd RS |
538 | ("dorith" "dog" "guppy") |
539 | ("ken" "cat")) | |
3d3df9e1 RS |
540 | "Alist of people's pets. |
541 | In an element (KEY . VALUE), KEY is the person's name, | |
542 | and the VALUE is a list of that person's pets." | |
b6954afd | 543 | :type '(alist :value-type (repeat string))) |
8241495d | 544 | @end smallexample |
b6954afd RS |
545 | |
546 | @item plist | |
547 | The @code{plist} custom type is similar to the @code{alist} (see above), | |
548 | except that the information is stored as a property list, i.e. a list of | |
549 | this form: | |
550 | ||
8241495d | 551 | @smallexample |
b6954afd | 552 | (@var{key} @var{value} @var{key} @var{value} @var{key} @var{value} @dots{}) |
8241495d | 553 | @end smallexample |
b6954afd RS |
554 | |
555 | The default @code{:key-type} for @code{plist} is @code{symbol}, | |
556 | rather than @code{sexp}. | |
557 | ||
cc6d0d2c RS |
558 | @item symbol |
559 | The value must be a symbol. It appears in the customization buffer as | |
560 | the name of the symbol. | |
561 | ||
562 | @item function | |
563 | The value must be either a lambda expression or a function name. When | |
564 | it is a function name, you can do completion with @kbd{M-@key{TAB}}. | |
565 | ||
566 | @item variable | |
567 | The value must be a variable name, and you can do completion with | |
568 | @kbd{M-@key{TAB}}. | |
569 | ||
a9f0a989 RS |
570 | @item face |
571 | The value must be a symbol which is a face name, and you can do | |
572 | completion with @kbd{M-@key{TAB}}. | |
573 | ||
cc6d0d2c | 574 | @item boolean |
969fe9b5 RS |
575 | The value is boolean---either @code{nil} or @code{t}. Note that by |
576 | using @code{choice} and @code{const} together (see the next section), | |
577 | you can specify that the value must be @code{nil} or @code{t}, but also | |
578 | specify the text to describe each value in a way that fits the specific | |
579 | meaning of the alternative. | |
5e0c8a23 DL |
580 | |
581 | @item coding-system | |
582 | The value must be a coding-system name, and you can do completion with | |
583 | @kbd{M-@key{TAB}}. | |
584 | ||
585 | @item color | |
586 | The value must be a valid color name, and you can do completion with | |
587 | @kbd{M-@key{TAB}}. A sample is provided, | |
cc6d0d2c RS |
588 | @end table |
589 | ||
590 | @node Composite Types | |
591 | @subsection Composite Types | |
608dc417 | 592 | @cindex arguments (of composite type) |
cc6d0d2c RS |
593 | |
594 | When none of the simple types is appropriate, you can use composite | |
608dc417 RS |
595 | types, which build new types from other types or from specified data. |
596 | The specified types or data are called the @dfn{arguments} of the | |
597 | composite type. The composite type normally looks like this: | |
cc6d0d2c RS |
598 | |
599 | @example | |
608dc417 | 600 | (@var{constructor} @var{arguments}@dots{}) |
cc6d0d2c RS |
601 | @end example |
602 | ||
603 | @noindent | |
608dc417 RS |
604 | but you can also add keyword-value pairs before the arguments, like |
605 | this: | |
cc6d0d2c | 606 | |
608dc417 RS |
607 | @example |
608 | (@var{constructor} @r{@{}@var{keyword} @var{value}@r{@}}@dots{} @var{arguments}@dots{}) | |
609 | @end example | |
cc6d0d2c | 610 | |
608dc417 RS |
611 | Here is a table of constructors and how to use them to write |
612 | composite types: | |
613 | ||
614 | @table @code | |
cc6d0d2c RS |
615 | @item (cons @var{car-type} @var{cdr-type}) |
616 | The value must be a cons cell, its @sc{car} must fit @var{car-type}, and | |
a9f0a989 | 617 | its @sc{cdr} must fit @var{cdr-type}. For example, @code{(cons string |
cc6d0d2c RS |
618 | symbol)} is a customization type which matches values such as |
619 | @code{("foo" . foo)}. | |
620 | ||
969fe9b5 | 621 | In the customization buffer, the @sc{car} and the @sc{cdr} are |
cc6d0d2c RS |
622 | displayed and edited separately, each according to the type |
623 | that you specify for it. | |
624 | ||
625 | @item (list @var{element-types}@dots{}) | |
626 | The value must be a list with exactly as many elements as the | |
