[bpt/emacs.git] / lisp / descr-text.el

;;; descr-text.el --- describe text mode

;; Copyright (c) 1994, 1995, 1996, 2001, 2002 Free Software Foundation, Inc.

;; Author: Boris Goldowsky <boris@gnu.org>
;; Keywords: faces

;; 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 2, 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; see the file COPYING.  If not, write to the
;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
;; Boston, MA 02111-1307, USA.

;;; Commentary:

;;; Describe-Text Mode.

;;; Code:

(defun describe-text-done ()
  "Delete the current window or bury the current buffer."
  (interactive)
  (if (> (count-windows) 1)
      (delete-window)
    (bury-buffer)))

(defvar describe-text-mode-map 
  (let ((map (make-sparse-keymap)))
    (set-keymap-parent map widget-keymap)
    map)
  "Keymap for `describe-text-mode'.")
  
(defcustom describe-text-mode-hook nil
  "List of hook functions ran by `describe-text-mode'."
  :type 'hook)

(defun describe-text-mode ()
  "Major mode for buffers created by `describe-char'.

\\{describe-text-mode-map}
Entry to this mode calls the value of `describe-text-mode-hook'
if that value is non-nil."
  (kill-all-local-variables)
  (setq major-mode 'describe-text-mode
	mode-name "Describe-Text")
  (use-local-map describe-text-mode-map)
  (widget-setup)
  (add-hook 'change-major-mode-hook 'font-lock-defontify nil t)
  (run-hooks 'describe-text-mode-hook))

;;; Describe-Text Utilities.

(defun describe-text-widget (widget)
  "Insert text to describe WIDGET in the current buffer."
  (widget-create 'link
		 :notify `(lambda (&rest ignore)
			    (widget-browse ',widget))
		 (format "%S" (if (symbolp widget) 
				  widget
				(car widget))))
  (widget-insert " ")
  (widget-create 'info-link :tag "widget" "(widget)Top"))

(defun describe-text-sexp (sexp)
  "Insert a short description of SEXP in the current buffer."
  (let ((pp (condition-case signal
		(pp-to-string sexp)
	      (error (prin1-to-string signal)))))
    (when (string-match "\n\\'" pp)
      (setq pp (substring pp 0 (1- (length pp)))))
    (if (cond ((string-match "\n" pp)
	       nil)
	      ((> (length pp) (- (window-width) (current-column)))
	       nil)
	      (t t))
	(widget-insert pp)
      (widget-create 'push-button
		     :tag "show"
		     :action (lambda (widget &optional event)
			       (with-output-to-temp-buffer
				   "*Pp Eval Output*"
				 (princ (widget-get widget :value))))
		     pp))))

(defun describe-property-list (properties)
  "Insert a description of PROPERTIES in the current buffer.
PROPERTIES should be a list of overlay or text properties.
The `category' property is made into a widget button that call
`describe-text-category' when pushed."
  ;; Sort the properties by the size of their value.
  (dolist (elt (sort (let ((ret nil)
			   (key nil)
			   (val nil)
			   (len nil))
		       (while properties
			 (setq key (pop properties)
			       val (pop properties)
			       len 0)
			 (unless (or (eq key 'category)
				     (widgetp val))
			   (setq val (pp-to-string val)
				 len (length val)))
			 (push (list key val len) ret))
		       ret)
		     (lambda (a b)
		       (< (nth 2 a)
			  (nth 2 b)))))
    (let ((key (nth 0 elt))
	  (value (nth 1 elt)))
      (widget-insert (propertize (format "  %-20s " key)
				 'font-lock-face 'italic))
      (cond ((eq key 'category)
	     (widget-create 'link
			    :notify `(lambda (&rest ignore)
				       (describe-text-category ',value))
			    (format "%S" value)))
	    ((widgetp value)
	     (describe-text-widget value))
	    (t
	     (widget-insert value))))
    (widget-insert "\n")))
\f
;;; Describe-Text Commands.

