Mercurial > hg > xemacs-beta
annotate man/lispref/minibuf.texi @ 5908:6174848f3e6c
Use parse_integer() in read_atom(); support bases with ratios like integers
src/ChangeLog addition:
2015-05-08 Aidan Kehoe <kehoea@parhasard.net>
* data.c (init_errors_once_early):
Move the Qunsupported_type here from numbers.c, so it's available
when the majority of our types are not supported.
* general-slots.h: Add it here, too.
* number.c: Remove the definition of Qunsupported_type from here.
* lread.c (read_atom):
Check if the first character could reflect a rational, if so, call
parse_integer(), don't check the syntax of the other
characters. This allows us to accept the non-ASCII digit
characters too.
If that worked partially, but not completely, and the next char is
a slash, try to parse as a ratio.
If that fails, try isfloat_string(), but only if the first
character could plausibly be part of a float.
Otherwise, treat as a symbol.
* lread.c (read_rational):
Rename from read_integer. Handle ratios with the same radix
specification as was used for integers.
* lread.c (read1):
Rename read_integer in this function. Support the Common Lisp
#NNNrMMM syntax for parsing a number MMM of arbitrary radix NNN.
man/ChangeLog addition:
2015-05-08 Aidan Kehoe <kehoea@parhasard.net>
* lispref/numbers.texi (Numbers):
Describe the newly-supported arbitrary-base syntax for rationals
(integers and ratios). Describe that ratios can take the same base
specification as integers, something also new.
tests/ChangeLog addition:
2015-05-08 Aidan Kehoe <kehoea@parhasard.net>
* automated/lisp-reader-tests.el:
Check the arbitrary-base integer reader syntax support, just
added. Check the reader base support for ratios, just added.
Check the non-ASCII-digit support in the reader, just added.
| author | Aidan Kehoe <kehoea@parhasard.net> |
|---|---|
| date | Sat, 09 May 2015 00:40:57 +0100 |
| parents | 9fae6227ede5 |
| children |
| rev | line source |
|---|---|
| 428 | 1 @c -*-texinfo-*- |
| 2 @c This is part of the XEmacs Lisp Reference Manual. | |
| 444 | 3 @c Copyright (C) 1990, 1991, 1992, 1993, 1994, 1997 Free Software Foundation, Inc. |
| 428 | 4 @c See the file lispref.texi for copying conditions. |
| 5 @setfilename ../../info/minibuf.info | |
| 6 @node Minibuffers, Command Loop, Read and Print, Top | |
| 7 @chapter Minibuffers | |
| 8 @cindex arguments, reading | |
| 9 @cindex complex arguments | |
| 10 @cindex minibuffer | |
| 11 | |
| 12 A @dfn{minibuffer} is a special buffer that XEmacs commands use to read | |
| 13 arguments more complicated than the single numeric prefix argument. | |
| 14 These arguments include file names, buffer names, and command names (as | |
| 15 in @kbd{M-x}). The minibuffer is displayed on the bottom line of the | |
| 16 frame, in the same place as the echo area, but only while it is in | |
| 17 use for reading an argument. | |
| 18 | |
| 19 @menu | |
| 20 * Intro to Minibuffers:: Basic information about minibuffers. | |
| 21 * Text from Minibuffer:: How to read a straight text string. | |
| 22 * Object from Minibuffer:: How to read a Lisp object or expression. | |
| 23 * Minibuffer History:: Recording previous minibuffer inputs | |
| 24 so the user can reuse them. | |
| 25 * Completion:: How to invoke and customize completion. | |
| 26 * Yes-or-No Queries:: Asking a question with a simple answer. | |
| 27 * Multiple Queries:: Asking a series of similar questions. | |
| 434 | 28 * Reading a Password:: Reading a password from the terminal. |
| 428 | 29 * Minibuffer Misc:: Various customization hooks and variables. |
| 30 @end menu | |
| 31 | |
|
5791
9fae6227ede5
Silence texinfo 5.2 warnings, primarily by adding next, prev, and up
Jerry James <james@xemacs.org>
parents:
444
diff
changeset
|
32 @node Intro to Minibuffers, Text from Minibuffer, Minibuffers, Minibuffers |
| 428 | 33 @section Introduction to Minibuffers |
| 34 | |
| 35 In most ways, a minibuffer is a normal XEmacs buffer. Most operations | |
| 36 @emph{within} a buffer, such as editing commands, work normally in a | |
| 37 minibuffer. However, many operations for managing buffers do not apply | |
| 38 to minibuffers. The name of a minibuffer always has the form @w{@samp{ | |
| 39 *Minibuf-@var{number}}}, and it cannot be changed. Minibuffers are | |
| 40 displayed only in special windows used only for minibuffers; these | |
| 434 | 41 windows always appear at the bottom of a frame. (Sometimes frames have |
| 428 | 42 no minibuffer window, and sometimes a special kind of frame contains |
| 43 nothing but a minibuffer window; see @ref{Minibuffers and Frames}.) | |
| 44 | |
| 45 The minibuffer's window is normally a single line. You can resize it | |
| 46 temporarily with the window sizing commands; it reverts to its normal | |
| 47 size when the minibuffer is exited. You can resize it permanently by | |
| 48 using the window sizing commands in the frame's other window, when the | |
| 49 minibuffer is not active. If the frame contains just a minibuffer, you | |
| 50 can change the minibuffer's size by changing the frame's size. | |
| 51 | |
| 52 If a command uses a minibuffer while there is an active minibuffer, | |
| 53 this is called a @dfn{recursive minibuffer}. The first minibuffer is | |
| 54 named @w{@samp{ *Minibuf-0*}}. Recursive minibuffers are named by | |
| 55 incrementing the number at the end of the name. (The names begin with a | |
| 56 space so that they won't show up in normal buffer lists.) Of several | |
| 57 recursive minibuffers, the innermost (or most recently entered) is the | |
| 58 active minibuffer. We usually call this ``the'' minibuffer. You can | |
| 59 permit or forbid recursive minibuffers by setting the variable | |
| 60 @code{enable-recursive-minibuffers}. | |
| 61 | |
| 62 Like other buffers, a minibuffer may use any of several local keymaps | |
| 63 (@pxref{Keymaps}); these contain various exit commands and in some cases | |
| 64 completion commands (@pxref{Completion}). | |
| 65 | |
| 66 @itemize @bullet | |
| 67 @item | |
| 68 @code{minibuffer-local-map} is for ordinary input (no completion). | |
| 69 | |
| 70 @item | |
| 71 @code{minibuffer-local-completion-map} is for permissive completion. | |
| 72 | |
| 73 @item | |
| 74 @code{minibuffer-local-must-match-map} is for strict completion and | |
| 75 for cautious completion. | |
| 76 @end itemize | |
| 77 | |
|
5791
9fae6227ede5
Silence texinfo 5.2 warnings, primarily by adding next, prev, and up
Jerry James <james@xemacs.org>
parents:
444
diff
changeset
|
78 @node Text from Minibuffer, Object from Minibuffer, Intro to Minibuffers, Minibuffers |
| 428 | 79 @section Reading Text Strings with the Minibuffer |
| 80 | |
| 81 Most often, the minibuffer is used to read text as a string. It can | |
| 82 also be used to read a Lisp object in textual form. The most basic | |
| 83 primitive for minibuffer input is @code{read-from-minibuffer}; it can do | |
| 84 either one. | |
| 85 | |
| 86 In most cases, you should not call minibuffer input functions in the | |
| 87 middle of a Lisp function. Instead, do all minibuffer input as part of | |
| 88 reading the arguments for a command, in the @code{interactive} spec. | |
| 89 @xref{Defining Commands}. | |
| 90 | |
| 434 | 91 @defun read-from-minibuffer prompt-string &optional initial-contents keymap read hist abbrev-table default |
| 428 | 92 This function is the most general way to get input through the |
| 93 minibuffer. By default, it accepts arbitrary text and returns it as a | |
| 94 string; however, if @var{read} is non-@code{nil}, then it uses | |
| 95 @code{read} to convert the text into a Lisp object (@pxref{Input | |
| 96 Functions}). | |
| 97 | |
| 444 | 98 The first thing this function does is to activate a minibuffer and |
| 428 | 99 display it with @var{prompt-string} as the prompt. This value must be a |
| 100 string. | |
| 101 | |
| 102 Then, if @var{initial-contents} is a string, @code{read-from-minibuffer} | |
| 103 inserts it into the minibuffer, leaving point at the end. The | |
| 104 minibuffer appears with this text as its contents. | |
| 105 | |
| 106 @c Emacs 19 feature | |
| 107 The value of @var{initial-contents} may also be a cons cell of the form | |
| 108 @code{(@var{string} . @var{position})}. This means to insert | |
| 109 @var{string} in the minibuffer but put point @var{position} characters | |
| 110 from the beginning, rather than at the end. | |
| 111 | |
| 434 | 112 When the user types a command to exit the minibuffer, |
| 113 @code{read-from-minibuffer} constructs the return value from the text in | |
| 114 the minibuffer. Normally it returns a string containing that text. | |
| 115 However, if @var{read} is non-@code{nil}, @code{read-from-minibuffer} | |
| 116 reads the text and returns the resulting Lisp object, unevaluated. | |
| 117 (@xref{Input Functions}, for information about reading.) | |
| 118 | |
| 119 The argument @var{default} specifies a default value to make available | |
| 120 through the history commands. It should be a string, or @code{nil}. | |
| 121 | |
| 428 | 122 If @var{keymap} is non-@code{nil}, that keymap is the local keymap to |
| 123 use in the minibuffer. If @var{keymap} is omitted or @code{nil}, the | |
| 124 value of @code{minibuffer-local-map} is used as the keymap. Specifying | |
| 125 a keymap is the most important way to customize the minibuffer for | |
| 126 various applications such as completion. | |
| 127 | |
| 434 | 128 The argument @var{abbrev-table} specifies @code{local-abbrev-table} in |
| 129 the minibuffer (@pxref{Standard Abbrev Tables}). | |
| 130 | |
| 428 | 131 The argument @var{hist} specifies which history list variable to use |
