5 @settitle The Customization Library
12 @node Top, Introduction, (dir), (dir)
13 @comment node-name, next, previous, up
14 @top The Customization Library
21 * The Customization Buffer::
28 @node Introduction, User Commands, Top, Top
29 @comment node-name, next, previous, up
32 This library allows customization of @dfn{user options}. Currently two
33 types of user options are supported, namely @dfn{variables} and
34 @dfn{faces}. Each user option can have four different values
38 The value specified by the programmer.
40 The value saved by the user as the default for this variable. This
41 overwrites the factory setting when starting a new emacs.
43 The value used by Emacs. This will not be remembered next time you
46 The value entered by the user in a customization buffer, but not yet
50 Variables also have a @dfn{type}, which specifies what kind of values
51 the variable can hold, and how the value is presented in a customization
52 buffer. By default a variable can hold any valid expression, but the
53 programmer can specify a more limited type when declaring the variable.
55 The user options are organized in a number of @dfn{groups}. Each group
56 can contain a number user options, as well as other groups. The groups
57 allows the user to concentrate on a specific part of emacs.
59 @node User Commands, The Customization Buffer, Introduction, Top
60 @comment node-name, next, previous, up
61 @section User Commands
63 The following commands will create a customization buffer:
67 Create a customization buffer containing a specific group, by default
68 the @code{emacs} group.
70 @item customize-variable
71 Create a customization buffer containing a single variable.
74 Create a customization buffer containing a single face.
76 @item customize-apropos
77 Create a customization buffer containing all variables, faces, and
78 groups that match a user specified regular expression.
81 @node The Customization Buffer, Declarations, User Commands, Top
82 @comment node-name, next, previous, up
83 @section The Customization Buffer.
85 The customization buffer allows the user to make temporary or permanent
86 changes to how specific aspects of emacs works, by setting and editing
89 The customization buffer contains three types of text:
92 @item informative text
93 where the normal editing commands are disabled.
96 where you can edit with the usual emacs commands. Editable fields are
97 usually displayed with a grey background if your terminal supports
98 colors, or an italic font otherwise.
101 which can be activated by either pressing the @kbd{@key{ret}} while
102 point is located on the text, or pushing @kbd{mouse-2} while the mouse
103 pointer is above the tex. Buttons are usually displayed in a bold
107 You can move to the next the next editable field or button by pressing
108 @kbd{@key{tab}} or the previous with @kbd{M-@key{tab}}. Some buttons
109 have a small helpful message about their purpose, which will be
110 displayed when you move to it with the @key{tab} key.
112 The buffer is divided into three part, an introductory text, a list of
113 customization options, and a line of customization buttons. Each part
114 will be described in the following.
117 * The Introductory Text::
118 * The Customization Options::
119 * The Variable Options::
121 * The Group Options::
123 * The Customization Buttons::
126 @node The Introductory Text, The Customization Options, The Customization Buffer, The Customization Buffer
127 @comment node-name, next, previous, up
128 @subsection The Introductory Text
130 The start of the buffer contains a short explanation of what it is, and
131 how to get help. It will typically look like this:
134 This is a customization buffer.
135 Push RET or click mouse-2 on the word _help_ for more information.
138 Rather boring. It is mostly just informative text, but the word
139 @samp{help} is a button that will bring up this document when
142 @node The Customization Options, The Variable Options, The Introductory Text, The Customization Buffer
143 @comment node-name, next, previous, up
144 @subsection The Customization Options
146 Each customization option looks similar to the following text:
149 *** custom-background-mode: default
150 State: this item is unchanged from its factory setting.
151 [ ] [?] The brightness of the background.
154 The option contains the parts described below.
158 The Level Button. The customization options in the buffer are organized
159 in a hierarchy, which is indicated by the number of stars in the level
160 button. The top level options will be shown as @samp{*}. When they are
161 expanded, the suboptions will be shown as @samp{**}. The example option
162 is thus a subsuboption.
164 Activating the level buttons will toggle between hiding and exposing the
165 content of that option. The content can either be the value of the
166 option, as in this example, or a list of suboptions.