(defun describe-text-category (category)
  "Describe a text property category."
  (interactive "S")
  (save-excursion
    (with-output-to-temp-buffer "*Help*"
      (set-buffer standard-output)
      (widget-insert "Category " (format "%S" category) ":\n\n")
      (describe-property-list (symbol-plist category))
      (describe-text-mode)
      (goto-char (point-min)))))

;;;###autoload
(defun describe-text-properties (pos &optional output-buffer)
  "Describe widgets, buttons, overlays and text properties at POS.
Interactively, describe them for the character after point.
If optional second argument OUTPUT-BUFFER is non-nil,
insert the output into that buffer, and don't initialize or clear it
otherwise."
  (interactive "d")
  (if (>= pos (point-max))
      (error "No character follows specified position"))
  (if output-buffer
      (describe-text-properties-1 pos output-buffer)
    (if (not (or (text-properties-at pos) (overlays-at pos)))
	(message "This is plain text.")
      (let ((buffer (current-buffer)))
	(when (eq buffer (get-buffer "*Help*"))
	  (error "Can't do self inspection"))
	(save-excursion
	  (with-output-to-temp-buffer "*Help*"
	    (set-buffer standard-output)
	    (setq output-buffer (current-buffer))
	    (widget-insert "Text content at position " (format "%d" pos) ":\n\n")
	    (with-current-buffer buffer
	      (describe-text-properties-1 pos output-buffer))
	    (describe-text-mode)
	    (goto-char (point-min))))))))

(defun describe-text-properties-1 (pos output-buffer)
  (let* ((properties (text-properties-at pos))
	 (overlays (overlays-at pos))
	 overlay
	 (wid-field (get-char-property pos 'field))
	 (wid-button (get-char-property pos 'button))
	 (wid-doc (get-char-property pos 'widget-doc))
	 ;; If button.el is not loaded, we have no buttons in the text.
	 (button (and (fboundp 'button-at) (button-at pos)))
	 (button-type (and button (button-type button)))
	 (button-label (and button (button-label button)))
	 (widget (or wid-field wid-button wid-doc)))
    (with-current-buffer output-buffer
      ;; Widgets
      (when (widgetp widget)
	(newline)
	(widget-insert (cond (wid-field "This is an editable text area")
			     (wid-button "This is an active area")
			     (wid-doc "This is documentation text")))
	(widget-insert " of a ")
	(describe-text-widget widget)
	(widget-insert ".\n\n"))
      ;; Buttons
      (when (and button (not (widgetp wid-button)))
	(newline)
	(widget-insert "Here is a " (format "%S" button-type) 
		       " button labeled `" button-label "'.\n\n"))
      ;; Overlays
      (when overlays
	(newline)
	(if (eq (length overlays) 1)
	    (widget-insert "There is an overlay here:\n")
	  (widget-insert "There are " (format "%d" (length overlays))
			 " overlays here:\n"))
	(dolist (overlay overlays)
	  (widget-insert " From " (format "%d" (overlay-start overlay)) 
			 " to " (format "%d" (overlay-end overlay)) "\n")
	  (describe-property-list (overlay-properties overlay)))
	(widget-insert "\n"))
      ;; Text properties
      (when properties
	(newline)
	(widget-insert "There are text properties here:\n")
	(describe-property-list properties)))))