| 132 for saving the input and for history commands used in the minibuffer. | |
| 133 It defaults to @code{minibuffer-history}. @xref{Minibuffer History}. | |
| 134 | |
| 135 When the user types a command to exit the minibuffer, | |
| 136 @code{read-from-minibuffer} uses the text in the minibuffer to produce | |
| 137 its return value. Normally it simply makes a string containing that | |
| 138 text. However, if @var{read} is non-@code{nil}, | |
| 139 @code{read-from-minibuffer} reads the text and returns the resulting | |
| 140 Lisp object, unevaluated. (@xref{Input Functions}, for information | |
| 141 about reading.) | |
| 434 | 142 |
| 143 @strong{Usage note:} The @var{initial-contents} argument and the | |
| 144 @var{default} argument are two alternative features for more or less the | |
| 145 same job. It does not make sense to use both features in a single call | |
| 146 to @code{read-from-minibuffer}. In general, we recommend using | |
| 147 @var{default}, since this permits the user to insert the default value | |
| 148 when it is wanted, but does not burden the user with deleting it from | |
| 149 the minibuffer on other occasions. However, if user is supposed to edit | |
| 150 default value, @var{initial-contents} may be preferred. | |
| 428 | 151 @end defun |
| 152 | |
| 442 | 153 @defun read-string prompt &optional initial history default-value |
| 428 | 154 This function reads a string from the minibuffer and returns it. The |
| 155 arguments @var{prompt} and @var{initial} are used as in | |
| 156 @code{read-from-minibuffer}. The keymap used is | |
| 157 @code{minibuffer-local-map}. | |
| 158 | |
| 444 | 159 The optional argument @var{history}, if non-@code{nil}, specifies a history |
| 442 | 160 list and optionally the initial position in the list. The optional |
| 444 | 161 argument @var{default-value} specifies a default value to return if the user |
| 442 | 162 enters null input; it should be a string. |
| 434 | 163 |
| 164 This function is a simplified interface to the | |
| 428 | 165 @code{read-from-minibuffer} function: |
| 166 | |
| 167 @smallexample | |
| 168 @group | |
| 442 | 169 (read-string @var{prompt} @var{initial} @var{history} @var{default}) |
| 428 | 170 @equiv{} |
| 442 | 171 (read-from-minibuffer @var{prompt} @var{initial} nil nil |
| 172 @var{history} nil @var{default}))) | |
| 428 | 173 @end group |
| 174 @end smallexample | |
| 175 @end defun | |
| 176 | |
| 177 @defvar minibuffer-local-map | |
| 178 This is the default local keymap for reading from the minibuffer. By | |
| 179 default, it makes the following bindings: | |
| 180 | |
| 181 @table @asis | |
| 434 | 182 @item @kbd{C-j} |
| 428 | 183 @code{exit-minibuffer} |
| 184 | |
| 185 @item @key{RET} | |
| 186 @code{exit-minibuffer} | |
| 187 | |
| 188 @item @kbd{C-g} | |
| 189 @code{abort-recursive-edit} | |
| 190 | |
| 191 @item @kbd{M-n} | |
| 192 @code{next-history-element} | |
| 193 | |
| 194 @item @kbd{M-p} | |
| 195 @code{previous-history-element} | |
| 196 | |
| 197 @item @kbd{M-r} | |
| 198 @code{next-matching-history-element} | |
| 199 | |
| 200 @item @kbd{M-s} | |
| 201 @code{previous-matching-history-element} | |
| 202 @end table | |
| 203 @end defvar | |
| 204 | |
|
5791
9fae6227ede5
Silence texinfo 5.2 warnings, primarily by adding next, prev, and up
Jerry James <james@xemacs.org>
parents:
444
diff
changeset
|
205 @node Object from Minibuffer, Minibuffer History, Text from Minibuffer, Minibuffers |
| 428 | 206 @section Reading Lisp Objects with the Minibuffer |
| 207 | |
| 208 This section describes functions for reading Lisp objects with the | |
| 209 minibuffer. | |
| 210 | |
| 442 | 211 @defun read-expression prompt &optional initial history default-value |
| 434 | 212 This function reads a Lisp object using the minibuffer, and returns it |
| 428 | 213 without evaluating it. The arguments @var{prompt} and @var{initial} are |
| 214 used as in @code{read-from-minibuffer}. | |
| 215 | |
| 444 | 216 The optional argument @var{history}, if non-@code{nil}, specifies a history |
| 442 | 217 list and optionally the initial position in the list. The optional |
| 218 argument @var{default-value} specifies a default value to return if the | |
| 219 user enters null input; it should be a string. | |
| 220 | |
| 428 | 221 This is a simplified interface to the |
| 222 @code{read-from-minibuffer} function: | |
| 223 | |
| 224 @smallexample | |
| 225 @group | |
| 442 | 226 (read-expression @var{prompt} @var{initial} @var{history} @var{default-value}) |
| 428 | 227 @equiv{} |
| 442 | 228 (read-from-minibuffer @var{prompt} @var{initial} nil t |
| 229 @var{history} nil @var{default-value}) | |
| 428 | 230 @end group |
| 231 @end smallexample | |
| 232 | |
| 233 Here is an example in which we supply the string @code{"(testing)"} as | |
| 234 initial input: | |
| 235 | |
| 236 @smallexample | |
| 237 @group | |
| 442 | 238 (read-expression |
| 428 | 239 "Enter an expression: " (format "%s" '(testing))) |
| 240 | |
| 241 ;; @r{Here is how the minibuffer is displayed:} | |
| 242 @end group | |
| 243 | |
| 244 @group | |
| 245 ---------- Buffer: Minibuffer ---------- | |
| 246 Enter an expression: (testing)@point{} | |
| 247 ---------- Buffer: Minibuffer ---------- | |
| 248 @end group | |
| 249 @end smallexample | |
| 250 | |
| 251 @noindent | |
| 252 The user can type @key{RET} immediately to use the initial input as a | |
| 253 default, or can edit the input. | |
| 254 @end defun | |
| 255 | |
| 442 | 256 @defun read-minibuffer prompt &optional initial history default-value |
| 257 | |
| 258 This is a FSF Emacs compatible function. Use @code{read-expression} | |
| 259 instead. | |
| 260 @end defun | |
| 261 | |
| 262 @defun eval-minibuffer prompt &optional initial history default-value | |
| 434 | 263 This function reads a Lisp expression using the minibuffer, evaluates |
| 264 it, then returns the result. The arguments @var{prompt} and | |
| 265 @var{initial} are used as in @code{read-from-minibuffer}. | |
| 428 | 266 |
| 444 | 267 The optional argument @var{history}, if non-@code{nil}, specifies a history |
| 442 | 268 list and optionally the initial position in the list. The optional |
| 269 argument @var{default-value} specifies a default value to return if the | |
| 270 user enters null input; it should be a string. | |
| 271 | |
| 428 | 272 This function simply evaluates the result of a call to |
| 442 | 273 @code{read-expression}: |
| 428 | 274 |
| 275 @smallexample | |
| 276 @group | |
| 277 (eval-minibuffer @var{prompt} @var{initial}) | |
| 278 @equiv{} | |
| 442 | 279 (eval (read-expression @var{prompt} @var{initial})) |
| 428 | 280 @end group |
| 281 @end smallexample | |
| 282 @end defun | |
| 283 | |
| 444 | 284 @defun edit-and-eval-command prompt form &optional history |
| 428 | 285 This function reads a Lisp expression in the minibuffer, and then |
| 286 evaluates it. The difference between this command and | |
| 444 | 287 @code{eval-minibuffer} is that here the initial @var{form} is not |
| 428 | 288 optional and it is treated as a Lisp object to be converted to printed |
| 289 representation rather than as a string of text. It is printed with | |
| 290 @code{prin1}, so if it is a string, double-quote characters (@samp{"}) | |
| 291 appear in the initial text. @xref{Output Functions}. | |
| 292 | |
| 293 The first thing @code{edit-and-eval-command} does is to activate the | |
| 294 minibuffer with @var{prompt} as the prompt. Then it inserts the printed | |
| 434 | 295 representation of @var{form} in the minibuffer, and lets the user edit it. |
| 428 | 296 When the user exits the minibuffer, the edited text is read with |
| 297 @code{read} and then evaluated. The resulting value becomes the value | |
| 298 of @code{edit-and-eval-command}. | |
| 299 | |
| 300 In the following example, we offer the user an expression with initial | |
| 301 text which is a valid form already: | |
| 302 | |
| 303 @smallexample | |
| 304 @group | |
| 305 (edit-and-eval-command "Please edit: " '(forward-word 1)) | |
| 306 | |
| 444 | 307 ;; @r{After evaluation of the preceding expression,} |
| 428 | 308 ;; @r{the following appears in the minibuffer:} |
| 309 @end group | |
| 310 | |
| 311 @group | |
| 312 ---------- Buffer: Minibuffer ---------- | |
| 313 Please edit: (forward-word 1)@point{} | |
| 314 ---------- Buffer: Minibuffer ---------- | |
| 315 @end group | |
| 316 @end smallexample | |
| 317 | |
| 318 @noindent | |
| 319 Typing @key{RET} right away would exit the minibuffer and evaluate the | |
| 320 expression, thus moving point forward one word. | |
| 321 @code{edit-and-eval-command} returns @code{t} in this example. | |
| 322 @end defun | |
| 323 | |
|
5791
9fae6227ede5
Silence texinfo 5.2 warnings, primarily by adding next, prev, and up
Jerry James <james@xemacs.org>
parents:
444
diff
changeset
|
324 @node Minibuffer History, Completion, Object from Minibuffer, Minibuffers |
| 428 | 325 @section Minibuffer History |
| 326 @cindex minibuffer history | |
| 327 @cindex history list | |
| 328 | |
| 329 A @dfn{minibuffer history list} records previous minibuffer inputs so | |
| 330 the user can reuse them conveniently. A history list is actually a | |
| 331 symbol, not a list; it is a variable whose value is a list of strings | |
| 332 (previous inputs), most recent first. | |
| 333 | |
| 334 There are many separate history lists, used for different kinds of | |
| 335 inputs. It's the Lisp programmer's job to specify the right history | |
| 336 list for each use of the minibuffer. | |
| 337 | |
| 338 The basic minibuffer input functions @code{read-from-minibuffer} and | |
| 339 @code{completing-read} both accept an optional argument named @var{hist} | |