168 @item custom-background-mode
169 This is the tag of the the option. The tag is a name of a variable, a
170 face, or customization group. Activating the tag has an effect that
171 depends on the exact type of the option. In this particular case,
172 activating the tag will bring up a menu that will allow you to choose
173 from the three possible values of the `custom-background-mode'
177 After the tag, the options value is shown. Depending on its type, you
178 may be able to edit the value directly. If an option should contain a
179 file name, it is displayed in an editable field, i.e. you can edit it
180 using the standard emacs editing commands.
182 @item State: this item is unchanged from its factory setting.
183 The state line. This line will explain the state of the option,
184 e.g. whether it is currently hidden, or whether it has been modified or
185 not. Activating the button will allow you to change the state, e.g. set
186 or reset the changes you have made. This is explained in detail in the
190 The magic button. This is an abbreviated version of the state line.
193 The documentation button. If the documentation is more than one line,
194 this button will be present. Activating the button will toggle whether
195 the complete documentation is shown, or only the first line.
197 @item The brightness of the background.
198 This is a documentation string explaining the purpose of this particular
199 customization option.
203 @node The Variable Options, The Face Options, The Customization Options, The Customization Buffer
204 @comment node-name, next, previous, up
205 @subsection The Variable Options
207 The most common customization options are emacs lisp variables. The
208 actual editing of these variables depend on what type values the
209 variable is expected to contain. For example, a lisp variable whose
210 value should be a string will typically be represented with an editable
211 text field in the buffer, where you can change the string directly. If
212 the value is a list, each item in the list will be presented in the
213 buffer buffer on a separate line, with buttons to insert new items in
214 the list, or delete existing items from the list. You may want to see
215 @ref{User Interface,,, widget, The Widget Library}, where some examples
216 of editing are discussed.
218 You can either choose to edit the value directly, or edit the lisp
219 value for that variable. The lisp value is a lisp expression that
220 will be evaluated when you start emacs. The result of the evaluation
221 will be used as the initial value for that variable. Editing the
222 lisp value is for experts only, but if the current value of the
223 variable is of a wrong type (i.e. a symbol where a string is expected),
224 the `edit lisp' mode will always be selected.
226 You can see what mode is currently selected by looking at the state
227 button. If it uses parenthesises (like @samp{( )}) it is in edit lisp
228 mode, with square brackets (like @samp{[ ]}) it is normal edit mode.
229 You can switch mode by activating the state button, and select either
230 @samp{Edit} or @samp{Edit lisp} from the menu.
232 You can change the state of the variable with the other menu items:
236 When you have made your modifications in the buffer, you need to
237 activate this item to make the modifications take effect. The
238 modifications will be forgotten next time you run emacs.
241 Unless you activate this item instead! This will mark the modification
242 as permanent, i.e. the changes will be remembered in the next emacs
246 If you have made some modifications and not yet applied them, you can
247 undo the modification by activating this item.
250 Activating this item will reset the value of the variable to the last
251 value you marked as permanent with `Save'.
253 @item Reset to Factory Settings
254 Activating this item will undo all modifications you have made, and
255 reset the value to the initial value specified by the program itself.
258 By default, the value of large or complicated variables are hidden. You
259 can show the value by clicking on the level button.
261 @node The Face Options, The Group Options, The Variable Options, The Customization Buffer
262 @comment node-name, next, previous, up
263 @subsection The Face Options
265 A face is an object that controls the appearance of some buffer text.
266 The face has a number of possible attributes, such as boldness,
267 foreground color, and more. For each attribute you can specify whether
268 this attribute is controlled by the face, and if so, what the value is.
269 For example, if the attribute bold is not controlled by a face, using
270 that face on some buffer text will not affect its boldness. If the bold
271 attribute is controlled by the face, it can be turned either on or of.
273 It is possible to specify that a face should have different attributes
274 on different device types. For example, a face may make text red on a
275 color device, and bold on a monochrome device. You do this by
276 activating `Edit All' in the state menu.
278 The way this is presented in the customization buffer is to have a list
279 of display specifications, and for each display specification a list of
280 face attributes. For each face attribute, there is a checkbox
281 specifying whether this attribute has effect and what the value is.
285 *** custom-invalid-face: (sample)
286 State: this item is unchanged from its factory setting.
287 [ ] Face used when the customize item is invalid.