;;;###autoload
(defun describe-char (pos)
  "Describe the character after POS (interactively, the character after point).
The information includes character code, charset and code points in it,
syntax, category, how the character is encoded in a file,
character composition information (if relevant),
as well as widgets, buttons, overlays, and text properties."
  (interactive "d")
  (if (>= pos (point-max))
      (error "No character follows specified position"))
  (let* ((char (char-after pos))
	 (charset (char-charset char))
	 (buffer (current-buffer))
	 (composition (find-composition pos nil nil t))
	 (composed (if composition (buffer-substring (car composition)
						     (nth 1 composition))))
	 (multibyte-p enable-multibyte-characters)
	 item-list max-width)
    (if (eq charset 'unknown)
	(setq item-list
	      `(("character"
		 ,(format "%s (0%o, %d, 0x%x) -- invalid character code"
			  (if (< char 256)
			      (single-key-description char)
			    (char-to-string char))
			  char char char))))
      (setq item-list
	    `(("character"
	       ,(format "%s (0%o, %d, 0x%x)" (if (< char 256)
						 (single-key-description char)
					       (char-to-string char))
			char char char))
	      ("charset"
	       ,(symbol-name charset)
	       ,(format "(%s)" (charset-description charset)))
	      ("code point"
	       ,(let ((split (split-char char)))
		  (if (= (charset-dimension charset) 1)
		      (format "%d" (nth 1 split))
		    (format "%d %d" (nth 1 split) (nth 2 split)))))
	      ("syntax"
 	       ,(let ((syntax (syntax-after pos)))
		  (with-temp-buffer
		    (internal-describe-syntax-value syntax)
		    (buffer-string))))
	      ("category"
	       ,@(let ((category-set (char-category-set char)))
		   (if (not category-set)
		       '("-- none --")
		     (mapcar #'(lambda (x) (format "%c:%s  "
						   x (category-docstring x)))
			     (category-set-mnemonics category-set)))))
	      ,@(let ((props (aref char-code-property-table char))
		      ps)
		  (when props
		    (while props
		      (push (format "%s:" (pop props)) ps)
		      (push (format "%s;" (pop props)) ps))
		    (list (cons "Properties" (nreverse ps)))))
	      ("buffer code"
	       ,(encoded-string-description
		 (string-as-unibyte (char-to-string char)) nil))
	      ("file code"
	       ,@(let* ((coding buffer-file-coding-system)
			(encoded (encode-coding-char char coding)))
		   (if encoded
		       (list (encoded-string-description encoded coding)
			     (format "(encoded by coding system %S)" coding))
		     (list "not encodable by coding system"
			   (symbol-name coding)))))
	      ,@(if (or (memq 'mule-utf-8
			  (find-coding-systems-region pos (1+ pos)))
			(get-char-property pos 'untranslated-utf-8))
		    (let ((uc (or (get-char-property pos 'untranslated-utf-8)
				  (encode-char char 'ucs))))
		      (if uc
			  (list (list "Unicode"
				      (format "%04X" uc))))))
	      ,(if (display-graphic-p (selected-frame))
		   (list "font" (or (internal-char-font pos)
				    "-- none --"))
		 (list "terminal code"
		       (let* ((coding (terminal-coding-system))
			      (encoded (encode-coding-char char coding)))
			 (if encoded
			     (encoded-string-description encoded coding)
			   "not encodable")))))))
    (setq max-width (apply #'max (mapcar #'(lambda (x) (length (car x)))
					 item-list)))
    (when (eq (current-buffer) (get-buffer "*Help*"))
      (error "Can't do self inspection"))
    (with-output-to-temp-buffer "*Help*"
      (with-current-buffer standard-output
	(set-buffer-multibyte multibyte-p)
	(let ((formatter (format "%%%ds:" max-width)))
	  (dolist (elt item-list)
	    (insert (format formatter (car elt)))
	    (dolist (clm (cdr elt))
	      (when (>= (+ (current-column)
			   (or (string-match "\n" clm)
			       (string-width clm)) 1)
			(frame-width))
		(insert "\n")
		(indent-to (1+ max-width)))
	      (insert " " clm))
	    (insert "\n")))
	(when composition
	  (insert "\nComposed with the "
		  (cond
		   ((eq pos (car composition)) "following ")
		   ((eq (1+ pos) (cadr composition)) "preceding ")
		   (t ""))
		  "character(s) `"
		  (cond
		   ((eq pos (car composition)) (substring composed 1))
		   ((eq (1+ pos) (cadr composition)) (substring composed 0 -1))
		   (t (concat (substring composed 0 (- pos (car composition)))
			      "' and `"
			      (substring composed (- (1+ pos) (car composition))))))
		    
