1 ;;; map-ynp.el --- General-purpose boolean question-asker.
3 ;; Copyright (C) 1991, 1992, 1993, 1994, 1995 Free Software Foundation, Inc.
5 ;; Author: Roland McGrath <roland@gnu.ai.mit.edu>
6 ;; Keywords: lisp, extensions
8 ;; This file is part of GNU Emacs.
10 ;; GNU Emacs is free software; you can redistribute it and/or modify
11 ;; it under the terms of the GNU General Public License as published by
12 ;; the Free Software Foundation; either version 2, or (at your option)
15 ;; GNU Emacs is distributed in the hope that it will be useful,
16 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
17 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 ;; GNU General Public License for more details.
20 ;; You should have received a copy of the GNU General Public License
21 ;; along with GNU Emacs; see the file COPYING. If not, write to the
22 ;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
23 ;; Boston, MA 02111-1307, USA.
27 ;; map-y-or-n-p is a general-purpose question-asking function.
28 ;; It asks a series of y/n questions (a la y-or-n-p), and decides to
29 ;; applies an action to each element of a list based on the answer.
30 ;; The nice thing is that you also get some other possible answers
31 ;; to use, reminiscent of query-replace: ! to answer y to all remaining
32 ;; questions; ESC or q to answer n to all remaining questions; . to answer
33 ;; y once and then n for the remainder; and you can get help with C-h.
37 (defun map-y-or-n-p (prompter actor list
&optional help action-alist
38 no-cursor-in-echo-area
)
39 "Ask a series of boolean questions.
40 Takes args PROMPTER ACTOR LIST, and optional args HELP and ACTION-ALIST.
42 LIST is a list of objects, or a function of no arguments to return the next
45 If PROMPTER is a string, the prompt is \(format PROMPTER OBJECT\). If not
46 a string, PROMPTER is a function of one arg (an object from LIST), which
47 returns a string to be used as the prompt for that object. If the return
48 value is not a string, it may be nil to ignore the object or non-nil to act
49 on the object without asking the user.
51 ACTOR is a function of one arg (an object from LIST),
52 which gets called with each object that the user answers `yes' for.
54 If HELP is given, it is a list (OBJECT OBJECTS ACTION),
55 where OBJECT is a string giving the singular noun for an elt of LIST;
56 OBJECTS is the plural noun for elts of LIST, and ACTION is a transitive
57 verb describing ACTOR. The default is \(\"object\" \"objects\" \"act on\"\).
59 At the prompts, the user may enter y, Y, or SPC to act on that object;
60 n, N, or DEL to skip that object; ! to act on all following objects;
61 ESC or q to exit (skip all following objects); . (period) to act on the
62 current object and then exit; or \\[help-command] to get help.
64 If ACTION-ALIST is given, it is an alist (KEY FUNCTION HELP) of extra keys
65 that will be accepted. KEY is a character; FUNCTION is a function of one
66 arg (an object from LIST); HELP is a string. When the user hits KEY,
67 FUNCTION is called. If it returns non-nil, the object is considered
68 \"acted upon\", and the next object from LIST is processed. If it returns
69 nil, the prompt is repeated for the same object.
71 Final optional argument NO-CURSOR-IN-ECHO-AREA non-nil says not to set
72 `cursor-in-echo-area' while prompting.
74 This function uses `query-replace-map' to define the standard responses,
75 but not all of the responses which `query-replace' understands
78 Returns the number of actions taken."
80 user-keys mouse-event map prompt char elt tail def
81 ;; Non-nil means we should use mouse menus to ask.
84 (next (if (or (and list
(symbolp list
))
86 (byte-code-function-p list
)
88 (eq (car list
) 'lambda
)))
90 (setq elt
(funcall list
))))
98 (if (listp last-nonmenu-event
)
99 ;; Make a list describing a dialog box.