| 340 which is how you specify the history list. Here are the possible | |
| 341 values: | |
| 342 | |
| 343 @table @asis | |
| 344 @item @var{variable} | |
| 345 Use @var{variable} (a symbol) as the history list. | |
| 346 | |
| 347 @item (@var{variable} . @var{startpos}) | |
| 348 Use @var{variable} (a symbol) as the history list, and assume that the | |
| 349 initial history position is @var{startpos} (an integer, counting from | |
| 350 zero which specifies the most recent element of the history). | |
| 351 | |
| 352 If you specify @var{startpos}, then you should also specify that element | |
| 353 of the history as the initial minibuffer contents, for consistency. | |
| 354 @end table | |
| 355 | |
| 356 If you don't specify @var{hist}, then the default history list | |
| 357 @code{minibuffer-history} is used. For other standard history lists, | |
| 358 see below. You can also create your own history list variable; just | |
| 359 initialize it to @code{nil} before the first use. | |
| 360 | |
| 361 Both @code{read-from-minibuffer} and @code{completing-read} add new | |
| 362 elements to the history list automatically, and provide commands to | |
| 363 allow the user to reuse items on the list. The only thing your program | |
| 364 needs to do to use a history list is to initialize it and to pass its | |
| 365 name to the input functions when you wish. But it is safe to modify the | |
| 366 list by hand when the minibuffer input functions are not using it. | |
| 367 | |
| 434 | 368 Here are some of the standard minibuffer history list variables: |
| 369 | |
| 428 | 370 @defvar minibuffer-history |
| 371 The default history list for minibuffer history input. | |
| 372 @end defvar | |
| 373 | |
| 374 @defvar query-replace-history | |
| 375 A history list for arguments to @code{query-replace} (and similar | |
| 376 arguments to other commands). | |
| 377 @end defvar | |
| 378 | |
| 379 @defvar file-name-history | |
| 380 A history list for file name arguments. | |
| 381 @end defvar | |
| 382 | |
| 383 @defvar regexp-history | |
| 384 A history list for regular expression arguments. | |
| 385 @end defvar | |
| 386 | |
| 387 @defvar extended-command-history | |
| 388 A history list for arguments that are names of extended commands. | |
| 389 @end defvar | |
| 390 | |
| 391 @defvar shell-command-history | |
| 392 A history list for arguments that are shell commands. | |
| 393 @end defvar | |
| 394 | |
| 395 @defvar read-expression-history | |
| 396 A history list for arguments that are Lisp expressions to evaluate. | |
| 397 @end defvar | |
| 398 | |
| 399 @defvar Info-minibuffer-history | |
| 400 A history list for Info mode's minibuffer. | |
| 401 @end defvar | |
| 402 | |
| 403 @defvar Manual-page-minibuffer-history | |
| 404 A history list for @code{manual-entry}. | |
| 405 @end defvar | |
| 406 | |
| 407 There are many other minibuffer history lists, defined by various | |
| 408 libraries. An @kbd{M-x apropos} search for @samp{history} should prove | |
| 409 fruitful in discovering them. | |
| 410 | |
|
5791
9fae6227ede5
Silence texinfo 5.2 warnings, primarily by adding next, prev, and up
Jerry James <james@xemacs.org>
parents:
444
diff
changeset
|
411 @node Completion, Yes-or-No Queries, Minibuffer History, Minibuffers |
| 428 | 412 @section Completion |
| 413 @cindex completion | |
| 414 | |
| 415 @dfn{Completion} is a feature that fills in the rest of a name | |
| 416 starting from an abbreviation for it. Completion works by comparing the | |
| 417 user's input against a list of valid names and determining how much of | |
| 418 the name is determined uniquely by what the user has typed. For | |
| 419 example, when you type @kbd{C-x b} (@code{switch-to-buffer}) and then | |
| 420 type the first few letters of the name of the buffer to which you wish | |
| 421 to switch, and then type @key{TAB} (@code{minibuffer-complete}), Emacs | |
| 422 extends the name as far as it can. | |
| 423 | |
| 424 Standard XEmacs commands offer completion for names of symbols, files, | |
| 425 buffers, and processes; with the functions in this section, you can | |
| 426 implement completion for other kinds of names. | |
| 427 | |
| 428 The @code{try-completion} function is the basic primitive for | |
| 429 completion: it returns the longest determined completion of a given | |
| 430 initial string, with a given set of strings to match against. | |
| 431 | |
| 432 The function @code{completing-read} provides a higher-level interface | |
| 433 for completion. A call to @code{completing-read} specifies how to | |
| 434 determine the list of valid names. The function then activates the | |
| 435 minibuffer with a local keymap that binds a few keys to commands useful | |
| 436 for completion. Other functions provide convenient simple interfaces | |
| 437 for reading certain kinds of names with completion. | |
| 438 | |
| 439 @menu | |
| 440 * Basic Completion:: Low-level functions for completing strings. | |
| 441 (These are too low level to use the minibuffer.) | |
| 442 * Minibuffer Completion:: Invoking the minibuffer with completion. | |
| 443 * Completion Commands:: Minibuffer commands that do completion. | |
| 444 * High-Level Completion:: Convenient special cases of completion | |
| 445 (reading buffer name, file name, etc.) | |
| 446 * Reading File Names:: Using completion to read file names. | |
| 447 * Programmed Completion:: Finding the completions for a given file name. | |
| 448 @end menu | |
| 449 | |
|
5791
9fae6227ede5
Silence texinfo 5.2 warnings, primarily by adding next, prev, and up
Jerry James <james@xemacs.org>
parents:
444
diff
changeset
|
450 @node Basic Completion, Minibuffer Completion, Completion, Completion |
| 428 | 451 @subsection Basic Completion Functions |
| 452 | |
| 453 The two functions @code{try-completion} and @code{all-completions} | |
| 454 have nothing in themselves to do with minibuffers. We describe them in | |
| 455 this chapter so as to keep them near the higher-level completion | |
| 456 features that do use the minibuffer. | |
| 457 | |
| 458 @defun try-completion string collection &optional predicate | |
| 444 | 459 This function returns the longest common prefix of all possible |
| 428 | 460 completions of @var{string} in @var{collection}. The value of |
| 461 @var{collection} must be an alist, an obarray, or a function that | |
| 462 implements a virtual set of strings (see below). | |
| 463 | |
| 464 Completion compares @var{string} against each of the permissible | |
| 465 completions specified by @var{collection}; if the beginning of the | |
| 466 permissible completion equals @var{string}, it matches. If no permissible | |
| 467 completions match, @code{try-completion} returns @code{nil}. If only | |
| 468 one permissible completion matches, and the match is exact, then | |
| 469 @code{try-completion} returns @code{t}. Otherwise, the value is the | |
| 470 longest initial sequence common to all the permissible completions that | |
| 471 match. | |
| 472 | |
| 473 If @var{collection} is an alist (@pxref{Association Lists}), the | |
| 474 @sc{car}s of the alist elements form the set of permissible completions. | |
| 475 | |
| 476 @cindex obarray in completion | |
| 477 If @var{collection} is an obarray (@pxref{Creating Symbols}), the names | |
| 478 of all symbols in the obarray form the set of permissible completions. The | |
| 479 global variable @code{obarray} holds an obarray containing the names of | |
| 480 all interned Lisp symbols. | |
| 481 | |
| 482 Note that the only valid way to make a new obarray is to create it | |
| 483 empty and then add symbols to it one by one using @code{intern}. | |
| 484 Also, you cannot intern a given symbol in more than one obarray. | |
| 485 | |
| 486 If the argument @var{predicate} is non-@code{nil}, then it must be a | |
| 487 function of one argument. It is used to test each possible match, and | |
| 488 the match is accepted only if @var{predicate} returns non-@code{nil}. | |
| 489 The argument given to @var{predicate} is either a cons cell from the alist | |
| 490 (the @sc{car} of which is a string) or else it is a symbol (@emph{not} a | |
| 491 symbol name) from the obarray. | |
| 492 | |
| 493 You can also use a symbol that is a function as @var{collection}. Then | |
| 494 the function is solely responsible for performing completion; | |
| 495 @code{try-completion} returns whatever this function returns. The | |
| 496 function is called with three arguments: @var{string}, @var{predicate} | |
| 497 and @code{nil}. (The reason for the third argument is so that the same | |
| 498 function can be used in @code{all-completions} and do the appropriate | |
| 499 thing in either case.) @xref{Programmed Completion}. | |
| 500 | |
| 501 In the first of the following examples, the string @samp{foo} is | |
| 502 matched by three of the alist @sc{car}s. All of the matches begin with | |
| 503 the characters @samp{fooba}, so that is the result. In the second | |
| 504 example, there is only one possible match, and it is exact, so the value | |
| 505 is @code{t}. | |
| 506 | |
| 507 @smallexample | |
| 508 @group | |
| 444 | 509 (try-completion |
| 428 | 510 "foo" |
| 511 '(("foobar1" 1) ("barfoo" 2) ("foobaz" 3) ("foobar2" 4))) | |
| 512 @result{} "fooba" | |
| 513 @end group | |
| 514 | |
| 515 @group | |
| 516 (try-completion "foo" '(("barfoo" 2) ("foo" 3))) | |
| 517 @result{} t | |
| 518 @end group | |
| 519 @end smallexample | |
| 520 | |
| 521 In the following example, numerous symbols begin with the characters | |
| 522 @samp{forw}, and all of them begin with the word @samp{forward}. In | |
| 523 most of the symbols, this is followed with a @samp{-}, but not in all, | |
