]> code.delx.au - gnu-emacs/blobdiff - lisp/descr-text.el
(mac-charset-info-alist, mac-services-selection, mac-system-script-code):
[gnu-emacs] / lisp / descr-text.el
index ff38c21ed501e75221fb763a035a0844be107c10..e25d740b89bf5480ca9cc3436cfd19f33ebed00a 100644 (file)
@@ -1,9 +1,10 @@
 ;;; descr-text.el --- describe text mode
 
-;; Copyright (c) 1994, 1995, 1996, 2001, 02, 03 Free Software Foundation, Inc.
+;; Copyright (C) 1994, 1995, 1996, 2001, 2002, 2003, 2004,
+;;   2005 Free Software Foundation, Inc.
 
 ;; Author: Boris Goldowsky <boris@gnu.org>
-;; Keywords: faces
+;; Keywords: faces, i18n, Unicode, multilingual
 
 ;; This file is part of GNU Emacs.
 
@@ -19,8 +20,8 @@
 
 ;; 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.
+;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+;; Boston, MA 02110-1301, USA.
 
 ;;; Commentary:
 
@@ -28,7 +29,7 @@
 
 ;;; Code:
 
-(eval-when-compile (require 'button))
+(eval-when-compile (require 'button) (require 'quail))
 
 (defun describe-text-done ()
   "Delete the current window or bury the current buffer."
@@ -60,7 +61,7 @@ if that value is non-nil."
   (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))
+  (run-mode-hooks 'describe-text-mode-hook))
 
 ;;; Describe-Text Utilities.
 
@@ -99,26 +100,15 @@ if that value is non-nil."
 (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."
+The `category', `face' and `font-lock-face' properties are made
+into widget buttons that call `describe-text-category' or
+`describe-face' when pushed."
   ;; Sort the properties by the size of their value.
-  (dolist (elt (sort (let ((ret nil)
-                          (key nil)
-                          (val nil)
-                          (len nil))
+  (dolist (elt (sort (let (ret)
                       (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))
+                        (push (list (pop properties) (pop properties)) ret))
                       ret)
-                    (lambda (a b)
-                      (< (nth 2 a)
-                         (nth 2 b)))))
+                    (lambda (a b) (string< (nth 0 a) (nth 0 b)))))
     (let ((key (nth 0 elt))
          (value (nth 1 elt)))
       (widget-insert (propertize (format "  %-20s " key)
@@ -128,10 +118,15 @@ The `category' property is made into a widget button that call
                            :notify `(lambda (&rest ignore)
                                       (describe-text-category ',value))
                            (format "%S" value)))
-           ((widgetp value)
+            ((memq key '(face font-lock-face mouse-face))
+            (widget-create 'link
+                           :notify `(lambda (&rest ignore)
+                                      (describe-face ',value))
+                           (format "%S" value)))
+            ((widgetp value)
             (describe-text-widget value))
            (t
-            (widget-insert value))))
+            (describe-text-sexp value))))
     (widget-insert "\n")))
 \f
 ;;; Describe-Text Commands.
@@ -161,11 +156,12 @@ otherwise."
       (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"))
+      (let ((buffer (current-buffer))
+           (target-buffer "*Help*"))
+       (when (eq buffer (get-buffer target-buffer))
+         (setq target-buffer "*Help-2*"))
        (save-excursion
-         (with-output-to-temp-buffer "*Help*"
+         (with-output-to-temp-buffer target-buffer
            (set-buffer standard-output)
            (setq output-buffer (current-buffer))
            (widget-insert "Text content at position " (format "%d" pos) ":\n\n")
@@ -177,7 +173,6 @@ otherwise."
 (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))
@@ -219,221 +214,227 @@ otherwise."
        (widget-insert "There are text properties here:\n")
        (describe-property-list properties)))))
 \f
-;;; We cannot use the UnicodeData.txt file as such; it is not free.
