[bpt/emacs.git] / lisp / emacs-lisp / map-ynp.el

;;; map-ynp.el --- general-purpose boolean question-asker

;; Copyright (C) 1991, 1992, 1993, 1994, 1995, 2000, 2001, 2002, 2003,
;;   2004, 2005, 2006, 2007, 2008 Free Software Foundation, Inc.

;; Author: Roland McGrath <roland@gnu.org>
;; Maintainer: FSF
;; Keywords: lisp, extensions

;; This file is part of GNU Emacs.

;; GNU Emacs is free software: you can redistribute it and/or modify
;; it under the terms of the GNU General Public License as published by
;; the Free Software Foundation, either version 3 of the License, or
;; (at your option) any later version.

;; GNU Emacs is distributed in the hope that it will be useful,
;; but WITHOUT ANY WARRANTY; without even the implied warranty of
;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
;; GNU General Public License for more details.

;; You should have received a copy of the GNU General Public License
;; along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.

;;; Commentary:

;; map-y-or-n-p is a general-purpose question-asking function.
;; It asks a series of y/n questions (a la y-or-n-p), and decides to
;; apply an action to each element of a list based on the answer.
;; The nice thing is that you also get some other possible answers
;; to use, reminiscent of query-replace: ! to answer y to all remaining
;; questions; ESC or q to answer n to all remaining questions; . to answer
;; y once and then n for the remainder; and you can get help with C-h.

;;; Code:

(defun map-y-or-n-p (prompter actor list &optional help action-alist
			      no-cursor-in-echo-area)
  "Ask a series of boolean questions.
Takes args PROMPTER ACTOR LIST, and optional args HELP and ACTION-ALIST.

LIST is a list of objects, or a function of no arguments to return the next
object or nil.

If PROMPTER is a string, the prompt is \(format PROMPTER OBJECT\).  If not
a string, PROMPTER is a function of one arg (an object from LIST), which
returns a string to be used as the prompt for that object.  If the return
value is not a string, it may be nil to ignore the object or non-nil to act
on the object without asking the user.

ACTOR is a function of one arg (an object from LIST),
which gets called with each object that the user answers `yes' for.

If HELP is given, it is a list (OBJECT OBJECTS ACTION),
where OBJECT is a string giving the singular noun for an elt of LIST;
OBJECTS is the plural noun for elts of LIST, and ACTION is a transitive
verb describing ACTOR.  The default is \(\"object\" \"objects\" \"act on\"\).

At the prompts, the user may enter y, Y, or SPC to act on that object;
n, N, or DEL to skip that object; ! to act on all following objects;
ESC or q to exit (skip all following objects); . (period) to act on the
current object and then exit; or \\[help-command] to get help.

If ACTION-ALIST is given, it is an alist (KEY FUNCTION HELP) of extra keys
that will be accepted.  KEY is a character; FUNCTION is a function of one
arg (an object from LIST); HELP is a string.  When the user hits KEY,
FUNCTION is called.  If it returns non-nil, the object is considered
\"acted upon\", and the next object from LIST is processed.  If it returns
nil, the prompt is repeated for the same object.

Final optional argument NO-CURSOR-IN-ECHO-AREA non-nil says not to set
`cursor-in-echo-area' while prompting.

This function uses `query-replace-map' to define the standard responses,
but not all of the responses which `query-replace' understands
are meaningful here.