| 524 so no more than @samp{forward} can be completed. | |
| 525 | |
| 526 @smallexample | |
| 527 @group | |
| 528 (try-completion "forw" obarray) | |
| 529 @result{} "forward" | |
| 530 @end group | |
| 531 @end smallexample | |
| 532 | |
| 533 Finally, in the following example, only two of the three possible | |
| 534 matches pass the predicate @code{test} (the string @samp{foobaz} is | |
| 535 too short). Both of those begin with the string @samp{foobar}. | |
| 536 | |
| 537 @smallexample | |
| 538 @group | |
| 444 | 539 (defun test (s) |
| 428 | 540 (> (length (car s)) 6)) |
| 541 @result{} test | |
| 542 @end group | |
| 543 @group | |
| 444 | 544 (try-completion |
| 428 | 545 "foo" |
| 444 | 546 '(("foobar1" 1) ("barfoo" 2) ("foobaz" 3) ("foobar2" 4)) |
| 428 | 547 'test) |
| 548 @result{} "foobar" | |
| 549 @end group | |
| 550 @end smallexample | |
| 551 @end defun | |
| 552 | |
| 444 | 553 @defun all-completions string collection &optional predicate |
| 554 This function returns a list of all possible completions of @var{string}. | |
| 555 The arguments to this function are the same as those of @code{try-completion}. | |
| 428 | 556 |
| 557 If @var{collection} is a function, it is called with three arguments: | |
| 558 @var{string}, @var{predicate} and @code{t}; then @code{all-completions} | |
| 559 returns whatever the function returns. @xref{Programmed Completion}. | |
| 560 | |
| 561 Here is an example, using the function @code{test} shown in the | |
| 562 example for @code{try-completion}: | |
| 563 | |
| 564 @smallexample | |
| 565 @group | |
| 444 | 566 (defun test (s) |
| 428 | 567 (> (length (car s)) 6)) |
| 568 @result{} test | |
| 569 @end group | |
| 570 | |
| 571 @group | |
| 444 | 572 (all-completions |
| 428 | 573 "foo" |
| 574 '(("foobar1" 1) ("barfoo" 2) ("foobaz" 3) ("foobar2" 4)) | |
| 575 'test) | |
| 576 @result{} ("foobar1" "foobar2") | |
| 577 @end group | |
| 578 @end smallexample | |
| 579 @end defun | |
| 580 | |
| 581 @defvar completion-ignore-case | |
| 444 | 582 If the value of this variable is |
| 428 | 583 non-@code{nil}, XEmacs does not consider case significant in completion. |
| 584 @end defvar | |
| 585 | |
|
5791
9fae6227ede5
Silence texinfo 5.2 warnings, primarily by adding next, prev, and up
Jerry James <james@xemacs.org>
parents:
444
diff
changeset
|
586 @node Minibuffer Completion, Completion Commands, Basic Completion, Completion |
| 428 | 587 @subsection Completion and the Minibuffer |
| 588 | |
| 589 This section describes the basic interface for reading from the | |
| 590 minibuffer with completion. | |
| 591 | |
| 434 | 592 @defun completing-read prompt collection &optional predicate require-match initial hist default |
| 428 | 593 This function reads a string in the minibuffer, assisting the user by |
| 594 providing completion. It activates the minibuffer with prompt | |
| 595 @var{prompt}, which must be a string. If @var{initial} is | |
| 596 non-@code{nil}, @code{completing-read} inserts it into the minibuffer as | |
| 597 part of the input. Then it allows the user to edit the input, providing | |
| 598 several commands to attempt completion. | |
| 599 | |
| 600 The actual completion is done by passing @var{collection} and | |
| 601 @var{predicate} to the function @code{try-completion}. This happens in | |
| 602 certain commands bound in the local keymaps used for completion. | |
| 603 | |
| 604 If @var{require-match} is @code{t}, the usual minibuffer exit commands | |
| 605 won't exit unless the input completes to an element of @var{collection}. | |
| 606 If @var{require-match} is neither @code{nil} nor @code{t}, then the exit | |
| 607 commands won't exit unless the input typed is itself an element of | |
| 608 @var{collection}. If @var{require-match} is @code{nil}, the exit | |
| 609 commands work regardless of the input in the minibuffer. | |
| 610 | |
| 434 | 611 However, empty input is always permitted, regardless of the value of |
| 612 @var{require-match}; in that case, @code{completing-read} returns | |
| 613 @var{default}. The value of @var{default} (if non-@code{nil}) is also | |
| 614 available to the user through the history commands. | |
| 615 | |
| 428 | 616 The user can exit with null input by typing @key{RET} with an empty |
| 434 | 617 minibuffer. Then @code{completing-read} returns @code{""}. This is how |
| 618 the user requests whatever default the command uses for the value being | |
| 619 read. The user can return using @key{RET} in this way regardless of the | |
| 620 value of @var{require-match}, and regardless of whether the empty string | |
| 621 is included in @var{collection}. | |
| 428 | 622 |
| 623 The function @code{completing-read} works by calling | |
| 442 | 624 @code{read-expression}. It uses @code{minibuffer-local-completion-map} |
| 428 | 625 as the keymap if @var{require-match} is @code{nil}, and uses |
| 626 @code{minibuffer-local-must-match-map} if @var{require-match} is | |
| 627 non-@code{nil}. @xref{Completion Commands}. | |
| 628 | |
| 629 The argument @var{hist} specifies which history list variable to use for | |
| 630 saving the input and for minibuffer history commands. It defaults to | |
| 631 @code{minibuffer-history}. @xref{Minibuffer History}. | |
| 632 | |
| 633 Completion ignores case when comparing the input against the possible | |
| 634 matches, if the built-in variable @code{completion-ignore-case} is | |
| 635 non-@code{nil}. @xref{Basic Completion}. | |
| 636 | |
| 637 Here's an example of using @code{completing-read}: | |
| 638 | |
| 639 @smallexample | |
| 640 @group | |
| 641 (completing-read | |
| 642 "Complete a foo: " | |
| 643 '(("foobar1" 1) ("barfoo" 2) ("foobaz" 3) ("foobar2" 4)) | |
| 644 nil t "fo") | |
| 645 @end group | |
| 646 | |
| 647 @group | |
| 444 | 648 ;; @r{After evaluation of the preceding expression,} |
| 428 | 649 ;; @r{the following appears in the minibuffer:} |
| 650 | |
| 651 ---------- Buffer: Minibuffer ---------- | |
| 652 Complete a foo: fo@point{} | |
| 653 ---------- Buffer: Minibuffer ---------- | |
| 654 @end group | |
| 655 @end smallexample | |
| 656 | |
| 657 @noindent | |
| 658 If the user then types @kbd{@key{DEL} @key{DEL} b @key{RET}}, | |
| 659 @code{completing-read} returns @code{barfoo}. | |
| 660 | |
| 661 The @code{completing-read} function binds three variables to pass | |
| 662 information to the commands that actually do completion. These | |
| 663 variables are @code{minibuffer-completion-table}, | |
| 664 @code{minibuffer-completion-predicate} and | |
| 665 @code{minibuffer-completion-confirm}. For more information about them, | |
| 666 see @ref{Completion Commands}. | |
| 667 @end defun | |
| 668 | |
|
5791
9fae6227ede5
Silence texinfo 5.2 warnings, primarily by adding next, prev, and up
Jerry James <james@xemacs.org>
parents:
444
diff
changeset
|
669 @node Completion Commands, High-Level Completion, Minibuffer Completion, Completion |
| 428 | 670 @subsection Minibuffer Commands That Do Completion |
| 671 | |
| 672 This section describes the keymaps, commands and user options used in | |
| 673 the minibuffer to do completion. | |
| 674 | |
| 675 @defvar minibuffer-local-completion-map | |
| 676 @code{completing-read} uses this value as the local keymap when an | |
| 677 exact match of one of the completions is not required. By default, this | |
| 678 keymap makes the following bindings: | |
| 679 | |
| 680 @table @asis | |
| 681 @item @kbd{?} | |
| 682 @code{minibuffer-completion-help} | |
| 683 | |
| 684 @item @key{SPC} | |
| 685 @code{minibuffer-complete-word} | |
| 686 | |
| 687 @item @key{TAB} | |
| 688 @code{minibuffer-complete} | |
| 689 @end table | |
| 690 | |
| 691 @noindent | |
| 692 with other characters bound as in @code{minibuffer-local-map} | |
| 693 (@pxref{Text from Minibuffer}). | |
| 694 @end defvar | |
| 695 | |
| 696 @defvar minibuffer-local-must-match-map | |
| 697 @code{completing-read} uses this value as the local keymap when an | |
| 698 exact match of one of the completions is required. Therefore, no keys | |
| 699 are bound to @code{exit-minibuffer}, the command that exits the | |
| 700 minibuffer unconditionally. By default, this keymap makes the following | |
| 701 bindings: | |
| 702 | |
| 703 @table @asis | |
| 704 @item @kbd{?} | |
| 705 @code{minibuffer-completion-help} | |
| 706 | |
| 707 @item @key{SPC} | |
| 708 @code{minibuffer-complete-word} | |
| 709 | |
| 710 @item @key{TAB} | |
| 711 @code{minibuffer-complete} | |
| 712 | |
| 434 | 713 @item @kbd{C-j} |
| 428 | 714 @code{minibuffer-complete-and-exit} |
| 715 | |
| 716 @item @key{RET} | |
| 717 @code{minibuffer-complete-and-exit} | |
| 718 @end table | |
| 719 | |
| 720 @noindent | |
| 721 with other characters bound as in @code{minibuffer-local-map}. | |
| 722 @end defvar | |
| 723 | |
| 724 @defvar minibuffer-completion-table | |
| 725 The value of this variable is the alist or obarray used for completion | |
| 726 in the minibuffer. This is the global variable that contains what | |
| 727 @code{completing-read} passes to @code{try-completion}. It is used by | |
| 728 minibuffer completion commands such as @code{minibuffer-complete-word}. | |
| 729 @end defvar | |
| 730 | |
| 731 @defvar minibuffer-completion-predicate | |
| 732 This variable's value is the predicate that @code{completing-read} | |
| 733 passes to @code{try-completion}. The variable is also used by the other | |
| 734 minibuffer completion functions. | |
| 735 @end defvar | |
| 736 | |
| 737 @deffn Command minibuffer-complete-word | |
| 738 This function completes the minibuffer contents by at most a single | |
| 739 word. Even if the minibuffer contents have only one completion, | |