100 (let ((object (capitalize (nth 0 help
)))
101 (objects (capitalize (nth 1 help
)))
102 (action (capitalize (nth 2 help
))))
103 (setq map
(` (("Yes" . act
) ("No" . skip
) ("Quit" . exit
)
104 ((, (if help
(concat action
" " object
" And Quit")
105 "Do it and Quit")) . act-and-exit
)
106 ((, (if help
(concat action
" All " objects
)
107 "Do All")) . automatic
)
108 (,@ (mapcar (lambda (elt)
109 (cons (capitalize (nth 2 elt
))
110 (vector (nth 1 elt
))))
113 mouse-event last-nonmenu-event
))
114 (setq user-keys
(if action-alist
115 (concat (mapconcat (function
118 (char-to-string (car elt
)))))
122 ;; Make a map that defines each user key as a vector containing
125 (append (mapcar (lambda (elt)
126 (cons (car elt
) (vector (nth 1 elt
))))
128 query-replace-map
))))
131 (if (stringp prompter
)
132 (setq prompter
(` (lambda (object)
133 (format (, prompter
) object
)))))
134 (while (funcall next
)
135 (setq prompt
(funcall prompter elt
))
136 (cond ((stringp prompt
)
137 ;; Prompt the user about this object.
140 (setq def
(or (x-popup-dialog (or mouse-event use-menus
)
143 ;; Prompt in the echo area.
144 (let ((cursor-in-echo-area (not no-cursor-in-echo-area
))
145 (message-log-max nil
))
146 (message "%s(y, n, !, ., q, %sor %s) "
148 (key-description (vector help-char
)))
149 (if minibuffer-auto-raise
150 (raise-frame (window-frame (minibuffer-window))))
151 (setq char
(read-event))
152 ;; Show the answer to the question.
153 (message "%s(y, n, !, ., q, %sor %s) %s"
155 (key-description (vector help-char
))
156 (single-key-description char
)))
157 (setq def
(lookup-key map
(vector char
))))
158 (cond ((eq def
'exit
)
159 (setq next
(function (lambda () nil
))))
161 ;; Act on the object.
163 (setq actions
(1+ actions
)))
167 ((eq def
'act-and-exit
)
168 ;; Act on the object and then exit.
170 (setq actions
(1+ actions
)
171 next
(function (lambda () nil
))))
172 ((or (eq def
'quit
) (eq def
'exit-prefix
))
174 (setq next
(` (lambda ()
175 (setq next
'(, next
))
178 ;; Act on this and all following objects.
179 (if (funcall prompter elt
)
182 (setq actions
(1+ actions
))))
183 (while (funcall next
)
184 (if (funcall prompter elt
)
187 (setq actions
(1+ actions
))))))
189 (with-output-to-temp-buffer "*Help*"
191 (let ((object (if help
(nth 0 help
) "object"))
192 (objects (if help
(nth 1 help
) "objects"))
193 (action (if help
(nth 2 help
) "act on")))
195 (format "Type SPC or `y' to %s the current %s;
196 DEL or `n' to skip the current %s;
197 ! to %s all remaining %s;
198 ESC or `q' to exit;\n"
199 action object object action objects
)
207 (if action-alist
";\n")
208 (format "or . (period) to %s \
209 the current %s and exit."
212 (set-buffer standard-output
)
215 (setq next
(` (lambda ()
216 (setq next
'(, next
))
219 ;; A user-defined key.
220 (if (funcall (aref def
0) elt
) ;Call its function.
221 ;; The function has eaten this object.
222 (setq actions
(1+ actions
))
223 ;; Regurgitated; try again.
224 (setq next
(` (lambda ()
225 (setq next
'(, next
))
228 (eq (car char
) 'switch-frame
))
229 ;; switch-frame event. Put it off until we're done.
230 (setq delayed-switch-frame char
)
231 (setq next
(` (lambda ()
232 (setq next
'(, next
))
236 (message "Type %s for help."
237 (key-description (vector help-char
)))
240 (setq next
(` (lambda ()
241 (setq next
'(, next
))
245 (setq actions
(1+ actions
))))))
246 (if delayed-switch-frame
247 (setq unread-command-events
248 (cons delayed-switch-frame unread-command-events
))))
249 ;; Clear the last prompt from the minibuffer.
250 (let ((message-log-max nil
))
252 ;; Return the number of actions that were taken.
255 ;;; map-ynp.el ends here