-;;; We can turn that info a different format and release the result
-;;; as free data.  When that is done, we could reinstate the code below.
-;;; For the mean time, here is a dummy placeholder.
-;;;  -- rms
-(defun describe-char-unicode-data (char) nil)
-
-;;; (defcustom describe-char-unicodedata-file nil
-;;;   "Location of Unicode data file.
-;;; This is the UnicodeData.txt file from the Unicode consortium, used for
-;;; diagnostics.  If it is non-nil `describe-char-after' will print data
-;;; looked up from it.  This facility is mostly of use to people doing
-;;; multilingual development.
-
-;;; This is a fairly large file, not typically present on GNU systems.  At
-;;; the time of writing it is at
-;;; <URL:ftp://www.unicode.org/Public/UNIDATA/UnicodeData.txt>."
-;;;   :group 'mule
-;;;   :version "21.5"
-;;;   :type '(choice (const :tag "None" nil)
-;;;             file))
-
-;;; ;; We could convert the unidata file into a Lispy form once-for-all
-;;; ;; and distribute it for loading on demand.  It might be made more
-;;; ;; space-efficient by splitting strings word-wise and replacing them
-;;; ;; with lists of symbols interned in a private obarray, e.g.
-;;; ;; "LATIN SMALL LETTER A" => '(LATIN SMALL LETTER A).
-
-;;; ;; Fixme: Check whether this needs updating for Unicode 4.
-;;; (defun describe-char-unicode-data (char)
-;;;   "Return a list of Unicode data for unicode CHAR.
-;;; Each element is a list of a property description and the property value.
-;;; The list is null if CHAR isn't found in `describe-char-unicodedata-file'."
-;;;   (when describe-char-unicodedata-file
-;;;     (unless (file-exists-p describe-char-unicodedata-file)
-;;;       (error "`unicodedata-file' %s not found" describe-char-unicodedata-file))
-;;;     (save-excursion
-;;;       ;; Find file in fundamental mode to avoid, e.g. flyspell turned
-;;;       ;; on for .txt.  Don't use RAWFILE arg in case of DOS line endings.
-;;;       (set-buffer (let ((auto-mode-alist))
-;;;                (find-file-noselect describe-char-unicodedata-file)))
-;;;       (goto-char (point-min))
-;;;       (let ((hex (format "%04X" char))
-;;;        found first last)
-;;;    (if (re-search-forward (concat "^" hex) nil t)
-;;;        (setq found t)
-;;;      ;; It's not listed explicitly.  Look for ranges, e.g. CJK
-;;;      ;; ideographs, and check whether it's in one of them.
-;;;      (while (and (re-search-forward "^\\([^;]+\\);[^;]+First>;" nil t)
-;;;                  (>= char (setq first
-;;;                                 (string-to-number (match-string 1) 16)))
-;;;                  (progn
-;;;                    (forward-line 1)
-;;;                    (looking-at "^\\([^;]+\\);[^;]+Last>;")
-;;;                    (> char
-;;;                       (setq last
-;;;                             (string-to-number (match-string 1) 16))))))
-;;;      (if (and (>= char first)
-;;;               (<= char last))
-;;;          (setq found t)))
-;;;    (if found
-;;;        (let ((fields (mapcar (lambda (elt)
-;;;                                (if (> (length elt) 0)
-;;;                                    elt))
-;;;                              (cdr (split-string
-;;;                                    (buffer-substring
-;;;                                     (line-beginning-position)
-;;;                                     (line-end-position))
-;;;                                    ";")))))
-;;;          ;; The length depends on whether the last field was empty.
-;;;          (unless (or (= 13 (length fields))
-;;;                      (= 14 (length fields)))
-;;;            (error "Invalid contents in %s" describe-char-unicodedata-file))
-;;;          ;; The field names and values lists are slightly
-;;;          ;; modified from Mule-UCS unidata.el.