| 740 @code{minibuffer-complete-word} does not add any characters beyond the | |
| 741 first character that is not a word constituent. @xref{Syntax Tables}. | |
| 742 @end deffn | |
| 743 | |
| 744 @deffn Command minibuffer-complete | |
| 745 This function completes the minibuffer contents as far as possible. | |
| 746 @end deffn | |
| 747 | |
| 748 @deffn Command minibuffer-complete-and-exit | |
| 749 This function completes the minibuffer contents, and exits if | |
| 750 confirmation is not required, i.e., if | |
| 434 | 751 @code{minibuffer-completion-confirm} is @code{nil}. If confirmation |
| 428 | 752 @emph{is} required, it is given by repeating this command |
| 753 immediately---the command is programmed to work without confirmation | |
| 754 when run twice in succession. | |
| 755 @end deffn | |
| 756 | |
| 757 @defvar minibuffer-completion-confirm | |
| 758 When the value of this variable is non-@code{nil}, XEmacs asks for | |
| 759 confirmation of a completion before exiting the minibuffer. The | |
| 760 function @code{minibuffer-complete-and-exit} checks the value of this | |
| 761 variable before it exits. | |
| 762 @end defvar | |
| 763 | |
| 764 @deffn Command minibuffer-completion-help | |
| 765 This function creates a list of the possible completions of the | |
| 766 current minibuffer contents. It works by calling @code{all-completions} | |
| 767 using the value of the variable @code{minibuffer-completion-table} as | |
| 768 the @var{collection} argument, and the value of | |
| 769 @code{minibuffer-completion-predicate} as the @var{predicate} argument. | |
| 770 The list of completions is displayed as text in a buffer named | |
| 771 @samp{*Completions*}. | |
| 772 @end deffn | |
| 773 | |
| 442 | 774 @defun display-completion-list completions &rest cl-keys |
| 428 | 775 This function displays @var{completions} to the stream in |
| 776 @code{standard-output}, usually a buffer. (@xref{Read and Print}, for more | |
| 777 information about streams.) The argument @var{completions} is normally | |
| 778 a list of completions just returned by @code{all-completions}, but it | |
| 779 does not have to be. Each element may be a symbol or a string, either | |
| 780 of which is simply printed, or a list of two strings, which is printed | |
| 781 as if the strings were concatenated. | |
| 782 | |
| 783 This function is called by @code{minibuffer-completion-help}. The | |
| 784 most common way to use it is together with | |
| 785 @code{with-output-to-temp-buffer}, like this: | |
| 786 | |
| 787 @example | |
| 788 (with-output-to-temp-buffer "*Completions*" | |
| 789 (display-completion-list | |
| 790 (all-completions (buffer-string) my-alist))) | |
| 791 @end example | |
| 792 @end defun | |
| 793 | |
| 794 @defopt completion-auto-help | |
| 795 If this variable is non-@code{nil}, the completion commands | |
| 796 automatically display a list of possible completions whenever nothing | |
| 797 can be completed because the next character is not uniquely determined. | |
| 798 @end defopt | |
| 799 | |
|
5791
9fae6227ede5
Silence texinfo 5.2 warnings, primarily by adding next, prev, and up
Jerry James <james@xemacs.org>
parents:
444
diff
changeset
|
800 @node High-Level Completion, Reading File Names, Completion Commands, Completion |
| 428 | 801 @subsection High-Level Completion Functions |
| 802 | |
| 803 This section describes the higher-level convenient functions for | |
| 804 reading certain sorts of names with completion. | |
| 805 | |
| 806 In most cases, you should not call these functions in the middle of a | |
| 807 Lisp function. When possible, do all minibuffer input as part of | |
| 808 reading the arguments for a command, in the @code{interactive} spec. | |
| 809 @xref{Defining Commands}. | |
| 810 | |
| 811 @defun read-buffer prompt &optional default existing | |
| 812 This function reads the name of a buffer and returns it as a string. | |
| 813 The argument @var{default} is the default name to use, the value to | |
| 814 return if the user exits with an empty minibuffer. If non-@code{nil}, | |
| 815 it should be a string or a buffer. It is mentioned in the prompt, but | |
| 816 is not inserted in the minibuffer as initial input. | |
| 817 | |
| 818 If @var{existing} is non-@code{nil}, then the name specified must be | |
| 819 that of an existing buffer. The usual commands to exit the minibuffer | |
| 820 do not exit if the text is not valid, and @key{RET} does completion to | |
| 821 attempt to find a valid name. (However, @var{default} is not checked | |
| 822 for validity; it is returned, whatever it is, if the user exits with the | |
| 823 minibuffer empty.) | |
| 824 | |
| 825 In the following example, the user enters @samp{minibuffer.t}, and | |
| 826 then types @key{RET}. The argument @var{existing} is @code{t}, and the | |
| 827 only buffer name starting with the given input is | |
| 828 @samp{minibuffer.texi}, so that name is the value. | |
| 829 | |
| 830 @example | |
| 831 (read-buffer "Buffer name? " "foo" t) | |
| 832 @group | |
| 444 | 833 ;; @r{After evaluation of the preceding expression,} |
| 428 | 834 ;; @r{the following prompt appears,} |
| 835 ;; @r{with an empty minibuffer:} | |
| 836 @end group | |
| 837 | |
| 838 @group | |
| 839 ---------- Buffer: Minibuffer ---------- | |
| 840 Buffer name? (default foo) @point{} | |
| 841 ---------- Buffer: Minibuffer ---------- | |
| 842 @end group | |
| 843 | |
| 844 @group | |
| 845 ;; @r{The user types @kbd{minibuffer.t @key{RET}}.} | |
| 846 @result{} "minibuffer.texi" | |
| 847 @end group | |
| 848 @end example | |
| 849 @end defun | |
| 850 | |
| 442 | 851 @defun read-command prompt &optional default-value |
| 428 | 852 This function reads the name of a command and returns it as a Lisp |
| 853 symbol. The argument @var{prompt} is used as in | |
| 854 @code{read-from-minibuffer}. Recall that a command is anything for | |
| 855 which @code{commandp} returns @code{t}, and a command name is a symbol | |
| 856 for which @code{commandp} returns @code{t}. @xref{Interactive Call}. | |
| 857 | |
| 442 | 858 The argument @var{default-value} specifies what to return if the user |
| 859 enters null input. It can be a symbol or a string; if it is a string, | |
| 860 @code{read-command} interns it before returning it. If @var{default} is | |
| 861 @code{nil}, that means no default has been specified; then if the user | |
| 862 enters null input, the return value is @code{nil}. | |
| 863 | |
| 428 | 864 @example |
| 865 (read-command "Command name? ") | |
| 866 | |
| 867 @group | |
| 444 | 868 ;; @r{After evaluation of the preceding expression,} |
| 428 | 869 ;; @r{the following prompt appears with an empty minibuffer:} |
| 870 @end group | |
| 871 | |
| 872 @group | |
| 444 | 873 ---------- Buffer: Minibuffer ---------- |
| 874 Command name? | |
| 428 | 875 ---------- Buffer: Minibuffer ---------- |
| 876 @end group | |
| 877 @end example | |
| 878 | |
| 879 @noindent | |
| 880 If the user types @kbd{forward-c @key{RET}}, then this function returns | |
| 881 @code{forward-char}. | |
| 882 | |
| 883 The @code{read-command} function is a simplified interface to the | |
| 884 function @code{completing-read}. It uses the variable @code{obarray} so | |
| 885 as to complete in the set of extant Lisp symbols, and it uses the | |
| 886 @code{commandp} predicate so as to accept only command names: | |
| 887 | |
| 888 @cindex @code{commandp} example | |
| 889 @example | |
| 890 @group | |
| 891 (read-command @var{prompt}) | |
| 892 @equiv{} | |
| 444 | 893 (intern (completing-read @var{prompt} obarray |
| 428 | 894 'commandp t nil)) |
| 895 @end group | |
| 896 @end example | |
| 897 @end defun | |
| 898 | |
| 442 | 899 @defun read-variable prompt &optional default-value |
| 428 | 900 This function reads the name of a user variable and returns it as a |
| 901 symbol. | |
| 902 | |
| 442 | 903 The argument @var{default-value} specifies what to return if the user |
| 904 enters null input. It can be a symbol or a string; if it is a string, | |
| 444 | 905 @code{read-variable} interns it before returning it. If @var{default-value} |
| 442 | 906 is @code{nil}, that means no default has been specified; then if the |
| 907 user enters null input, the return value is @code{nil}. | |
| 908 | |
| 428 | 909 @example |
| 910 @group | |
| 911 (read-variable "Variable name? ") | |
| 912 | |
| 444 | 913 ;; @r{After evaluation of the preceding expression,} |
| 914 ;; @r{the following prompt appears,} | |
| 428 | 915 ;; @r{with an empty minibuffer:} |
| 916 @end group | |
| 917 | |
| 918 @group | |
| 919 ---------- Buffer: Minibuffer ---------- | |
| 920 Variable name? @point{} | |
| 921 ---------- Buffer: Minibuffer ---------- | |
| 922 @end group | |
| 923 @end example | |
| 924 | |
| 925 @noindent | |
| 926 If the user then types @kbd{fill-p @key{RET}}, @code{read-variable} | |
| 927 returns @code{fill-prefix}. | |
| 928 | |
| 929 This function is similar to @code{read-command}, but uses the | |
| 930 predicate @code{user-variable-p} instead of @code{commandp}: | |
| 931 | |
| 932 @cindex @code{user-variable-p} example | |
| 933 @example | |
| 934 @group | |
| 935 (read-variable @var{prompt}) | |
| 936 @equiv{} | |
| 937 (intern | |
| 938 (completing-read @var{prompt} obarray | |
| 939 'user-variable-p t nil)) | |
| 940 @end group | |
| 941 @end example | |
| 942 @end defun | |
| 943 | |
|
5791
9fae6227ede5
Silence texinfo 5.2 warnings, primarily by adding next, prev, and up
Jerry James <james@xemacs.org>
parents:
444
diff
changeset
|
944 @node Reading File Names, Programmed Completion, High-Level Completion, Completion |
| 428 | 945 @subsection Reading File Names |
| 946 | |