Returns the number of actions taken."
  (let* ((actions 0)
	 user-keys mouse-event map prompt char elt tail def
	 ;; Non-nil means we should use mouse menus to ask.
	 use-menus
	 delayed-switch-frame
	 (next (if (or (and list (symbolp list))
		       (subrp list)
		       (byte-code-function-p list)
		       (and (consp list)
			    (eq (car list) 'lambda)))
		   (function (lambda ()
			       (setq elt (funcall list))))
		 (function (lambda ()
			     (if list
				 (progn
				   (setq elt (car list)
					 list (cdr list))
				   t)
			       nil))))))
    (if (and (listp last-nonmenu-event)
	     use-dialog-box)
	;; Make a list describing a dialog box.
	(let ((object (if help (capitalize (nth 0 help))))
	      (objects (if help (capitalize (nth 1 help))))
	      (action (if help (capitalize (nth 2 help)))))
	  (setq map `(("Yes" . act) ("No" . skip)
		      ,@(mapcar (lambda (elt)
				  (cons (with-syntax-table
					    text-mode-syntax-table
					  (capitalize (nth 2 elt)))
					(vector (nth 1 elt))))
				action-alist)
		      (,(if help (concat action " This But No More")
			  "Do This But No More") . act-and-exit)
		      (,(if help (concat action " All " objects)
			  "Do All") . automatic)
		      ("No For All" . exit))
		use-menus t
		mouse-event last-nonmenu-event))
      (setq user-keys (if action-alist
			  (concat (mapconcat (function
					      (lambda (elt)
						(key-description
						 (char-to-string (car elt)))))
					     action-alist ", ")
				  " ")
			"")
	    ;; Make a map that defines each user key as a vector containing
	    ;; its definition.
	    map (cons 'keymap
		      (append (mapcar (lambda (elt)
					(cons (car elt) (vector (nth 1 elt))))
				      action-alist)
			      query-replace-map))))
    (unwind-protect
	(progn
	  (if (stringp prompter)
	      (setq prompter `(lambda (object)
				(format ,prompter object))))
	  (while (funcall next)
	    (setq prompt (funcall prompter elt))
	    (cond ((stringp prompt)
		   ;; Prompt the user about this object.
		   (setq quit-flag nil)
		   (if use-menus
		       (setq def (or (x-popup-dialog (or mouse-event use-menus)
						     (cons prompt map))
				     'quit))
		     ;; Prompt in the echo area.
		     (let ((cursor-in-echo-area (not no-cursor-in-echo-area))
			   (message-log-max nil))
		       (message (apply 'propertize "%s(y, n, !, ., q, %sor %s) "
				       minibuffer-prompt-properties)
				prompt user-keys
				(key-description (vector help-char)))
		       (if minibuffer-auto-raise
			   (raise-frame (window-frame (minibuffer-window))))
		       (while (progn
				(setq char (read-event))
				;; If we get -1, from end of keyboard
				;; macro, try again.
                                (equal char -1)))
		       ;; Show the answer to the question.
		       (message "%s(y, n, !, ., q, %sor %s) %s"
				prompt user-keys
				(key-description (vector help-char))
				(single-key-description char)))
		     (setq def (lookup-key map (vector char))))
		   (cond ((eq def 'exit)
			  (setq next (function (lambda () nil))))
			 ((eq def 'act)
			  ;; Act on the object.
			  (funcall actor elt)
			  (setq actions (1+ actions)))
			 ((eq def 'skip)
			  ;; Skip the object.
			  )
			 ((eq def 'act-and-exit)
			  ;; Act on the object and then exit.
			  (funcall actor elt)
			  (setq actions (1+ actions)
				next (function (lambda () nil))))
			 ((eq def 'quit)
			  (setq quit-flag t)
			  (setq next `(lambda ()
					(setq next ',next)
					',elt)))
			 ((eq def 'automatic)
			  ;; Act on this and all following objects.
			  (if (funcall prompter elt)
			      (progn
				(funcall actor elt)
				(setq actions (1+ actions))))
			  (while (funcall next)
			    (if (funcall prompter elt)
				(progn
				  (funcall actor elt)
				  (setq actions (1+ actions))))))
			 ((eq def 'help)
			  (with-output-to-temp-buffer "*Help*"
			    (princ
			     (let ((object (if help (nth 0 help) "object"))
				   (objects (if help (nth 1 help) "objects"))
				   (action (if help (nth 2 help) "act on")))
			       (concat
				(format "Type SPC or `y' to %s the current %s;
DEL or `n' to skip the current %s;
RET or `q' to give up on the %s (skip all remaining %s);
C-g to quit (cancel the whole command);
! to %s all remaining %s;\n"
					action object object action objects action
					objects)
				(mapconcat (function
					    (lambda (elt)
					      (format "%s to %s"
						      (single-key-description
						       (nth 0 elt))
						      (nth 2 elt))))
					   action-alist
					   ";\n")
				(if action-alist ";\n")
				(format "or . (period) to %s \
the current %s and exit."
					action object))))
			    (save-excursion
			      (set-buffer standard-output)
			      (help-mode)))

			  (setq next `(lambda ()
				       (setq next ',next)
				       ',elt)))
			 ((vectorp def)
			  ;; A user-defined key.
			  (if (funcall (aref def 0) elt) ;Call its function.
			      ;; The function has eaten this object.
			      (setq actions (1+ actions))
			    ;; Regurgitated; try again.
			    (setq next `(lambda ()
					 (setq next ',next)
					 ',elt))))
			 ((and (consp char)
			       (eq (car char) 'switch-frame))
			  ;; switch-frame event.  Put it off until we're done.
			  (setq delayed-switch-frame char)
			  (setq next `(lambda ()
				       (setq next ',next)
				       ',elt)))
			 (t
			  ;; Random char.
			  (message "Type %s for help."
				   (key-description (vector help-char)))
			  (beep)
			  (sit-for 1)
			  (setq next `(lambda ()
				       (setq next ',next)
				       ',elt)))))
		  (prompt
		   (funcall actor elt)
		   (setq actions (1+ actions))))))
      (if delayed-switch-frame
	  (setq unread-command-events
		(cons delayed-switch-frame unread-command-events))))
    ;; Clear the last prompt from the minibuffer.
    (let ((message-log-max nil))
      (message ""))
    ;; Return the number of actions that were taken.
    actions))