-;;;          (list
-;;;           (list "Name" (let ((name (nth 0 fields)))
-;;;                          ;; Check for <..., First>, <..., Last>
-;;;                          (if (string-match "\\`\\(<[^,]+\\)," name)
-;;;                              (concat (match-string 1 name) ">")
-;;;                            name)))
-;;;           (list "Category"
-;;;                 (cdr (assoc
-;;;                       (nth 1 fields)
-;;;                       '(("Lu" . "uppercase letter")
-;;;                         ("Ll" . "lowercase letter")
-;;;                         ("Lt" . "titlecase letter")
-;;;                         ("Mn" . "non-spacing mark")
-;;;                         ("Mc" . "spacing-combining mark")
-;;;                         ("Me" . "enclosing mark")
-;;;                         ("Nd" . "decimal digit")
-;;;                         ("Nl" . "letter number")
-;;;                         ("No" . "other number")
-;;;                         ("Zs" . "space separator")
-;;;                         ("Zl" . "line separator")
-;;;                         ("Zp" . "paragraph separator")
-;;;                         ("Cc" . "other control")
-;;;                         ("Cf" . "other format")
-;;;                         ("Cs" . "surrogate")
-;;;                         ("Co" . "private use")
-;;;                         ("Cn" . "not assigned")
-;;;                         ("Lm" . "modifier letter")
-;;;                         ("Lo" . "other letter")
-;;;                         ("Pc" . "connector punctuation")
-;;;                         ("Pd" . "dash punctuation")
-;;;                         ("Ps" . "open punctuation")
-;;;                         ("Pe" . "close punctuation")
-;;;                         ("Pi" . "initial-quotation punctuation")
-;;;                         ("Pf" . "final-quotation punctuation")
-;;;                         ("Po" . "other punctuation")
-;;;                         ("Sm" . "math symbol")
-;;;                         ("Sc" . "currency symbol")
-;;;                         ("Sk" . "modifier symbol")
-;;;                         ("So" . "other symbol")))))
-;;;           (list "Combining class"
-;;;                 (cdr (assoc
-;;;                       (string-to-number (nth 2 fields))
-;;;                       '((0 . "Spacing")
-;;;                         (1 . "Overlays and interior")
-;;;                         (7 . "Nuktas") 
-;;;                         (8 . "Hiragana/Katakana voicing marks")
-;;;                         (9 . "Viramas")
-;;;                         (10 . "Start of fixed position classes")
-;;;                         (199 . "End of fixed position classes")
-;;;                         (200 . "Below left attached")
-;;;                         (202 . "Below attached")
-;;;                         (204 . "Below right attached")
-;;;                         (208 . "Left attached (reordrant around \
-;;; single base character)")
-;;;                         (210 . "Right attached")
-;;;                         (212 . "Above left attached")
-;;;                         (214 . "Above attached")
-;;;                         (216 . "Above right attached")
-;;;                         (218 . "Below left")
-;;;                         (220 . "Below")
-;;;                         (222 . "Below right")
-;;;                         (224 . "Left (reordrant around single base \
-;;; character)")
-;;;                         (226 . "Right")
-;;;                         (228 . "Above left")
-;;;                         (230 . "Above")
-;;;                         (232 . "Above right")
-;;;                         (233 . "Double below")
-;;;                         (234 . "Double above")
-;;;                         (240 . "Below (iota subscript)")))))
-;;;           (list "Bidi category"
-;;;                 (cdr (assoc
-;;;                       (nth 3 fields)
-;;;                       '(("L" . "Left-to-Right")
-;;;                         ("LRE" . "Left-to-Right Embedding")
-;;;                         ("LRO" . "Left-to-Right Override")
-;;;                         ("R" . "Right-to-Left")
-;;;                         ("AL" . "Right-to-Left Arabic")
-;;;                         ("RLE" . "Right-to-Left Embedding")
-;;;                         ("RLO" . "Right-to-Left Override")
-;;;                         ("PDF" . "Pop Directional Format")
-;;;                         ("EN" . "European Number")
-;;;                         ("ES" . "European Number Separator")
-;;;                         ("ET" . "European Number Terminator")
-;;;                         ("AN" . "Arabic Number")
-;;;                         ("CS" . "Common Number Separator")
-;;;                         ("NSM" . "Non-Spacing Mark")
-;;;                         ("BN" . "Boundary Neutral")
-;;;                         ("B" . "Paragraph Separator")
-;;;                         ("S" . "Segment Separator")
-;;;                         ("WS" . "Whitespace")
-;;;                         ("ON" . "Other Neutrals")))))
-;;;           (list
-;;;            "Decomposition"
-;;;            (if (nth 4 fields)
-;;;                (let* ((parts (split-string (nth 4 fields)))
-;;;                       (info (car parts)))
-;;;                  (if (string-match "\\`<\\(.+\\)>\\'" info)
-;;;                      (setq info (match-string 1 info))
-;;;                    (setq info nil))
-;;;                  (if info (setq parts (cdr parts)))
-;;;                  ;; Maybe printing ? for unrepresentable unicodes
-;;;                  ;; here and below should be changed?