| 947 Here is another high-level completion function, designed for reading a | |
| 948 file name. It provides special features including automatic insertion | |
| 949 of the default directory. | |
| 950 | |
| 442 | 951 @defun read-file-name prompt &optional directory default existing initial history |
| 428 | 952 This function reads a file name in the minibuffer, prompting with |
| 953 @var{prompt} and providing completion. If @var{default} is | |
| 954 non-@code{nil}, then the function returns @var{default} if the user just | |
| 955 types @key{RET}. @var{default} is not checked for validity; it is | |
| 956 returned, whatever it is, if the user exits with the minibuffer empty. | |
| 957 | |
| 958 If @var{existing} is non-@code{nil}, then the user must specify the name | |
| 959 of an existing file; @key{RET} performs completion to make the name | |
| 960 valid if possible, and then refuses to exit if it is not valid. If the | |
| 961 value of @var{existing} is neither @code{nil} nor @code{t}, then | |
| 962 @key{RET} also requires confirmation after completion. If | |
| 963 @var{existing} is @code{nil}, then the name of a nonexistent file is | |
| 964 acceptable. | |
| 965 | |
| 966 The argument @var{directory} specifies the directory to use for | |
| 967 completion of relative file names. If @code{insert-default-directory} | |
| 968 is non-@code{nil}, @var{directory} is also inserted in the minibuffer as | |
| 969 initial input. It defaults to the current buffer's value of | |
| 970 @code{default-directory}. | |
| 971 | |
| 972 @c Emacs 19 feature | |
| 973 If you specify @var{initial}, that is an initial file name to insert in | |
| 434 | 974 the buffer (after @var{directory}, if that is inserted). In this |
| 428 | 975 case, point goes at the beginning of @var{initial}. The default for |
| 976 @var{initial} is @code{nil}---don't insert any file name. To see what | |
| 977 @var{initial} does, try the command @kbd{C-x C-v}. | |
| 978 | |
| 444 | 979 Here is an example: |
| 428 | 980 |
| 981 @example | |
| 982 @group | |
| 983 (read-file-name "The file is ") | |
| 984 | |
| 444 | 985 ;; @r{After evaluation of the preceding expression,} |
| 428 | 986 ;; @r{the following appears in the minibuffer:} |
| 987 @end group | |
| 988 | |
| 989 @group | |
| 990 ---------- Buffer: Minibuffer ---------- | |
| 991 The file is /gp/gnu/elisp/@point{} | |
| 992 ---------- Buffer: Minibuffer ---------- | |
| 993 @end group | |
| 994 @end example | |
| 995 | |
| 996 @noindent | |
| 997 Typing @kbd{manual @key{TAB}} results in the following: | |
| 998 | |
| 999 @example | |
| 1000 @group | |
| 1001 ---------- Buffer: Minibuffer ---------- | |
| 1002 The file is /gp/gnu/elisp/manual.texi@point{} | |
| 1003 ---------- Buffer: Minibuffer ---------- | |
| 1004 @end group | |
| 1005 @end example | |
| 1006 | |
| 1007 @c Wordy to avoid overfull hbox in smallbook mode. | |
| 1008 @noindent | |
| 1009 If the user types @key{RET}, @code{read-file-name} returns the file name | |
| 1010 as the string @code{"/gp/gnu/elisp/manual.texi"}. | |
| 1011 @end defun | |
| 1012 | |
| 1013 @defopt insert-default-directory | |
| 1014 This variable is used by @code{read-file-name}. Its value controls | |
| 1015 whether @code{read-file-name} starts by placing the name of the default | |
| 1016 directory in the minibuffer, plus the initial file name if any. If the | |
| 1017 value of this variable is @code{nil}, then @code{read-file-name} does | |
| 1018 not place any initial input in the minibuffer (unless you specify | |
| 1019 initial input with the @var{initial} argument). In that case, the | |
| 1020 default directory is still used for completion of relative file names, | |
| 1021 but is not displayed. | |
| 1022 | |
| 1023 For example: | |
| 1024 | |
| 1025 @example | |
| 1026 @group | |
| 1027 ;; @r{Here the minibuffer starts out with the default directory.} | |
| 1028 (let ((insert-default-directory t)) | |
| 1029 (read-file-name "The file is ")) | |
| 1030 @end group | |
| 1031 | |
| 1032 @group | |
| 1033 ---------- Buffer: Minibuffer ---------- | |
| 1034 The file is ~lewis/manual/@point{} | |
| 1035 ---------- Buffer: Minibuffer ---------- | |
| 1036 @end group | |
| 1037 | |
| 1038 @group | |
| 1039 ;; @r{Here the minibuffer is empty and only the prompt} | |
| 1040 ;; @r{appears on its line.} | |
| 1041 (let ((insert-default-directory nil)) | |
| 1042 (read-file-name "The file is ")) | |
| 1043 @end group | |
| 1044 | |
| 1045 @group | |
| 1046 ---------- Buffer: Minibuffer ---------- | |
| 1047 The file is @point{} | |
| 1048 ---------- Buffer: Minibuffer ---------- | |
| 1049 @end group | |
| 1050 @end example | |
| 1051 @end defopt | |
| 1052 | |
|
5791
9fae6227ede5
Silence texinfo 5.2 warnings, primarily by adding next, prev, and up
Jerry James <james@xemacs.org>
parents:
444
diff
changeset
|
1053 @node Programmed Completion, , Reading File Names, Completion |
| 428 | 1054 @subsection Programmed Completion |
| 1055 @cindex programmed completion | |
| 1056 | |
| 1057 Sometimes it is not possible to create an alist or an obarray | |
| 1058 containing all the intended possible completions. In such a case, you | |
| 1059 can supply your own function to compute the completion of a given string. | |
| 1060 This is called @dfn{programmed completion}. | |
| 1061 | |
| 1062 To use this feature, pass a symbol with a function definition as the | |
| 1063 @var{collection} argument to @code{completing-read}. The function | |
| 1064 @code{completing-read} arranges to pass your completion function along | |
| 1065 to @code{try-completion} and @code{all-completions}, which will then let | |
| 1066 your function do all the work. | |
| 1067 | |
| 1068 The completion function should accept three arguments: | |
| 1069 | |
| 1070 @itemize @bullet | |
| 1071 @item | |
| 1072 The string to be completed. | |
| 1073 | |
| 1074 @item | |
| 1075 The predicate function to filter possible matches, or @code{nil} if | |
| 1076 none. Your function should call the predicate for each possible match, | |
| 1077 and ignore the possible match if the predicate returns @code{nil}. | |
| 1078 | |
| 1079 @item | |
| 1080 A flag specifying the type of operation. | |
| 1081 @end itemize | |
| 1082 | |
| 1083 There are three flag values for three operations: | |
| 1084 | |
| 1085 @itemize @bullet | |
| 1086 @item | |
| 1087 @code{nil} specifies @code{try-completion}. The completion function | |
| 1088 should return the completion of the specified string, or @code{t} if the | |
| 434 | 1089 string is a unique and exact match already, or @code{nil} if the string |
| 1090 matches no possibility. | |
| 1091 | |
| 1092 If the string is an exact match for one possibility, but also matches | |
| 1093 other longer possibilities, the function should return the string, not | |
| 1094 @code{t}. | |
| 428 | 1095 |
| 1096 @item | |
| 1097 @code{t} specifies @code{all-completions}. The completion function | |
| 1098 should return a list of all possible completions of the specified | |
| 1099 string. | |
| 1100 | |
| 1101 @item | |
| 1102 @code{lambda} specifies a test for an exact match. The completion | |
| 1103 function should return @code{t} if the specified string is an exact | |
| 1104 match for some possibility; @code{nil} otherwise. | |
| 1105 @end itemize | |
| 1106 | |
| 1107 It would be consistent and clean for completion functions to allow | |
| 1108 lambda expressions (lists that are functions) as well as function | |
| 1109 symbols as @var{collection}, but this is impossible. Lists as | |
| 1110 completion tables are already assigned another meaning---as alists. It | |
| 1111 would be unreliable to fail to handle an alist normally because it is | |
| 1112 also a possible function. So you must arrange for any function you wish | |
| 1113 to use for completion to be encapsulated in a symbol. | |
| 1114 | |
| 1115 Emacs uses programmed completion when completing file names. | |
| 1116 @xref{File Name Completion}. | |
| 1117 | |
|
5791
9fae6227ede5
Silence texinfo 5.2 warnings, primarily by adding next, prev, and up
Jerry James <james@xemacs.org>
parents:
444
diff
changeset
|
1118 @node Yes-or-No Queries, Multiple Queries, Completion, Minibuffers |
| 428 | 1119 @section Yes-or-No Queries |
| 1120 @cindex asking the user questions | |
| 1121 @cindex querying the user | |
| 1122 @cindex yes-or-no questions | |
| 1123 | |
| 1124 This section describes functions used to ask the user a yes-or-no | |
| 1125 question. The function @code{y-or-n-p} can be answered with a single | |
| 1126 character; it is useful for questions where an inadvertent wrong answer | |
| 1127 will not have serious consequences. @code{yes-or-no-p} is suitable for | |
| 1128 more momentous questions, since it requires three or four characters to | |
| 1129 answer. Variations of these functions can be used to ask a yes-or-no | |
| 1130 question using a dialog box, or optionally using one. | |
| 1131 | |
| 1132 If either of these functions is called in a command that was invoked | |
| 1133 using the mouse, then it uses a dialog box or pop-up menu to ask the | |
| 1134 question. Otherwise, it uses keyboard input. | |
| 1135 | |
| 1136 Strictly speaking, @code{yes-or-no-p} uses the minibuffer and | |
| 1137 @code{y-or-n-p} does not; but it seems best to describe them together. | |
| 1138 | |
| 1139 @defun y-or-n-p prompt | |
| 1140 This function asks the user a question, expecting input in the echo | |
| 1141 area. It returns @code{t} if the user types @kbd{y}, @code{nil} if the | |
| 1142 user types @kbd{n}. This function also accepts @key{SPC} to mean yes | |
| 1143 and @key{DEL} to mean no. It accepts @kbd{C-]} to mean ``quit'', like | |