;; arch-tag: 1d0a3201-a151-4c10-b231-4da47c9e6dc3
;;; map-ynp.el ends here
Commit	Line	Data
5e046f6d JB	1	;;; map-ynp.el --- general-purpose boolean question-asker
5e046f6d JB	2
d59c3137	3	;; Copyright (C) 1991, 1992, 1993, 1994, 1995, 2000, 2001, 2002, 2003,
8b72699e	4	;; 2004, 2005, 2006, 2007, 2008 Free Software Foundation, Inc.
5e046f6d JB	5
	6	;; Author: Roland McGrath <roland@gnu.org>
	7	;; Maintainer: FSF
	8	;; Keywords: lisp, extensions
	9
	10	;; This file is part of GNU Emacs.
	11
d6cba7ae	12	;; GNU Emacs is free software: you can redistribute it and/or modify
5e046f6d	13	;; it under the terms of the GNU General Public License as published by
d6cba7ae GM	14	;; the Free Software Foundation, either version 3 of the License, or
d6cba7ae GM	15	;; (at your option) any later version.
5e046f6d JB	16
	17	;; GNU Emacs is distributed in the hope that it will be useful,
	18	;; but WITHOUT ANY WARRANTY; without even the implied warranty of
	19	;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	20	;; GNU General Public License for more details.
	21
	22	;; You should have received a copy of the GNU General Public License
d6cba7ae	23	;; along with GNU Emacs. If not, see <http://www.gnu.org/licenses/>.
5e046f6d JB	24
	25	;;; Commentary:
	26
	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	;; apply 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.
	34
	35	;;; Code:
	36
	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.
	41
	42	LIST is a list of objects, or a function of no arguments to return the next
	43	object or nil.
	44
	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.
	50
	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.
	53
	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 \(\"object\" \"objects\" \"act on\"\).
	58
	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.
	63
	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.
	70
	71	Final optional argument NO-CURSOR-IN-ECHO-AREA non-nil says not to set
	72	`cursor-in-echo-area' while prompting.
	73
	74	This function uses `query-replace-map' to define the standard responses,
	75	but not all of the responses which `query-replace' understands
	76	are meaningful here.
	77
	78	Returns the number of actions taken."
	79	(let* ((actions 0)
	80	user-keys mouse-event map prompt char elt tail def
	81	;; Non-nil means we should use mouse menus to ask.
	82	use-menus
	83	delayed-switch-frame
	84	(next (if (or (and list (symbolp list))
	85	(subrp list)
	86	(byte-code-function-p list)
	87	(and (consp list)
88	(eq (car list) 'lambda)))
89	(function (lambda ()
90	(setq elt (funcall list))))
91	(function (lambda ()
92	(if list
93	(progn
94	(setq elt (car list)
95	list (cdr list))
96	t)
97	nil))))))
98	(if (and (listp last-nonmenu-event)
99	use-dialog-box)
100	;; Make a list describing a dialog box.
101	(let ((object (if help (capitalize (nth 0 help))))
102	(objects (if help (capitalize (nth 1 help))))
103	(action (if help (capitalize (nth 2 help)))))
369a47a4	104	(setq map `(("Yes" . act) ("No" . skip)
5e046f6d	105	,@(mapcar (lambda (elt)
369a47a4 RS	106	(cons (with-syntax-table
	107	text-mode-syntax-table
	108	(capitalize (nth 2 elt)))
5e046f6d	109	(vector (nth 1 elt))))
369a47a4 RS	110	action-alist)
	111	(,(if help (concat action " This But No More")
	112	"Do This But No More") . act-and-exit)
	113	(,(if help (concat action " All " objects)
	114	"Do All") . automatic)
	115	("No For All" . exit))
5e046f6d JB	116	use-menus t
	117	mouse-event last-nonmenu-event))
	118	(setq user-keys (if action-alist
	119	(concat (mapconcat (function
	120	(lambda (elt)
	121	(key-description
	122	(char-to-string (car elt)))))
	123	action-alist ", ")
	124	" ")
	125	"")
	126	;; Make a map that defines each user key as a vector containing
	127	;; its definition.
	128	map (cons 'keymap
	129	(append (mapcar (lambda (elt)
	130	(cons (car elt) (vector (nth 1 elt))))
	131	action-alist)
	132	query-replace-map))))
	133	(unwind-protect
	134	(progn
	135	(if (stringp prompter)
	136	(setq prompter `(lambda (object)
	137	(format ,prompter object))))