627 | @var{element-types} you have specified; and each element must fit the | |
628 | corresponding @var{element-type}. | |
629 | ||
630 | For example, @code{(list integer string function)} describes a list of | |
631 | three elements; the first element must be an integer, the second a | |
632 | string, and the third a function. | |
633 | ||
a9f0a989 | 634 | In the customization buffer, each element is displayed and edited |
cc6d0d2c RS |
635 | separately, according to the type specified for it. |
636 | ||
637 | @item (vector @var{element-types}@dots{}) | |
638 | Like @code{list} except that the value must be a vector instead of a | |
639 | list. The elements work the same as in @code{list}. | |
640 | ||
4577e8cc | 641 | @item (choice @var{alternative-types}@dots{}) |
cc6d0d2c RS |
642 | The value must fit at least one of @var{alternative-types}. |
643 | For example, @code{(choice integer string)} allows either an | |
644 | integer or a string. | |
645 | ||
646 | In the customization buffer, the user selects one of the alternatives | |
647 | using a menu, and can then edit the value in the usual way for that | |
648 | alternative. | |
649 | ||
650 | Normally the strings in this menu are determined automatically from the | |
651 | choices; however, you can specify different strings for the menu by | |
652 | including the @code{:tag} keyword in the alternatives. For example, if | |
653 | an integer stands for a number of spaces, while a string is text to use | |
654 | verbatim, you might write the customization type this way, | |
655 | ||
a9f0a989 | 656 | @example |
cc6d0d2c RS |
657 | (choice (integer :tag "Number of spaces") |
658 | (string :tag "Literal text")) | |
a9f0a989 | 659 | @end example |
cc6d0d2c RS |
660 | |
661 | @noindent | |
662 | so that the menu offers @samp{Number of spaces} and @samp{Literal Text}. | |
663 | ||
969fe9b5 RS |
664 | In any alternative for which @code{nil} is not a valid value, other than |
665 | a @code{const}, you should specify a valid default for that alternative | |
666 | using the @code{:value} keyword. @xref{Type Keywords}. | |
667 | ||
b56f98ab RS |
668 | If some values are covered by more than one of the alternatives, |
669 | customize will choose the first alternative that the value fits. This | |
670 | means you should always list the most specific types first, and the | |
671 | most general last. Here's an example of proper usage: | |
672 | ||
673 | @example | |
674 | (choice (const :tag "Off" nil) symbol (sexp :tag "Other")) | |
675 | @end example | |
676 | ||
677 | @noindent | |
678 | This way, the special value @code{nil} is not treated like other | |
679 | symbols, and symbols are not treated like other Lisp expressions. | |
680 | ||
4577e8cc DL |
681 | @item (radio @var{element-types}@dots{}) |
682 | This is similar to @code{choice}, except that the choices are displayed | |
683 | using `radio buttons' rather than a menu. This has the advantage of | |
684 | displaying documentation for the choices when applicable and so is often | |
685 | a good choice for a choice between constant functions | |
686 | (@code{function-item} customization types). | |
687 | ||
cc6d0d2c RS |
688 | @item (const @var{value}) |
689 | The value must be @var{value}---nothing else is allowed. | |
690 | ||
691 | The main use of @code{const} is inside of @code{choice}. For example, | |
692 | @code{(choice integer (const nil))} allows either an integer or | |
969fe9b5 RS |
693 | @code{nil}. |
694 | ||
695 | @code{:tag} is often used with @code{const}, inside of @code{choice}. | |
696 | For example, | |
697 | ||
a9f0a989 | 698 | @example |
969fe9b5 RS |
699 | (choice (const :tag "Yes" t) |
700 | (const :tag "No" nil) | |
701 | (const :tag "Ask" foo)) | |
a9f0a989 | 702 | @end example |
cc6d0d2c | 703 | |
da03dc1d RS |
704 | @noindent |
705 | describes a variable for which @code{t} means yes, @code{nil} means no, | |
706 | and @code{foo} means ``ask.'' | |
707 | ||
708 | @item (other @var{value}) | |
709 | This alternative can match any Lisp value, but if the user chooses this | |
710 | alternative, that selects the value @var{value}. | |