| 1144 @kbd{C-g}, because the question might look like a minibuffer and for | |
| 1145 that reason the user might try to use @kbd{C-]} to get out. The answer | |
| 1146 is a single character, with no @key{RET} needed to terminate it. Upper | |
| 1147 and lower case are equivalent. | |
| 1148 | |
| 1149 ``Asking the question'' means printing @var{prompt} in the echo area, | |
| 1150 followed by the string @w{@samp{(y or n) }}. If the input is not one of | |
| 1151 the expected answers (@kbd{y}, @kbd{n}, @kbd{@key{SPC}}, | |
| 1152 @kbd{@key{DEL}}, or something that quits), the function responds | |
| 1153 @samp{Please answer y or n.}, and repeats the request. | |
| 1154 | |
| 1155 This function does not actually use the minibuffer, since it does not | |
| 1156 allow editing of the answer. It actually uses the echo area (@pxref{The | |
| 1157 Echo Area}), which uses the same screen space as the minibuffer. The | |
| 1158 cursor moves to the echo area while the question is being asked. | |
| 1159 | |
| 1160 The answers and their meanings, even @samp{y} and @samp{n}, are not | |
| 1161 hardwired. The keymap @code{query-replace-map} specifies them. | |
| 1162 @xref{Search and Replace}. | |
| 1163 | |
| 1164 In the following example, the user first types @kbd{q}, which is | |
| 1165 invalid. At the next prompt the user types @kbd{y}. | |
| 1166 | |
| 1167 @smallexample | |
| 1168 @group | |
| 1169 (y-or-n-p "Do you need a lift? ") | |
| 1170 | |
| 444 | 1171 ;; @r{After evaluation of the preceding expression,} |
| 428 | 1172 ;; @r{the following prompt appears in the echo area:} |
| 1173 @end group | |
| 1174 | |
| 1175 @group | |
| 1176 ---------- Echo area ---------- | |
| 444 | 1177 Do you need a lift? (y or n) |
| 428 | 1178 ---------- Echo area ---------- |
| 1179 @end group | |
| 1180 | |
| 1181 ;; @r{If the user then types @kbd{q}, the following appears:} | |
| 1182 | |
| 1183 @group | |
| 1184 ---------- Echo area ---------- | |
| 444 | 1185 Please answer y or n. Do you need a lift? (y or n) |
| 428 | 1186 ---------- Echo area ---------- |
| 1187 @end group | |
| 1188 | |
| 1189 ;; @r{When the user types a valid answer,} | |
| 1190 ;; @r{it is displayed after the question:} | |
| 1191 | |
| 1192 @group | |
| 1193 ---------- Echo area ---------- | |
| 1194 Do you need a lift? (y or n) y | |
| 1195 ---------- Echo area ---------- | |
| 1196 @end group | |
| 1197 @end smallexample | |
| 1198 | |
| 1199 @noindent | |
| 1200 We show successive lines of echo area messages, but only one actually | |
| 1201 appears on the screen at a time. | |
| 1202 @end defun | |
| 1203 | |
| 1204 @defun yes-or-no-p prompt | |
| 1205 This function asks the user a question, expecting input in the | |
| 1206 minibuffer. It returns @code{t} if the user enters @samp{yes}, | |
| 1207 @code{nil} if the user types @samp{no}. The user must type @key{RET} to | |
| 1208 finalize the response. Upper and lower case are equivalent. | |
| 1209 | |
| 1210 @code{yes-or-no-p} starts by displaying @var{prompt} in the echo area, | |
| 1211 followed by @w{@samp{(yes or no) }}. The user must type one of the | |
| 1212 expected responses; otherwise, the function responds @samp{Please answer | |
| 1213 yes or no.}, waits about two seconds and repeats the request. | |
| 1214 | |
| 1215 @code{yes-or-no-p} requires more work from the user than | |
| 1216 @code{y-or-n-p} and is appropriate for more crucial decisions. | |
| 1217 | |
| 1218 Here is an example: | |
| 1219 | |
| 1220 @smallexample | |
| 1221 @group | |
| 1222 (yes-or-no-p "Do you really want to remove everything? ") | |
| 1223 | |
| 444 | 1224 ;; @r{After evaluation of the preceding expression,} |
| 1225 ;; @r{the following prompt appears,} | |
| 428 | 1226 ;; @r{with an empty minibuffer:} |
| 1227 @end group | |
| 1228 | |
| 1229 @group | |
| 1230 ---------- Buffer: minibuffer ---------- | |
| 444 | 1231 Do you really want to remove everything? (yes or no) |
| 428 | 1232 ---------- Buffer: minibuffer ---------- |
| 1233 @end group | |
| 1234 @end smallexample | |
| 1235 | |
| 1236 @noindent | |
| 1237 If the user first types @kbd{y @key{RET}}, which is invalid because this | |
| 1238 function demands the entire word @samp{yes}, it responds by displaying | |
| 1239 these prompts, with a brief pause between them: | |
| 1240 | |
| 1241 @smallexample | |
| 1242 @group | |
| 1243 ---------- Buffer: minibuffer ---------- | |
| 1244 Please answer yes or no. | |
| 1245 Do you really want to remove everything? (yes or no) | |
| 1246 ---------- Buffer: minibuffer ---------- | |
| 1247 @end group | |
| 1248 @end smallexample | |
| 1249 @end defun | |
| 1250 | |
| 1251 @c The rest is XEmacs stuff | |
| 1252 @defun yes-or-no-p-dialog-box prompt | |
| 1253 This function asks the user a ``y or n'' question with a popup dialog | |
| 1254 box. It returns @code{t} if the answer is ``yes''. @var{prompt} is the | |
| 1255 string to display to ask the question. | |
| 1256 @end defun | |
| 1257 | |
| 1258 The following functions ask a question either in the minibuffer or a | |
| 1259 dialog box, depending on whether the last user event (which presumably | |
| 1260 invoked this command) was a keyboard or mouse event. When XEmacs is | |
| 1261 running on a window system, the functions @code{y-or-n-p} and | |
| 1262 @code{yes-or-no-p} are replaced with the following functions, so that | |
| 1263 menu items bring up dialog boxes instead of minibuffer questions. | |
| 1264 | |
| 1265 @defun y-or-n-p-maybe-dialog-box prompt | |
| 1266 This function asks user a ``y or n'' question, using either a dialog box | |
| 1267 or the minibuffer, as appropriate. | |
| 1268 @end defun | |
| 1269 | |
| 1270 @defun yes-or-no-p-maybe-dialog-box prompt | |
| 1271 This function asks user a ``yes or no'' question, using either a dialog | |
| 1272 box or the minibuffer, as appropriate. | |
| 1273 @end defun | |
| 1274 | |
|
5791
9fae6227ede5
Silence texinfo 5.2 warnings, primarily by adding next, prev, and up
Jerry James <james@xemacs.org>
parents:
444
diff
changeset
|
1275 @node Multiple Queries, Reading a Password, Yes-or-No Queries, Minibuffers |
| 428 | 1276 @section Asking Multiple Y-or-N Questions |
| 1277 | |
| 1278 When you have a series of similar questions to ask, such as ``Do you | |
| 1279 want to save this buffer'' for each buffer in turn, you should use | |
| 1280 @code{map-y-or-n-p} to ask the collection of questions, rather than | |
| 1281 asking each question individually. This gives the user certain | |
| 1282 convenient facilities such as the ability to answer the whole series at | |
| 1283 once. | |
| 1284 | |
| 1285 @defun map-y-or-n-p prompter actor list &optional help action-alist | |
| 1286 This function, new in Emacs 19, asks the user a series of questions, | |
| 1287 reading a single-character answer in the echo area for each one. | |
| 1288 | |
| 1289 The value of @var{list} specifies the objects to ask questions about. | |
| 1290 It should be either a list of objects or a generator function. If it is | |
| 1291 a function, it should expect no arguments, and should return either the | |
| 1292 next object to ask about, or @code{nil} meaning stop asking questions. | |
| 1293 | |
| 1294 The argument @var{prompter} specifies how to ask each question. If | |
| 1295 @var{prompter} is a string, the question text is computed like this: | |
| 1296 | |
| 1297 @example | |
| 1298 (format @var{prompter} @var{object}) | |
| 1299 @end example | |
| 1300 | |
| 1301 @noindent | |
| 1302 where @var{object} is the next object to ask about (as obtained from | |
| 1303 @var{list}). | |
| 1304 | |
| 1305 If not a string, @var{prompter} should be a function of one argument | |
| 1306 (the next object to ask about) and should return the question text. If | |
| 1307 the value is a string, that is the question to ask the user. The | |
| 1308 function can also return @code{t} meaning do act on this object (and | |
| 1309 don't ask the user), or @code{nil} meaning ignore this object (and don't | |
| 1310 ask the user). | |
| 1311 | |
| 1312 The argument @var{actor} says how to act on the answers that the user | |
| 1313 gives. It should be a function of one argument, and it is called with | |
| 1314 each object that the user says yes for. Its argument is always an | |
| 1315 object obtained from @var{list}. | |
| 1316 | |
| 1317 If the argument @var{help} is given, it should be a list of this form: | |
| 1318 | |
| 1319 @example | |
| 1320 (@var{singular} @var{plural} @var{action}) | |
| 1321 @end example | |
| 1322 | |
| 1323 @noindent | |
| 1324 where @var{singular} is a string containing a singular noun that | |
| 1325 describes the objects conceptually being acted on, @var{plural} is the | |
| 1326 corresponding plural noun, and @var{action} is a transitive verb | |
| 1327 describing what @var{actor} does. | |
| 1328 | |
| 1329 If you don't specify @var{help}, the default is @code{("object" | |
| 1330 "objects" "act on")}. | |
| 1331 | |
| 1332 Each time a question is asked, the user may enter @kbd{y}, @kbd{Y}, or | |
| 1333 @key{SPC} to act on that object; @kbd{n}, @kbd{N}, or @key{DEL} to skip | |
| 1334 that object; @kbd{!} to act on all following objects; @key{ESC} or | |
| 1335 @kbd{q} to exit (skip all following objects); @kbd{.} (period) to act on | |
| 1336 the current object and then exit; or @kbd{C-h} to get help. These are | |
| 1337 the same answers that @code{query-replace} accepts. The keymap | |
| 1338 @code{query-replace-map} defines their meaning for @code{map-y-or-n-p} | |
| 1339 as well as for @code{query-replace}; see @ref{Search and Replace}. | |
| 1340 | |
| 1341 You can use @var{action-alist} to specify additional possible answers | |