-;;;                  (setq parts (mapconcat
-;;;                               (lambda (arg)
-;;;                                 (string (or (decode-char
-;;;                                              'ucs
-;;;                                              (string-to-number arg 16))
-;;;                                             ??)))
-;;;                               parts " "))
-;;;                  (concat info parts))))
-;;;           (list "Decimal digit value"
-;;;                 (nth 5 fields))
-;;;           (list "Digit value"
-;;;                 (nth 6 fields))
-;;;           (list "Numeric value"
-;;;                 (nth 7 fields))
-;;;           (list "Mirrored"
-;;;                 (if (equal "Y" (nth 8 fields))
-;;;                     "yes"))
-;;;           (list "Old name" (nth 9 fields))
-;;;           (list "ISO 10646 comment" (nth 10 fields))
-;;;           (list "Uppercase" (and (nth 11 fields)
-;;;                                  (string (or (decode-char
-;;;                                               'ucs
-;;;                                               (string-to-number
-;;;                                                (nth 11 fields) 16))
-;;;                                              ??))))
-;;;           (list "Lowercase" (and (nth 12 fields)
-;;;                                  (string (or (decode-char
-;;;                                               'ucs
-;;;                                               (string-to-number
-;;;                                                (nth 12 fields) 16))
-;;;                                              ??))))
-;;;           (list "Titlecase" (and (nth 13 fields)
-;;;                                  (string (or (decode-char
-;;;                                               'ucs
-;;;                                               (string-to-number
-;;;                                                (nth 13 fields) 16))
-;;;                                              ??)))))))))))
+(defcustom describe-char-unicodedata-file nil
+  "Location of Unicode data file.
+This is the UnicodeData.txt file from the Unicode consortium, used for
+diagnostics.  If it is non-nil `describe-char' will print data
+looked up from it.  This facility is mostly of use to people doing
+multilingual development.
+
+This is a fairly large file, not typically present on GNU systems.  At
+the time of writing it is at
+<URL:http://www.unicode.org/Public/UNIDATA/UnicodeData.txt>."
+  :group 'mule
+  :version "22.1"
+  :type '(choice (const :tag "None" nil)
+                file))
+
+;; We could convert the unidata file into a Lispy form once-for-all
+;; and distribute it for loading on demand.  It might be made more
+;; space-efficient by splitting strings word-wise and replacing them
+;; with lists of symbols interned in a private obarray, e.g.
+;; "LATIN SMALL LETTER A" => '(LATIN SMALL LETTER A).
+
+;; Fixme: Check whether this needs updating for Unicode 4.
+(defun describe-char-unicode-data (char)
+  "Return a list of Unicode data for unicode CHAR.
+Each element is a list of a property description and the property value.
+The list is null if CHAR isn't found in `describe-char-unicodedata-file'."