	138	(while (funcall next)
	139	(setq prompt (funcall prompter elt))
	140	(cond ((stringp prompt)
	141	;; Prompt the user about this object.
	142	(setq quit-flag nil)
	143	(if use-menus
	144	(setq def (or (x-popup-dialog (or mouse-event use-menus)
	145	(cons prompt map))
	146	'quit))
	147	;; Prompt in the echo area.
	148	(let ((cursor-in-echo-area (not no-cursor-in-echo-area))
	149	(message-log-max nil))
f7f2cc5d KS	150	(message (apply 'propertize "%s(y, n, !, ., q, %sor %s) "
f7f2cc5d KS	151	minibuffer-prompt-properties)
5e046f6d JB	152	prompt user-keys
	153	(key-description (vector help-char)))
	154	(if minibuffer-auto-raise
	155	(raise-frame (window-frame (minibuffer-window))))
	156	(while (progn
	157	(setq char (read-event))
	158	;; If we get -1, from end of keyboard
	159	;; macro, try again.
	160	(equal char -1)))
	161	;; Show the answer to the question.
	162	(message "%s(y, n, !, ., q, %sor %s) %s"
	163	prompt user-keys
	164	(key-description (vector help-char))
	165	(single-key-description char)))
	166	(setq def (lookup-key map (vector char))))
	167	(cond ((eq def 'exit)
	168	(setq next (function (lambda () nil))))
	169	((eq def 'act)
	170	;; Act on the object.
	171	(funcall actor elt)
	172	(setq actions (1+ actions)))
	173	((eq def 'skip)
	174	;; Skip the object.
	175	)
	176	((eq def 'act-and-exit)
	177	;; Act on the object and then exit.
	178	(funcall actor elt)
	179	(setq actions (1+ actions)
	180	next (function (lambda () nil))))
	181	((eq def 'quit)
	182	(setq quit-flag t)
	183	(setq next `(lambda ()
	184	(setq next ',next)
	185	',elt)))
	186	((eq def 'automatic)
	187	;; Act on this and all following objects.
	188	(if (funcall prompter elt)
	189	(progn
	190	(funcall actor elt)
	191	(setq actions (1+ actions))))
	192	(while (funcall next)
	193	(if (funcall prompter elt)
	194	(progn
	195	(funcall actor elt)
	196	(setq actions (1+ actions))))))
	197	((eq def 'help)
	198	(with-output-to-temp-buffer "Help"
	199	(princ
	200	(let ((object (if help (nth 0 help) "object"))
	201	(objects (if help (nth 1 help) "objects"))
	202	(action (if help (nth 2 help) "act on")))
	203	(concat
	204	(format "Type SPC or `y' to %s the current %s;
	205	DEL or `n' to skip the current %s;
90d0422a RS	206	RET or `q' to give up on the %s (skip all remaining %s);
90d0422a RS	207	C-g to quit (cancel the whole command);
5e046f6d	208	! to %s all remaining %s;\n"
90d0422a	209	action object object action objects action
5e046f6d JB	210	objects)
	211	(mapconcat (function
	212	(lambda (elt)
	213	(format "%s to %s"
	214	(single-key-description
	215	(nth 0 elt))
	216	(nth 2 elt))))
	217	action-alist
	218	";\n")
	219	(if action-alist ";\n")
	220	(format "or . (period) to %s \
	221	the current %s and exit."
	222	action object))))
	223	(save-excursion
	224	(set-buffer standard-output)
	225	(help-mode)))
	226
	227	(setq next `(lambda ()
	228	(setq next ',next)
	229	',elt)))
	230	((vectorp def)
	231	;; A user-defined key.
	232	(if (funcall (aref def 0) elt) ;Call its function.
	233	;; The function has eaten this object.
	234	(setq actions (1+ actions))
	235	;; Regurgitated; try again.
	236	(setq next `(lambda ()
	237	(setq next ',next)
	238	',elt))))
	239	((and (consp char)
	240	(eq (car char) 'switch-frame))
	241	;; switch-frame event. Put it off until we're done.
	242	(setq delayed-switch-frame char)
	243	(setq next `(lambda ()
	244	(setq next ',next)
	245	',elt)))
	246	(t
	247	;; Random char.
	248	(message "Type %s for help."
	249	(key-description (vector help-char)))
	250	(beep)
	251	(sit-for 1)
	252	(setq next `(lambda ()
	253	(setq next ',next)
	254	',elt)))))
	255	(prompt
	256	(funcall actor elt)
	257	(setq actions (1+ actions))))))
	258	(if delayed-switch-frame
	259	(setq unread-command-events
	260	(cons delayed-switch-frame unread-command-events))))
	261	;; Clear the last prompt from the minibuffer.
	262	(let ((message-log-max nil))
	263	(message ""))
	264	;; Return the number of actions that were taken.
	265	actions))
	266
cbee283d	267	;; arch-tag: 1d0a3201-a151-4c10-b231-4da47c9e6dc3
5e046f6d	268	;;; map-ynp.el ends here