		  "' to form `" composed "'")
	  (if (nth 3 composition)
	      (insert ".\n")
	    (insert "\nby the rule ("
		    (mapconcat (lambda (x)
				 (format (if (consp x) "%S" "?%c") x))
			       (nth 2 composition)
			       " ")
		    ").\n"
		    "See the variable `reference-point-alist' for "
		    "the meaning of the rule.\n")))

	(let ((output (current-buffer)))
	  (with-current-buffer buffer
	    (describe-text-properties pos output))
	  (describe-text-mode))))))

(provide 'descr-text)

;;; descr-text.el ends here
Commit	Line	Data
dcb90b5f	1	;;; descr-text.el --- describe text mode
2a1e884e RS	2
	3	;; Copyright (c) 1994, 1995, 1996, 2001, 2002 Free Software Foundation, Inc.
	4
	5	;; Author: Boris Goldowsky <boris@gnu.org>
	6	;; Keywords: faces
	7
	8	;; This file is part of GNU Emacs.
	9
	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)
	13	;; any later version.
	14
	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.
	19
	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.
	24
	25	;;; Commentary:
	26
	27	;;; Describe-Text Mode.
	28
	29	;;; Code:
	30
	31	(defun describe-text-done ()
	32	"Delete the current window or bury the current buffer."
	33	(interactive)
	34	(if (> (count-windows) 1)
	35	(delete-window)
	36	(bury-buffer)))
	37
	38	(defvar describe-text-mode-map
	39	(let ((map (make-sparse-keymap)))
	40	(set-keymap-parent map widget-keymap)
	41	map)
	42	"Keymap for `describe-text-mode'.")
	43
	44	(defcustom describe-text-mode-hook nil
	45	"List of hook functions ran by `describe-text-mode'."
	46	:type 'hook)
	47
	48	(defun describe-text-mode ()
4adb7c09	49	"Major mode for buffers created by `describe-char'.
2a1e884e RS	50
	51	\\{describe-text-mode-map}
	52	Entry to this mode calls the value of `describe-text-mode-hook'
	53	if that value is non-nil."
	54	(kill-all-local-variables)
	55	(setq major-mode 'describe-text-mode
	56	mode-name "Describe-Text")
	57	(use-local-map describe-text-mode-map)
	58	(widget-setup)
f0397cde	59	(add-hook 'change-major-mode-hook 'font-lock-defontify nil t)
2a1e884e RS	60	(run-hooks 'describe-text-mode-hook))
	61
	62	;;; Describe-Text Utilities.
	63
	64	(defun describe-text-widget (widget)
	65	"Insert text to describe WIDGET in the current buffer."
	66	(widget-create 'link
	67	:notify `(lambda (&rest ignore)
	68	(widget-browse ',widget))
	69	(format "%S" (if (symbolp widget)
	70	widget
	71	(car widget))))
	72	(widget-insert " ")
	73	(widget-create 'info-link :tag "widget" "(widget)Top"))
	74
	75	(defun describe-text-sexp (sexp)
	76	"Insert a short description of SEXP in the current buffer."
	77	(let ((pp (condition-case signal
	78	(pp-to-string sexp)
	79	(error (prin1-to-string signal)))))
	80	(when (string-match "\n\\'" pp)
	81	(setq pp (substring pp 0 (1- (length pp)))))
	82	(if (cond ((string-match "\n" pp)
	83	nil)
	84	((> (length pp) (- (window-width) (current-column)))
	85	nil)
	86	(t t))
	87	(widget-insert pp)
	88	(widget-create 'push-button
	89	:tag "show"
	90	:action (lambda (widget &optional event)
	91	(with-output-to-temp-buffer
	92	"Pp Eval Output"
	93	(princ (widget-get widget :value))))
	94	pp))))
2a1e884e	95
4adb7c09	96	(defun describe-property-list (properties)
2a1e884e RS	97	"Insert a description of PROPERTIES in the current buffer.