711 | ||
712 | The main use of @code{other} is as the last element of @code{choice}. | |
713 | For example, | |
714 | ||
715 | @example | |
716 | (choice (const :tag "Yes" t) | |
717 | (const :tag "No" nil) | |
718 | (other :tag "Ask" foo)) | |
719 | @end example | |
720 | ||
721 | @noindent | |
722 | describes a variable for which @code{t} means yes, @code{nil} means no, | |
723 | and anything else means ``ask.'' If the user chooses @samp{Ask} from | |
724 | the menu of alternatives, that specifies the value @code{foo}; but any | |
725 | other value (not @code{t}, @code{nil} or @code{foo}) displays as | |
726 | @samp{Ask}, just like @code{foo}. | |
727 | ||
cc6d0d2c RS |
728 | @item (function-item @var{function}) |
729 | Like @code{const}, but used for values which are functions. This | |
969fe9b5 RS |
730 | displays the documentation string as well as the function name. |
731 | The documentation string is either the one you specify with | |
732 | @code{:doc}, or @var{function}'s own documentation string. | |
cc6d0d2c RS |
733 | |
734 | @item (variable-item @var{variable}) | |
735 | Like @code{const}, but used for values which are variable names. This | |
969fe9b5 RS |
736 | displays the documentation string as well as the variable name. The |
737 | documentation string is either the one you specify with @code{:doc}, or | |
738 | @var{variable}'s own documentation string. | |
cc6d0d2c | 739 | |
1f447a50 KH |
740 | @item (set @var{types}@dots{}) |
741 | The value must be a list, and each element of the list must match one of | |
742 | the @var{types} specified. | |
743 | ||
744 | This appears in the customization buffer as a checklist, so that each of | |
745 | @var{types} may have either one corresponding element or none. It is | |
746 | not possible to specify two different elements that match the same one | |
747 | of @var{types}. For example, @code{(set integer symbol)} allows one | |
748 | integer and/or one symbol in the list; it does not allow multiple | |
749 | integers or multiple symbols. As a result, it is rare to use | |
750 | nonspecific types such as @code{integer} in a @code{set}. | |
751 | ||
752 | Most often, the @var{types} in a @code{set} are @code{const} types, as | |
753 | shown here: | |
754 | ||
755 | @example | |
756 | (set (const :bold) (const :italic)) | |
757 | @end example | |
758 | ||
759 | Sometimes they describe possible elements in an alist: | |
760 | ||
761 | @example | |
762 | (set (cons :tag "Height" (const height) integer) | |
763 | (cons :tag "Width" (const width) integer)) | |
764 | @end example | |
765 | ||
766 | @noindent | |
767 | That lets the user specify a height value optionally | |
768 | and a width value optionally. | |
cc6d0d2c RS |
769 | |
770 | @item (repeat @var{element-type}) | |
771 | The value must be a list and each element of the list must fit the type | |
772 | @var{element-type}. This appears in the customization buffer as a | |
773 | list of elements, with @samp{[INS]} and @samp{[DEL]} buttons for adding | |
774 | more elements or removing elements. | |
608dc417 RS |
775 | |
776 | @item (restricted-sexp :match-alternatives @var{criteria}) | |
777 | This is the most general composite type construct. The value may be | |
778 | any Lisp object that satisfies one of @var{criteria}. @var{criteria} | |
779 | should be a list, and each element should be one of these | |
780 | possibilities: | |
781 | ||
782 | @itemize @bullet | |
783 | @item | |
784 | A predicate---that is, a function of one argument that has no side | |
785 | effects, and returns either @code{nil} or non-@code{nil} according to | |
786 | the argument. Using a predicate in the list says that objects for which | |
787 | the predicate returns non-@code{nil} are acceptable. | |
788 | ||
789 | @item | |
790 | A quoted constant---that is, @code{'@var{object}}. This sort of element | |
791 | in the list says that @var{object} itself is an acceptable value. | |
792 | @end itemize | |
793 | ||
794 | For example, | |
795 | ||
796 | @example | |
797 | (restricted-sexp :match-alternatives | |
798 | (integerp 't 'nil)) | |