288 [INS] [DEL] Display: [ ] Type: [ ] X [ ] PM [ ] Win32 [ ] DOS [ ] TTY
289 [X] Class: [X] Color [ ] Grayscale [ ] Monochrome
290 [ ] Background: [ ] Light [ ] Dark
291 Attributes: [ ] Bold: off
294 [X] Foreground: yellow (sample)
295 [X] Background: red (sample)
297 [INS] [DEL] Display: all
298 Attributes: [X] Bold: on
301 [ ] Foreground: default (sample)
302 [ ] Background: default (sample)
307 This has two display specifications. The first will match all color
308 displays, independently on what window system the device belongs to, and
309 whether background color is dark or light. For devices matching this
310 specification, @samp{custom-invalid-face} will force text to be
311 displayed in yellow on red, but leave all other attributes alone.
313 The second display will simply match everything. Since the list is
314 prioritised, this means that it will match all non-color displays. For
315 these, the face will not affect the foreground or background color, but
316 force the font to be both bold, italic, and underline.
318 You can add or delete display specifications by activating the
319 @samp{[INS]} and @samp{[DEL]} buttons, and modify them by clicking on
320 the check boxes. The first checkbox in each line in the display
321 specification is special. It specify whether this particular property
322 will even be relevant. By not checking the box in the first display, we
323 match all device types, also device types other than those listed.
325 After modifying the face, you can activate the state button to make the
326 changes take effect. The menu items in the state button menu is similar
327 to the state menu items for variables described in the previous section.
329 @node The Group Options, The State Button, The Face Options, The Customization Buffer
330 @comment node-name, next, previous, up
331 @subsection The Group Options
333 Since Emacs has approximately a zillion configuration options, they have
334 been organized in groups. Each group can contain other groups, thus
335 creating a customization hierarchy. The nesting of the customization
336 within the visible part of this hierarchy is indicated by the number of
337 stars in the level button.
339 Since there is really no customization needed for the group itself, the
340 menu items in the groups state button will affect all modified group
341 members recursively. Thus, if you activate the @samp{Set} menu item,
342 all variables and faces that have been modified and belong to that group
343 will be applied. For those members that themselves are groups, it will
344 work as if you had activated the @samp{Set} menu item on them as well.
346 @node The State Button, The Customization Buttons, The Group Options, The Customization Buffer
347 @comment node-name, next, previous, up
348 @subsection The State Line and The Magic Button
350 The state line has two purposes. The first is to hold the state menu,
351 as described in the previous sections. The second is to indicate the
352 state of each customization item.
354 For the magic button, this is done by the character inside the brackets.
355 The following states have been defined, the first that applies to the
356 current item will be used:
360 The option is currently hidden. For group options that means the
361 members are not shown, for variables and faces that the value is not
362 shown. You cannot perform any of the state change operations on a
363 hidden customization option.
366 The value if this option has been modified in the buffer, but not yet
370 The item has has been set by the user.
373 The current value of this option is different from the saved value.
376 The saved value of this option is different from the factory setting.
379 The factory setting of this option is not known. This occurs when you
380 try to customize variables or faces that have not been explicitly
381 declared as customizable.
384 The factory setting is still in effect.
388 For non-hidden group options, the state shown is the most severe state
389 of its members, where more severe means that it appears earlier in the
390 list above (except hidden members, which are ignored).
392 @node The Customization Buttons, , The State Button, The Customization Buffer
393 @comment node-name, next, previous, up
394 @subsection The Customization Buttons
396 The last part of the customization buffer looks like this:
399 [Set] [Save] [Reset] [Done]
402 Activating the @samp{[Set]}, @samp{[Save]}, or @samp{[Reset]}
403 button will affect all modified customization items that are visible in
404 the buffer. @samp{[Done]} will bury the buffer.
406 @node Declarations, Utilities, The Customization Buffer, Top
407 @comment node-name, next, previous, up
408 @section Declarations
410 This section describes how to declare customization groups, variables,
411 and faces. It doesn't contain any examples, but please look at the file
412 @file{cus-edit.el} which contains many declarations you can learn from.