2a1e884e RS	98	PROPERTIES should be a list of overlay or text properties.
c1a1535a	99	The `category' property is made into a widget button that call
2a1e884e	100	`describe-text-category' when pushed."
e2fa2f6e CW	101	;; Sort the properties by the size of their value.
	102	(dolist (elt (sort (let ((ret nil)
	103	(key nil)
	104	(val nil)
	105	(len nil))
	106	(while properties
	107	(setq key (pop properties)
	108	val (pop properties)
	109	len 0)
	110	(unless (or (eq key 'category)
	111	(widgetp val))
	112	(setq val (pp-to-string val)
	113	len (length val)))
	114	(push (list key val len) ret))
	115	ret)
	116	(lambda (a b)
	117	(< (nth 2 a)
	118	(nth 2 b)))))
	119	(let ((key (nth 0 elt))
	120	(value (nth 1 elt)))
c1a1535a	121	(widget-insert (propertize (format " %-20s " key)
e2fa2f6e	122	'font-lock-face 'italic))
2a1e884e	123	(cond ((eq key 'category)
c1a1535a	124	(widget-create 'link
2a1e884e RS	125	:notify `(lambda (&rest ignore)
	126	(describe-text-category ',value))
	127	(format "%S" value)))
	128	((widgetp value)
	129	(describe-text-widget value))
	130	(t
e2fa2f6e CW	131	(widget-insert value))))
e2fa2f6e CW	132	(widget-insert "\n")))
2a1e884e RS	133	\f
	134	;;; Describe-Text Commands.
	135
	136	(defun describe-text-category (category)
	137	"Describe a text property category."
	138	(interactive "S")
2a1e884e	139	(save-excursion
ca9088e7 SM	140	(with-output-to-temp-buffer "Help"
ca9088e7 SM	141	(set-buffer standard-output)
2a1e884e	142	(widget-insert "Category " (format "%S" category) ":\n\n")
4adb7c09	143	(describe-property-list (symbol-plist category))
2a1e884e RS	144	(describe-text-mode)
	145	(goto-char (point-min)))))
	146
	147	;;;###autoload
4adb7c09 RS	148	(defun describe-text-properties (pos &optional output-buffer)
	149	"Describe widgets, buttons, overlays and text properties at POS.
	150	Interactively, describe them for the character after point.
	151	If optional second argument OUTPUT-BUFFER is non-nil,
	152	insert the output into that buffer, and don't initialize or clear it
	153	otherwise."
2a1e884e	154	(interactive "d")
4adb7c09 RS	155	(if (>= pos (point-max))
	156	(error "No character follows specified position"))
	157	(if output-buffer
	158	(describe-text-properties-1 pos output-buffer)
	159	(if (not (or (text-properties-at pos) (overlays-at pos)))
	160	(message "This is plain text.")
4adb7c09	161	(let ((buffer (current-buffer)))
ca9088e7 SM	162	(when (eq buffer (get-buffer "Help"))
ca9088e7 SM	163	(error "Can't do self inspection"))
4adb7c09	164	(save-excursion
ca9088e7 SM	165	(with-output-to-temp-buffer "Help"
ca9088e7 SM	166	(set-buffer standard-output)
4adb7c09 RS	167	(setq output-buffer (current-buffer))
	168	(widget-insert "Text content at position " (format "%d" pos) ":\n\n")
	169	(with-current-buffer buffer
	170	(describe-text-properties-1 pos output-buffer))
	171	(describe-text-mode)
	172	(goto-char (point-min))))))))
	173
	174	(defun describe-text-properties-1 (pos output-buffer)
2a1e884e RS	175	(let* ((properties (text-properties-at pos))
	176	(overlays (overlays-at pos))
	177	overlay
	178	(wid-field (get-char-property pos 'field))
	179	(wid-button (get-char-property pos 'button))
	180	(wid-doc (get-char-property pos 'widget-doc))
	181	;; If button.el is not loaded, we have no buttons in the text.