+  (when describe-char-unicodedata-file
+    (unless (file-exists-p describe-char-unicodedata-file)
+      (error "`unicodedata-file' %s not found" describe-char-unicodedata-file))
+    (with-current-buffer
+       ;; Find file in fundamental mode to avoid, e.g. flyspell turned
+       ;; on for .txt.  Don't use RAWFILE arg in case of DOS line endings.
+       (let ((auto-mode-alist))
+         (find-file-noselect describe-char-unicodedata-file))
+      (goto-char (point-min))
+      (let ((hex (format "%04X" char))
+           found first last)
+       (if (re-search-forward (concat "^" hex) nil t)
+           (setq found t)
+         ;; It's not listed explicitly.  Look for ranges, e.g. CJK
+         ;; ideographs, and check whether it's in one of them.
+         (while (and (re-search-forward "^\\([^;]+\\);[^;]+First>;" nil t)
+                     (>= char (setq first
+                                    (string-to-number (match-string 1) 16)))
+                     (progn
+                       (forward-line 1)
+                       (looking-at "^\\([^;]+\\);[^;]+Last>;")
+                       (> char
+                          (setq last
+                                (string-to-number (match-string 1) 16))))))
+         (if (and (>= char first)
+                  (<= char last))
+             (setq found t)))
+       (if found
+           (let ((fields (mapcar (lambda (elt)
+                                   (if (> (length elt) 0)
+                                       elt))
+                                 (cdr (split-string
+                                       (buffer-substring
+                                        (line-beginning-position)
+                                        (line-end-position))
+                                       ";")))))
+             ;; The length depends on whether the last field was empty.
+             (unless (or (= 13 (length fields))
+                         (= 14 (length fields)))
+               (error "Invalid contents in %s" describe-char-unicodedata-file))
+             ;; The field names and values lists are slightly
+             ;; modified from Mule-UCS unidata.el.
+             (list
+              (list "Name" (let ((name (nth 0 fields)))
+                             ;; Check for <..., First>, <..., Last>
+                             (if (string-match "\\`\\(<[^,]+\\)," name)
+                                 (concat (match-string 1 name) ">")
+                               name)))
+              (list "Category"
+                    (cdr (assoc
+                          (nth 1 fields)
+                          '(("Lu" . "uppercase letter")
+                            ("Ll" . "lowercase letter")
+                            ("Lt" . "titlecase letter")
+                            ("Mn" . "non-spacing mark")
+                            ("Mc" . "spacing-combining mark")
+                            ("Me" . "enclosing mark")
+                            ("Nd" . "decimal digit")
+                            ("Nl" . "letter number")
+                            ("No" . "other number")
+                            ("Zs" . "space separator")
+                            ("Zl" . "line separator")
+                            ("Zp" . "paragraph separator")
+                            ("Cc" . "other control")
+                            ("Cf" . "other format")
+                            ("Cs" . "surrogate")
+                            ("Co" . "private use")
+                            ("Cn" . "not assigned")
+                            ("Lm" . "modifier letter")
+                            ("Lo" . "other letter")
+                            ("Pc" . "connector punctuation")
+                            ("Pd" . "dash punctuation")
+                            ("Ps" . "open punctuation")
+                            ("Pe" . "close punctuation")
+                            ("Pi" . "initial-quotation punctuation")
+                            ("Pf" . "final-quotation punctuation")
+                            ("Po" . "other punctuation")
+                            ("Sm" . "math symbol")
+                            ("Sc" . "currency symbol")
+                            ("Sk" . "modifier symbol")
+                            ("So" . "other symbol")))))
+              (list "Combining class"
+                    (cdr (assoc
+                          (string-to-number (nth 2 fields))
+                          '((0 . "Spacing")
+                            (1 . "Overlays and interior")
+                            (7 . "Nuktas")
+                            (8 . "Hiragana/Katakana voicing marks")
+                            (9 . "Viramas")
+                            (10 . "Start of fixed position classes")
+                            (199 . "End of fixed position classes")
+                            (200 . "Below left attached")
+                            (202 . "Below attached")
+                            (204 . "Below right attached")