416 * Declaring Variables::
418 * Usage for Package Authors::
421 All the customization declarations can be changes by keyword arguments.
422 Groups, variables, and faces all share these common keywords:
426 @var{value} should be a customization group.
427 Add @var{symbol} to that group.
429 @var{value} should be a widget type.
430 Add @var{value} to the extrenal links for this customization option.
431 Useful widget types include @code{custom-manual}, @code{info-link}, and
434 Add @var{value} to the files that should be loaded nefore displaying
435 this customization option. The value should be iether a string, which
436 should be a string which will be loaded with @code{load-library} unless
437 present in @code{load-history}, or a symbol which will be loaded with
440 @var{Value} should be a short string used for identifying the option in
441 customization menus and buffers. By default the tag will be
442 automatically created from the options name.
445 @node Declaring Groups, Declaring Variables, Declarations, Declarations
446 @comment node-name, next, previous, up
447 @subsection Declaring Groups
449 Use @code{defgroup} to declare new customization groups.
451 @defun defgroup symbol members doc [keyword value]...
452 Declare @var{symbol} as a customization group containing @var{members}.
453 @var{symbol} does not need to be quoted.
455 @var{doc} is the group documentation.
457 @var{members} should be an alist of the form ((@var{name}
458 @var{widget})...) where @var{name} is a symbol and @var{widget} is a
459 widget for editing that symbol. Useful widgets are
460 @code{custom-variable} for editing variables, @code{custom-face} for
461 editing faces, and @code{custom-group} for editing groups.@refill
463 Internally, custom uses the symbol property @code{custom-group} to keep
464 track of the group members, and @code{group-documentation} for the
465 documentation string.
467 The following additional @var{keyword}'s are defined:
471 @var{value} should be a string. If the string is a prefix for the name
472 of a member of the group, that prefix will be ignored when creating a
477 @node Declaring Variables, Declaring Faces, Declaring Groups, Declarations
478 @comment node-name, next, previous, up
479 @subsection Declaring Variables
481 Use @code{defcustom} to declare user editable variables.
483 @defun defcustom symbol value doc [keyword value]...
484 Declare @var{symbol} as a customizable variable that defaults to @var{value}.
485 Neither @var{symbol} nor @var{value} needs to be quoted.
486 If @var{symbol} is not already bound, initialize it to @var{value}.
488 @var{doc} is the variable documentation.
490 The following additional @var{keyword}'s are defined:
494 @var{value} should be a widget type.
496 @var{value} should be a list of possible members of the specified type.
497 For hooks, this is a list of function names.
500 @xref{Sexp Types,,,widget,The Widget Library}, for information about
501 widgets to use together with the @code{:type} keyword.
504 Internally, custom uses the symbol property @code{custom-type} to keep
505 track of the variables type, @code{factory-value} for the program
506 specified default value, @code{saved-value} for a value saved by the
507 user, and @code{variable-documentation} for the documentation string.
509 Use @code{custom-add-option} to specify that a specific function is
510 useful as an meber of a hook.
512 @defun custom-add-option symbol option
513 To the variable @var{symbol} add @var{option}.
515 If @var{symbol} is a hook variable, @var{option} should be a hook
516 member. For other types variables, the effect is undefined."
519 @node Declaring Faces, Usage for Package Authors, Declaring Variables, Declarations
520 @comment node-name, next, previous, up
521 @subsection Declaring Faces
523 Faces are declared with @code{defface}.
525 @defun defface face spec doc [keyword value]...
527 Declare @var{face} as a customizable face that defaults to @var{spec}.
528 @var{face} does not need to be quoted.
530 If @var{face} has been set with `custom-set-face', set the face attributes
531 as specified by that function, otherwise set the face attributes
532 according to @var{spec}.
534 @var{doc} is the face documentation.
536 @var{spec} should be an alist of the form @samp{((@var{display} @var{atts})...)}.
538 @var{atts} is a list of face attributes and their values. The possible
539 attributes are defined in the variable `custom-face-attributes'.