	182	(button (and (fboundp 'button-at) (button-at pos)))
	183	(button-type (and button (button-type button)))
	184	(button-label (and button (button-label button)))
	185	(widget (or wid-field wid-button wid-doc)))
4adb7c09 RS	186	(with-current-buffer output-buffer
	187	;; Widgets
	188	(when (widgetp widget)
	189	(newline)
	190	(widget-insert (cond (wid-field "This is an editable text area")
	191	(wid-button "This is an active area")
	192	(wid-doc "This is documentation text")))
	193	(widget-insert " of a ")
	194	(describe-text-widget widget)
	195	(widget-insert ".\n\n"))
	196	;; Buttons
	197	(when (and button (not (widgetp wid-button)))
	198	(newline)
	199	(widget-insert "Here is a " (format "%S" button-type)
	200	" button labeled `" button-label "'.\n\n"))
	201	;; Overlays
	202	(when overlays
	203	(newline)
	204	(if (eq (length overlays) 1)
	205	(widget-insert "There is an overlay here:\n")
	206	(widget-insert "There are " (format "%d" (length overlays))
	207	" overlays here:\n"))
	208	(dolist (overlay overlays)
	209	(widget-insert " From " (format "%d" (overlay-start overlay))
	210	" to " (format "%d" (overlay-end overlay)) "\n")
	211	(describe-property-list (overlay-properties overlay)))
	212	(widget-insert "\n"))
	213	;; Text properties
	214	(when properties
	215	(newline)
	216	(widget-insert "There are text properties here:\n")
	217	(describe-property-list properties)))))
	218
	219	;;;###autoload
	220	(defun describe-char (pos)
	221	"Describe the character after POS (interactively, the character after point).
	222	The information includes character code, charset and code points in it,
	223	syntax, category, how the character is encoded in a file,
	224	character composition information (if relevant),
	225	as well as widgets, buttons, overlays, and text properties."
	226	(interactive "d")
4adb7c09 RS	227	(if (>= pos (point-max))
	228	(error "No character follows specified position"))
	229	(let* ((char (char-after pos))
	230	(charset (char-charset char))
	231	(buffer (current-buffer))
ca9088e7	232	(composition (find-composition pos nil nil t))
4adb7c09 RS	233	(composed (if composition (buffer-substring (car composition)
	234	(nth 1 composition))))
	235	(multibyte-p enable-multibyte-characters)
	236	item-list max-width)
	237	(if (eq charset 'unknown)
	238	(setq item-list
	239	`(("character"
	240	,(format "%s (0%o, %d, 0x%x) -- invalid character code"
	241	(if (< char 256)
	242	(single-key-description char)
	243	(char-to-string char))
	244	char char char))))
	245	(setq item-list
	246	`(("character"
	247	,(format "%s (0%o, %d, 0x%x)" (if (< char 256)
	248	(single-key-description char)
	249	(char-to-string char))
	250	char char char))
	251	("charset"
	252	,(symbol-name charset)
	253	,(format "(%s)" (charset-description charset)))
	254	("code point"
	255	,(let ((split (split-char char)))
	256	(if (= (charset-dimension charset) 1)
	257	(format "%d" (nth 1 split))
	258	(format "%d %d" (nth 1 split) (nth 2 split)))))
	259	("syntax"
ca9088e7	260	,(let ((syntax (syntax-after pos)))
4adb7c09	261	(with-temp-buffer
ca9088e7	262	(internal-describe-syntax-value syntax)
4adb7c09 RS	263	(buffer-string))))
	264	("category"
	265	,@(let ((category-set (char-category-set char)))
	266	(if (not category-set)