+                            (208 . "Left attached (reordrant around \
+single base character)")
+                            (210 . "Right attached")
+                            (212 . "Above left attached")
+                            (214 . "Above attached")
+                            (216 . "Above right attached")
+                            (218 . "Below left")
+                            (220 . "Below")
+                            (222 . "Below right")
+                            (224 . "Left (reordrant around single base \
+character)")
+                            (226 . "Right")
+                            (228 . "Above left")
+                            (230 . "Above")
+                            (232 . "Above right")
+                            (233 . "Double below")
+                            (234 . "Double above")
+                            (240 . "Below (iota subscript)")))))
+              (list "Bidi category"
+                    (cdr (assoc
+                          (nth 3 fields)
+                          '(("L" . "Left-to-Right")
+                            ("LRE" . "Left-to-Right Embedding")
+                            ("LRO" . "Left-to-Right Override")
+                            ("R" . "Right-to-Left")
+                            ("AL" . "Right-to-Left Arabic")
+                            ("RLE" . "Right-to-Left Embedding")
+                            ("RLO" . "Right-to-Left Override")
+                            ("PDF" . "Pop Directional Format")
+                            ("EN" . "European Number")
+                            ("ES" . "European Number Separator")
+                            ("ET" . "European Number Terminator")
+                            ("AN" . "Arabic Number")
+                            ("CS" . "Common Number Separator")
+                            ("NSM" . "Non-Spacing Mark")
+                            ("BN" . "Boundary Neutral")
+                            ("B" . "Paragraph Separator")
+                            ("S" . "Segment Separator")
+                            ("WS" . "Whitespace")
+                            ("ON" . "Other Neutrals")))))
+              (list
+               "Decomposition"
+               (if (nth 4 fields)
+                   (let* ((parts (split-string (nth 4 fields)))
+                          (info (car parts)))
+                     (if (string-match "\\`<\\(.+\\)>\\'" info)
+                         (setq info (match-string 1 info))
+                       (setq info nil))
+                     (if info (setq parts (cdr parts)))
+                     ;; Maybe printing ? for unrepresentable unicodes
+                     ;; here and below should be changed?
+                     (setq parts (mapconcat
+                                  (lambda (arg)
+                                    (string (or (decode-char
+                                                 'ucs
+                                                 (string-to-number arg 16))
+                                                ??)))
+                                  parts " "))
+                     (concat info parts))))
+              (list "Decimal digit value"
+                    (nth 5 fields))
+              (list "Digit value"
+                    (nth 6 fields))
+              (list "Numeric value"
+                    (nth 7 fields))
+              (list "Mirrored"
+                    (if (equal "Y" (nth 8 fields))
+                        "yes"))
+              (list "Old name" (nth 9 fields))
+              (list "ISO 10646 comment" (nth 10 fields))
+              (list "Uppercase" (and (nth 11 fields)
+                                     (string (or (decode-char
+                                                  'ucs
+                                                  (string-to-number
+                                                   (nth 11 fields) 16))
+                                                 ??))))
+              (list "Lowercase" (and (nth 12 fields)
+                                     (string (or (decode-char
+                                                  'ucs
+                                                  (string-to-number
+                                                   (nth 12 fields) 16))
+                                                 ??))))
+              (list "Titlecase" (and (nth 13 fields)
+                                     (string (or (decode-char
+                                                  'ucs
+                                                  (string-to-number
+                                                   (nth 13 fields) 16))
+                                                 ??)))))))))))
+
+;; Return information about how CHAR is displayed at the buffer
+;; position POS.  If the selected frame is on a graphic display,
+;; return a cons (FONTNAME . GLYPH-CODE).  Otherwise, return a string
+;; describing the terminal codes for the character.