540 Alternatively, @var{atts} can be a face in which case the attributes of
543 The @var{atts} of the first entry in @var{spec} where the @var{display}
544 matches the frame should take effect in that frame. @var{display} can
545 either be the symbol `t', which will match all frames, or an alist of
546 the form @samp{((@var{req} @var{item}...)...)}@refill
548 For the @var{display} to match a FRAME, the @var{req} property of the
549 frame must match one of the @var{item}. The following @var{req} are
554 (the value of (window-system))@*
555 Should be one of @code{x} or @code{tty}.
558 (the frame's color support)@*
559 Should be one of @code{color}, @code{grayscale}, or @code{mono}.
562 (what color is used for the background text)@*
563 Should be one of @code{light} or @code{dark}.
566 Internally, custom uses the symbol property @code{factory-face} for the
567 program specified default face properties, @code{saved-face} for
568 properties saved by the user, and @code{face-doc-string} for the
569 documentation string.@refill
573 @node Usage for Package Authors, , Declaring Faces, Declarations
574 @comment node-name, next, previous, up
575 @subsection Usage for Package Authors
577 The recommended usage for the author of a typical emacs lisp package is
578 to create one group identifying the package, and make all user options
579 and faces members of that group. If the package has more than around 20
580 such options, they should be divided into a number of subgroups, with
581 each subgroup being member of the top level group.
583 The top level group for the package should itself be member of one or
584 more of the standard customization groups. There exists a group for
585 each @emph{finder} keyword. Press @kbd{C-c p} to see a list of finder
586 keywords, and add you group to each of them, using the @code{:group}
589 @node Utilities, The Init File, Declarations, Top
590 @comment node-name, next, previous, up
593 These utilities can come in handy when adding customization support.
595 @deffn Widget custom-manual
596 Widget type for specifying the info manual entry for a customization
597 option. It takes one argument, an info address.
600 @defun custom-add-to-group group member widget
601 To existing @var{group} add a new @var{member} of type @var{widget},
602 If there already is an entry for that member, overwrite it.
605 @defun custom-add-link symbol widget
606 To the custom option @var{symbol} add the link @var{widget}.
609 @defun custom-add-load symbol load
610 To the custom option @var{symbol} add the dependency @var{load}.
611 @var{load} should be either a library file name, or a feature name.
614 @defun custom-menu-create symbol &optional name
615 Create menu for customization group @var{symbol}.
616 If optional @var{name} is given, use that as the name of the menu.
617 Otherwise make up a name from @var{symbol}.
618 The menu is in a format applicable to @code{easy-menu-define}.
621 @node The Init File, Wishlist, Utilities, Top
622 @comment node-name, next, previous, up
623 @section The Init File
625 When you save the customizations, call to @code{custom-set-variables},
626 @code{custom-set-faces} are inserted into the file specified by
627 @code{custom-file}. By default @code{custom-file} is your @file{.emacs}
628 file. If you use another file, you must explicitly load it yourself.
629 The two functions will initialize variables and faces as you have
632 @node Wishlist, , The Init File, Top
633 @comment node-name, next, previous, up
638 The menu items should be grayed out when the information is
639 missing. I.e. if a variable doesn't have a factory setting, the user
640 should not be allowed to select the @samp{Factory} menu item.
643 Better support for keyboard operations in the customize buffer.
646 Integrate with @file{w3} so you can customization buffers with much
647 better formatting. I'm thinking about adding a <custom>name</custom>
648 tag. The latest w3 have some support for this, so come up with a
652 Add an `examples' section, with explained examples of custom type
656 Support selectable color themes. I.e., change many faces by setting one
660 Support undo using lmi's @file{gnus-undo.el}.
663 Make it possible to append to `choice', `radio', and `set' options.
666 Make it possible to customize code, for example to enable or disable a
670 Ask whether set or modified variables should be saved in
671 @code{kill-buffer-hook}.
673 Ditto for @code{kill-emacs-query-functions}.
676 Command to check if there are any customization options that
677 does not belong to an existing group.
680 Optionally disable the point-cursor and instead highlight the selected
681 item in XEmacs. This is like the *Completions* buffer in XEmacs.
682 Suggested by Jens Lautenbacher
683 @samp{<jens@@lemming0.lem.uni-karlsruhe.de>}.@refill
686 Empty customization groups should start open (harder than it looks).
689 Make it possible to include a comment/remark/annotation when saving an