	267	'("-- none --")
	268	(mapcar #'(lambda (x) (format "%c:%s "
	269	x (category-docstring x)))
	270	(category-set-mnemonics category-set)))))
	271	,@(let ((props (aref char-code-property-table char))
	272	ps)
	273	(when props
	274	(while props
	275	(push (format "%s:" (pop props)) ps)
	276	(push (format "%s;" (pop props)) ps))
	277	(list (cons "Properties" (nreverse ps)))))
	278	("buffer code"
	279	,(encoded-string-description
	280	(string-as-unibyte (char-to-string char)) nil))
	281	("file code"
	282	,@(let* ((coding buffer-file-coding-system)
	283	(encoded (encode-coding-char char coding)))
	284	(if encoded
	285	(list (encoded-string-description encoded coding)
	286	(format "(encoded by coding system %S)" coding))
	287	(list "not encodable by coding system"
	288	(symbol-name coding)))))
	289	,@(if (or (memq 'mule-utf-8
ca9088e7 SM	290	(find-coding-systems-region pos (1+ pos)))
	291	(get-char-property pos 'untranslated-utf-8))
	292	(let ((uc (or (get-char-property pos 'untranslated-utf-8)
	293	(encode-char char 'ucs))))
4adb7c09 RS	294	(if uc
	295	(list (list "Unicode"
	296	(format "%04X" uc))))))
	297	,(if (display-graphic-p (selected-frame))
ca9088e7	298	(list "font" (or (internal-char-font pos)
4adb7c09 RS	299	"-- none --"))
	300	(list "terminal code"
	301	(let* ((coding (terminal-coding-system))
	302	(encoded (encode-coding-char char coding)))
	303	(if encoded
	304	(encoded-string-description encoded coding)
	305	"not encodable")))))))
	306	(setq max-width (apply #'max (mapcar #'(lambda (x) (length (car x)))
	307	item-list)))
ca9088e7 SM	308	(when (eq (current-buffer) (get-buffer "Help"))
ca9088e7 SM	309	(error "Can't do self inspection"))
4adb7c09	310	(with-output-to-temp-buffer "Help"
ca9088e7	311	(with-current-buffer standard-output
4adb7c09 RS	312	(set-buffer-multibyte multibyte-p)
	313	(let ((formatter (format "%%%ds:" max-width)))
	314	(dolist (elt item-list)
	315	(insert (format formatter (car elt)))
	316	(dolist (clm (cdr elt))
	317	(when (>= (+ (current-column)
	318	(or (string-match "\n" clm)
	319	(string-width clm)) 1)
	320	(frame-width))
	321	(insert "\n")
	322	(indent-to (1+ max-width)))
	323	(insert " " clm))
	324	(insert "\n")))
	325	(when composition
ca9088e7 SM	326	(insert "\nComposed with the "
	327	(cond
	328	((eq pos (car composition)) "following ")
	329	((eq (1+ pos) (cadr composition)) "preceding ")
	330	(t ""))
	331	"character(s) `"
	332	(cond
	333	((eq pos (car composition)) (substring composed 1))
	334	((eq (1+ pos) (cadr composition)) (substring composed 0 -1))
	335	(t (concat (substring composed 0 (- pos (car composition)))
	336	"' and `"
	337	(substring composed (- (1+ pos) (car composition))))))
	338
	339	"' to form `" composed "'")
4adb7c09 RS	340	(if (nth 3 composition)
	341	(insert ".\n")
	342	(insert "\nby the rule ("
	343	(mapconcat (lambda (x)
	344	(format (if (consp x) "%S" "?%c") x))
	345	(nth 2 composition)
	346	" ")
	347	").\n"
	348	"See the variable `reference-point-alist' for "
	349	"the meaning of the rule.\n")))
	350
	351	(let ((output (current-buffer)))
	352	(with-current-buffer buffer
	353	(describe-text-properties pos output))
	354	(describe-text-mode))))))
2a1e884e	355
288395a7 CW	356	(provide 'descr-text)
288395a7 CW	357
2a1e884e	358	;;; descr-text.el ends here