799 | @end example | |
800 | ||
801 | @noindent | |
802 | allows integers, @code{t} and @code{nil} as legitimate values. | |
803 | ||
804 | The customization buffer shows all legitimate values using their read | |
805 | syntax, and the user edits them textually. | |
806 | @end table | |
807 | ||
808 | Here is a table of the keywords you can use in keyword-value pairs | |
809 | in a composite type: | |
810 | ||
811 | @table @code | |
812 | @item :tag @var{tag} | |
813 | Use @var{tag} as the name of this alternative, for user communication | |
814 | purposes. This is useful for a type that appears inside of a | |
815 | @code{choice}. | |
816 | ||
817 | @item :match-alternatives @var{criteria} | |
818 | Use @var{criteria} to match possible values. This is used only in | |
819 | @code{restricted-sexp}. | |
820 | ||
821 | @item :args @var{argumentlist} | |
822 | Use the elements of @var{argumentlist} as the arguments of the type | |
823 | construct. For instance, @code{(const :args (foo))} is equivalent to | |
824 | @code{(const foo)}. You rarely need to write @code{:args} explicitly, | |
825 | because normally the arguments are recognized automatically as | |
826 | whatever follows the last keyword-value pair. | |
cc6d0d2c RS |
827 | @end table |
828 | ||
829 | @node Splicing into Lists | |
830 | @subsection Splicing into Lists | |
831 | ||
832 | The @code{:inline} feature lets you splice a variable number of | |
833 | elements into the middle of a list or vector. You use it in a | |
834 | @code{set}, @code{choice} or @code{repeat} type which appears among the | |
835 | element-types of a @code{list} or @code{vector}. | |
836 | ||
837 | Normally, each of the element-types in a @code{list} or @code{vector} | |
838 | describes one and only one element of the list or vector. Thus, if an | |
839 | element-type is a @code{repeat}, that specifies a list of unspecified | |
840 | length which appears as one element. | |
841 | ||
842 | But when the element-type uses @code{:inline}, the value it matches is | |
843 | merged directly into the containing sequence. For example, if it | |
844 | matches a list with three elements, those become three elements of the | |
845 | overall sequence. This is analogous to using @samp{,@@} in the backquote | |
846 | construct. | |
847 | ||
241f79af | 848 | For example, to specify a list whose first element must be @code{baz} |
cc6d0d2c RS |
849 | and whose remaining arguments should be zero or more of @code{foo} and |
850 | @code{bar}, use this customization type: | |
851 | ||
852 | @example | |
241f79af | 853 | (list (const baz) (set :inline t (const foo) (const bar))) |
cc6d0d2c RS |
854 | @end example |
855 | ||
856 | @noindent | |
241f79af PA |
857 | This matches values such as @code{(baz)}, @code{(baz foo)}, @code{(baz bar)} |
858 | and @code{(baz foo bar)}. | |
cc6d0d2c RS |
859 | |
860 | When the element-type is a @code{choice}, you use @code{:inline} not | |
861 | in the @code{choice} itself, but in (some of) the alternatives of the | |
862 | @code{choice}. For example, to match a list which must start with a | |
863 | file name, followed either by the symbol @code{t} or two strings, use | |
864 | this customization type: | |
865 | ||
866 | @example | |
867 | (list file | |
868 | (choice (const t) | |
869 | (list :inline t string string))) | |
870 | @end example | |
871 | ||
872 | @noindent | |
873 | If the user chooses the first alternative in the choice, then the | |
874 | overall list has two elements and the second element is @code{t}. If | |
875 | the user chooses the second alternative, then the overall list has three | |
876 | elements and the second and third must be strings. | |
877 | ||
878 | @node Type Keywords | |
879 | @subsection Type Keywords | |
880 | ||
881 | You can specify keyword-argument pairs in a customization type after the | |
882 | type name symbol. Here are the keywords you can use, and their | |
883 | meanings: | |
884 | ||
885 | @table @code | |
886 | @item :value @var{default} | |
887 | This is used for a type that appears as an alternative inside of | |