| 1342 and what they mean. It is an alist of elements of the form | |
| 1343 @code{(@var{char} @var{function} @var{help})}, each of which defines one | |
| 1344 additional answer. In this element, @var{char} is a character (the | |
| 1345 answer); @var{function} is a function of one argument (an object from | |
| 1346 @var{list}); @var{help} is a string. | |
| 1347 | |
| 1348 When the user responds with @var{char}, @code{map-y-or-n-p} calls | |
| 1349 @var{function}. If it returns non-@code{nil}, the object is considered | |
| 1350 ``acted upon'', and @code{map-y-or-n-p} advances to the next object in | |
| 1351 @var{list}. If it returns @code{nil}, the prompt is repeated for the | |
| 1352 same object. | |
| 1353 | |
| 1354 If @code{map-y-or-n-p} is called in a command that was invoked using the | |
| 1355 mouse---more precisely, if @code{last-nonmenu-event} (@pxref{Command | |
| 1356 Loop Info}) is either @code{nil} or a list---then it uses a dialog box | |
| 1357 or pop-up menu to ask the question. In this case, it does not use | |
| 1358 keyboard input or the echo area. You can force use of the mouse or use | |
| 1359 of keyboard input by binding @code{last-nonmenu-event} to a suitable | |
| 1360 value around the call. | |
| 1361 | |
| 1362 The return value of @code{map-y-or-n-p} is the number of objects acted on. | |
| 1363 @end defun | |
| 1364 | |
|
5791
9fae6227ede5
Silence texinfo 5.2 warnings, primarily by adding next, prev, and up
Jerry James <james@xemacs.org>
parents:
444
diff
changeset
|
1365 @node Reading a Password, Minibuffer Misc, Multiple Queries, Minibuffers |
| 434 | 1366 @section Reading a Password |
| 1367 @cindex passwords, reading | |
| 1368 | |
| 1369 To read a password to pass to another program, you can use the | |
| 1370 function @code{read-passwd}. | |
| 1371 | |
| 1372 @defun read-passwd prompt &optional confirm default | |
| 1373 This function reads a password, prompting with @var{prompt}. It does | |
| 1374 not echo the password as the user types it; instead, it echoes @samp{.} | |
| 1375 for each character in the password. | |
| 1376 | |
| 1377 The optional argument @var{confirm}, if non-@code{nil}, says to read the | |
| 1378 password twice and insist it must be the same both times. If it isn't | |
| 1379 the same, the user has to type it over and over until the last two | |
| 1380 times match. | |
| 1381 | |
| 1382 The optional argument @var{default} specifies the default password to | |
| 1383 return if the user enters empty input. It is translated to @samp{.} | |
| 1384 and inserted in the minibuffer. If @var{default} is @code{nil}, then | |
| 1385 @code{read-passwd} returns the null string in that case. | |
| 1386 @end defun | |
| 1387 | |
| 1388 @defopt passwd-invert-frame-when-keyboard-grabbed | |
| 444 | 1389 If non-@code{nil}, swap the foreground and background colors of all faces while |
| 1390 reading a password. Default values is @code{t}, unless feature | |
| 434 | 1391 @code{infodock} is provided. |
| 1392 @end defopt | |
| 1393 | |
| 1394 @defopt passwd-echo | |
| 444 | 1395 This specifies the character echoed when typing a password. When @code{nil}, |
| 434 | 1396 nothing is echoed. |
| 1397 @end defopt | |
| 1398 | |
|
5791
9fae6227ede5
Silence texinfo 5.2 warnings, primarily by adding next, prev, and up
Jerry James <james@xemacs.org>
parents:
444
diff
changeset
|
1399 @node Minibuffer Misc, , Reading a Password, Minibuffers |
| 428 | 1400 @section Minibuffer Miscellany |
| 1401 | |
| 1402 This section describes some basic functions and variables related to | |
| 1403 minibuffers. | |
| 1404 | |
| 1405 @deffn Command exit-minibuffer | |
| 1406 This command exits the active minibuffer. It is normally bound to | |
| 1407 keys in minibuffer local keymaps. | |
| 1408 @end deffn | |
| 1409 | |
| 1410 @deffn Command self-insert-and-exit | |
| 1411 This command exits the active minibuffer after inserting the last | |
| 1412 character typed on the keyboard (found in @code{last-command-char}; | |
| 1413 @pxref{Command Loop Info}). | |
| 1414 @end deffn | |
| 1415 | |
| 1416 @deffn Command previous-history-element n | |
| 1417 This command replaces the minibuffer contents with the value of the | |
| 1418 @var{n}th previous (older) history element. | |
| 1419 @end deffn | |
| 1420 | |
| 1421 @deffn Command next-history-element n | |
| 1422 This command replaces the minibuffer contents with the value of the | |
| 1423 @var{n}th more recent history element. | |
| 1424 @end deffn | |
| 1425 | |
| 1426 @deffn Command previous-matching-history-element pattern | |
| 1427 This command replaces the minibuffer contents with the value of the | |
| 1428 previous (older) history element that matches @var{pattern} (a regular | |
| 1429 expression). | |
| 1430 @end deffn | |
| 1431 | |
| 1432 @deffn Command next-matching-history-element pattern | |
| 1433 This command replaces the minibuffer contents with the value of the next | |
| 1434 (newer) history element that matches @var{pattern} (a regular | |
| 1435 expression). | |
| 1436 @end deffn | |
| 1437 | |
| 1438 @defun minibuffer-prompt | |
| 1439 This function returns the prompt string of the currently active | |
| 1440 minibuffer. If no minibuffer is active, it returns @code{nil}. | |
| 1441 @end defun | |
| 1442 | |
| 1443 @defun minibuffer-prompt-width | |
| 1444 This function returns the display width of the prompt string of the | |
| 1445 currently active minibuffer. If no minibuffer is active, it returns 0. | |
| 1446 @end defun | |
| 1447 | |
| 1448 @defvar minibuffer-setup-hook | |
| 1449 This is a normal hook that is run whenever the minibuffer is entered. | |
| 1450 @xref{Hooks}. | |
| 1451 @end defvar | |
| 1452 | |
| 1453 @defvar minibuffer-exit-hook | |
| 1454 This is a normal hook that is run whenever the minibuffer is exited. | |
| 1455 @xref{Hooks}. | |
| 1456 @end defvar | |
| 1457 | |
| 1458 @defvar minibuffer-help-form | |
| 1459 The current value of this variable is used to rebind @code{help-form} | |
| 1460 locally inside the minibuffer (@pxref{Help Functions}). | |
| 1461 @end defvar | |
| 1462 | |
| 1463 @defun active-minibuffer-window | |
| 1464 This function returns the currently active minibuffer window, or | |
| 1465 @code{nil} if none is currently active. | |
| 1466 @end defun | |
| 1467 | |
| 1468 @defun minibuffer-window &optional frame | |
| 1469 This function returns the minibuffer window used for frame @var{frame}. | |
| 1470 If @var{frame} is @code{nil}, that stands for the current frame. Note | |
| 1471 that the minibuffer window used by a frame need not be part of that | |
| 1472 frame---a frame that has no minibuffer of its own necessarily uses some | |
| 1473 other frame's minibuffer window. | |
| 1474 @end defun | |
| 1475 | |
| 1476 @c Emacs 19 feature | |
| 444 | 1477 @defun window-minibuffer-p &optional window |
| 428 | 1478 This function returns non-@code{nil} if @var{window} is a minibuffer window. |
| 1479 @end defun | |
| 1480 | |
| 1481 It is not correct to determine whether a given window is a minibuffer by | |
| 1482 comparing it with the result of @code{(minibuffer-window)}, because | |
| 1483 there can be more than one minibuffer window if there is more than one | |
| 1484 frame. | |
| 1485 | |
| 1486 @defun minibuffer-window-active-p window | |
| 1487 This function returns non-@code{nil} if @var{window}, assumed to be | |
| 1488 a minibuffer window, is currently active. | |
| 1489 @end defun | |
| 1490 | |
| 1491 @defvar minibuffer-scroll-window | |
| 1492 If the value of this variable is non-@code{nil}, it should be a window | |
| 1493 object. When the function @code{scroll-other-window} is called in the | |
| 1494 minibuffer, it scrolls this window. | |
| 1495 @end defvar | |
| 1496 | |
| 1497 Finally, some functions and variables deal with recursive minibuffers | |
| 1498 (@pxref{Recursive Editing}): | |
| 1499 | |
| 1500 @defun minibuffer-depth | |
| 1501 This function returns the current depth of activations of the | |
| 1502 minibuffer, a nonnegative integer. If no minibuffers are active, it | |
| 1503 returns zero. | |
| 1504 @end defun | |
| 1505 | |
| 1506 @defopt enable-recursive-minibuffers | |
| 1507 If this variable is non-@code{nil}, you can invoke commands (such as | |
| 434 | 1508 @code{find-file}) that use minibuffers even while the minibuffer window |
| 1509 is active. Such invocation produces a recursive editing level for a new | |
| 428 | 1510 minibuffer. The outer-level minibuffer is invisible while you are |
| 1511 editing the inner one. | |
| 1512 | |
| 1513 This variable only affects invoking the minibuffer while the | |
| 444 | 1514 minibuffer window is selected. If you switch windows while in the |
| 428 | 1515 minibuffer, you can always invoke minibuffer commands while some other |
| 1516 window is selected. | |
| 1517 @end defopt | |
| 1518 | |
| 1519 @c Emacs 19 feature | |
| 1520 In FSF Emacs 19, if a command name has a property | |
| 1521 @code{enable-recursive-minibuffers} that is non-@code{nil}, then the | |
| 1522 command can use the minibuffer to read arguments even if it is invoked | |
| 1523 from the minibuffer. The minibuffer command | |
| 1524 @code{next-matching-history-element} (normally @kbd{M-s} in the | |
| 1525 minibuffer) uses this feature. | |
| 1526 | |
| 1527 This is not implemented in XEmacs because it is a kludge. If you | |
| 1528 want to explicitly set the value of @code{enable-recursive-minibuffers} | |
| 1529 in this fashion, just use an evaluated interactive spec and bind | |
| 1530 @code{enable-recursive-minibuffers} while reading from the minibuffer. | |
| 1531 See the definition of @code{next-matching-history-element} in | |
| 434 | 1532 @file{lisp/minibuf.el}. |