969fe9b5 | 888 | @code{choice}; it specifies the default value to use, at first, if and |
cc6d0d2c RS |
889 | when the user selects this alternative with the menu in the |
890 | customization buffer. | |
891 | ||
892 | Of course, if the actual value of the option fits this alternative, it | |
893 | will appear showing the actual value, not @var{default}. | |
894 | ||
969fe9b5 RS |
895 | If @code{nil} is not a valid value for the alternative, then it is |
896 | essential to specify a valid default with @code{:value}. | |
897 | ||
cc6d0d2c RS |
898 | @item :format @var{format-string} |
899 | This string will be inserted in the buffer to represent the value | |
900 | corresponding to the type. The following @samp{%} escapes are available | |
901 | for use in @var{format-string}: | |
902 | ||
903 | @table @samp | |
cc6d0d2c RS |
904 | @item %[@var{button}%] |
905 | Display the text @var{button} marked as a button. The @code{:action} | |
906 | attribute specifies what the button will do if the user invokes it; | |
907 | its value is a function which takes two arguments---the widget which | |
908 | the button appears in, and the event. | |
909 | ||
910 | There is no way to specify two different buttons with different | |
969fe9b5 | 911 | actions. |
cc6d0d2c RS |
912 | |
913 | @item %@{@var{sample}%@} | |
914 | Show @var{sample} in a special face specified by @code{:sample-face}. | |
915 | ||
916 | @item %v | |
917 | Substitute the item's value. How the value is represented depends on | |
918 | the kind of item, and (for variables) on the customization type. | |
919 | ||
920 | @item %d | |
921 | Substitute the item's documentation string. | |
922 | ||
923 | @item %h | |
924 | Like @samp{%d}, but if the documentation string is more than one line, | |
925 | add an active field to control whether to show all of it or just the | |
926 | first line. | |
927 | ||
928 | @item %t | |
929 | Substitute the tag here. You specify the tag with the @code{:tag} | |
930 | keyword. | |
931 | ||
932 | @item %% | |
177c0ea7 | 933 | Display a literal @samp{%}. |
cc6d0d2c RS |
934 | @end table |
935 | ||
969fe9b5 RS |
936 | @item :action @var{action} |
937 | Perform @var{action} if the user clicks on a button. | |
938 | ||
cc6d0d2c | 939 | @item :button-face @var{face} |
969fe9b5 RS |
940 | Use the face @var{face} (a face name or a list of face names) for button |
941 | text displayed with @samp{%[@dots{}%]}. | |
cc6d0d2c | 942 | |
969fe9b5 RS |
943 | @item :button-prefix @var{prefix} |
944 | @itemx :button-suffix @var{suffix} | |
cc6d0d2c RS |
945 | These specify the text to display before and after a button. |
946 | Each can be: | |
947 | ||
948 | @table @asis | |
949 | @item @code{nil} | |
950 | No text is inserted. | |
951 | ||
952 | @item a string | |
953 | The string is inserted literally. | |
954 | ||
955 | @item a symbol | |
956 | The symbol's value is used. | |
957 | @end table | |
958 | ||
969fe9b5 RS |
959 | @item :tag @var{tag} |
960 | Use @var{tag} (a string) as the tag for the value (or part of the value) | |
961 | that corresponds to this type. | |
962 | ||
cc6d0d2c | 963 | @item :doc @var{doc} |
969fe9b5 RS |
964 | Use @var{doc} as the documentation string for this value (or part of the |
965 | value) that corresponds to this type. In order for this to work, you | |
966 | must specify a value for @code{:format}, and use @samp{%d} or @samp{%h} | |
967 | in that value. | |
cc6d0d2c | 968 | |
969fe9b5 RS |
969 | The usual reason to specify a documentation string for a type is to |
970 | provide more information about the meanings of alternatives inside a | |
971 | @code{:choice} type or the parts of some other composite type. | |
cc6d0d2c RS |
972 | |
973 | @item :help-echo @var{motion-doc} | |
974 | When you move to this item with @code{widget-forward} or | |
19182f77 DL |
975 | @code{widget-backward}, it will display the string @var{motion-doc} in |
976 | the echo area. In addition, @var{motion-doc} is used as the mouse | |
977 | @code{help-echo} string and may actually be a function or form evaluated | |
17458c91 LT |
978 | to yield a help string. If it is a function, it is called with one |
979 | argument, the widget. | |
e23a63a5 | 980 | @c @xref{Text help-echo}. |
cc6d0d2c RS |
981 | |
982 | @item :match @var{function} | |
969fe9b5 RS |
983 | Specify how to decide whether a value matches the type. The |
984 | corresponding value, @var{function}, should be a function that accepts | |
985 | two arguments, a widget and a value; it should return non-@code{nil} if | |
986 | the value is acceptable. | |
cc6d0d2c RS |
987 | |
988 | @ignore | |
989 | @item :indent @var{columns} | |
990 | Indent this item by @var{columns} columns. The indentation is used for | |
991 | @samp{%n}, and automatically for group names, for checklists and radio | |
992 | buttons, and for editable lists. It affects the whole of the | |
993 | item except for the first line. | |
994 | ||
995 | @item :offset @var{columns} | |
996 | An integer indicating how many extra spaces to indent the subitems of | |
997 | this item. By default, subitems are indented the same as their parent. | |
998 | ||
999 | @item :extra-offset | |
1000 | An integer indicating how many extra spaces to add to this item's | |
1001 | indentation, compared to its parent. | |
1002 | ||
1003 | @item :notify | |
1004 | A function called each time the item or a subitem is changed. The | |
1005 | function is called with two or three arguments. The first argument is | |
1006 | the item itself, the second argument is the item that was changed, and | |
1007 | the third argument is the event leading to the change, if any. | |
1008 | ||
1009 | @item :menu-tag | |
35208b42 | 1010 | A tag used in the menu when the widget is used as an option in a |
cc6d0d2c RS |
1011 | @code{menu-choice} widget. |
1012 | ||
1013 | @item :menu-tag-get | |
35208b42 | 1014 | A function used for finding the tag when the widget is used as an option |
cc6d0d2c RS |
1015 | in a @code{menu-choice} widget. By default, the tag used will be either the |
1016 | @code{:menu-tag} or @code{:tag} property if present, or the @code{princ} | |
1017 | representation of the @code{:value} property if not. | |
1018 | ||
1019 | @item :validate | |
35208b42 RS |
1020 | A function which takes a widget as an argument, and return @code{nil} |
1021 | if the widget's current value is valid for the widget. Otherwise, it | |
1022 | should return the widget containing the invalid data, and set that | |
1023 | widget's @code{:error} property to a string explaining the error. | |
cc6d0d2c RS |
1024 | |
1025 | You can use the function @code{widget-children-validate} for this job; | |
1026 | it tests that all children of @var{widget} are valid. | |
1027 | ||
1028 | @item :tab-order | |
1029 | Specify the order in which widgets are traversed with | |
1030 | @code{widget-forward} or @code{widget-backward}. This is only partially | |
1031 | implemented. | |
1032 | ||
1033 | @enumerate a | |
1034 | @item | |
1035 | Widgets with tabbing order @code{-1} are ignored. | |
1036 | ||
177c0ea7 | 1037 | @item |
cc6d0d2c RS |
1038 | (Unimplemented) When on a widget with tabbing order @var{n}, go to the |
1039 | next widget in the buffer with tabbing order @var{n+1} or @code{nil}, | |
1040 | whichever comes first. | |
1041 | ||
1042 | @item | |
1043 | When on a widget with no tabbing order specified, go to the next widget | |
1044 | in the buffer with a positive tabbing order, or @code{nil} | |
1045 | @end enumerate | |
1046 | ||
1047 | @item :parent | |
a9f0a989 | 1048 | The parent of a nested widget (e.g., a @code{menu-choice} item or an |
cc6d0d2c RS |
1049 | element of a @code{editable-list} widget). |
1050 | ||
1051 | @item :sibling-args | |
1052 | This keyword is only used for members of a @code{radio-button-choice} or | |
1053 | @code{checklist}. The value should be a list of extra keyword | |
1054 | arguments, which will be used when creating the @code{radio-button} or | |
1055 | @code{checkbox} associated with this item. | |
1056 | @end ignore | |
1057 | @end table | |
ab5796a9 MB |
1058 | |
1059 | @ignore | |
1060 | arch-tag: d1b8fad3-f48c-4ce4-a402-f73b5ef19bd2 | |
1061 | @end ignore |