+(defun describe-char-display (pos char)
+  (if (display-graphic-p (selected-frame))
+      (internal-char-font pos char)
+    (let* ((coding (terminal-coding-system))
+          (encoded (encode-coding-char char coding)))
+      (if encoded
+         (encoded-string-description encoded coding)))))
+
 \f
 ;;;###autoload
 (defun describe-char (pos)
@@ -447,90 +448,172 @@ as well as widgets, buttons, overlays, and text properties."
       (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))))
+        (component-chars nil)
+        (display-table (or (window-display-table)
+                           buffer-display-table
+                           standard-display-table))
+        (disp-vector (and display-table (aref display-table char)))
         (multibyte-p enable-multibyte-characters)
+        (overlays (mapcar #'(lambda (o) (overlay-properties o))
+                          (overlays-at pos)))
         item-list max-width unicode)
-    (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))))
-
-      (if (or (< char 256)
-             (memq 'mule-utf-8 (find-coding-systems-region pos (1+ pos)))
-             (get-char-property pos 'untranslated-utf-8))
-         (setq unicode (or (get-char-property pos 'untranslated-utf-8)
-                           (encode-char char 'ucs))))
-      (setq item-list
-           `(("character"
-              ,(format "%s (0%o, %d, 0x%x%s)" (if (< char 256)
-                                                (single-key-description char)
-                                              (char-to-string char))
-                       char char char
-                       (if unicode
-                           (format ", U+%04X" unicode)
-                         "")))
-             ("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 (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"))))
-             ,@(let ((unicodedata (and unicode
-                                       (describe-char-unicode-data unicode))))
-                 (if unicodedata
-                     (cons (list "Unicode data" " ") unicodedata))))))
-    (setq max-width (apply #'max (mapcar #'(lambda (x) (length (car x)))
+
+    (if (or (< char 256)
+           (memq 'mule-utf-8 (find-coding-systems-region pos (1+ pos)))
+           (get-char-property pos 'untranslated-utf-8))
+       (setq unicode (or (get-char-property pos 'untranslated-utf-8)
+                         (encode-char char 'ucs))))
+    (setq item-list
+         `(("character"
+           ,(format "%s (0%o, %d, 0x%x%s)"
+                    (apply 'propertize (if (not multibyte-p)
+                                           (single-key-description char)
+                                         (if (< char 128)
+                                             (single-key-description char)
+                                           (string-to-multibyte
+                                            (char-to-string char))))
+                           (text-properties-at pos))
+                    char char char
+                    (if unicode
+                        (format ", U+%04X" unicode)
+                      "")))
+           ("charset"
+            ,`(widget-create 'link
+                             :notify (lambda (&rest ignore)
+                                       (describe-character-set ',charset))
+                             ,(symbol-name charset))
+            ,(format "(%s)" (charset-description charset)))
+           ("code point"
+            ,(let ((split (split-char char)))
+               `(widget-create
+                 'link
+                 :notify (lambda (&rest ignore)
+                           (list-charset-chars ',charset)
+                           (with-selected-window
+                               (get-buffer-window "*Character List*" 0)
+                             (goto-char (point-min))
+                              (forward-line 2) ;Skip the header.
+                              (let ((case-fold-search nil))
+                                (search-forward ,(char-to-string char)
+                                                nil t))))
+                 ,(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)))))
+           ("to input"
+            ,@(let ((key-list (and (eq input-method-function
+                                       'quail-input-method)
+                                   (quail-find-key char))))
+                (if (consp key-list)
+                    (list "type"
+                          (mapconcat #'(lambda (x) (concat "\"" x "\""))
+                                     key-list " or ")
+                          "with"
+                          `(widget-create
+                            'link
+                            :notify (lambda (&rest ignore)
+                                      (describe-input-method
+                                       ',current-input-method))
+                            ,(format "%s" current-input-method))))))
+           ("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)))))
+           ("display"
+            ,(cond
+              (disp-vector
+               (setq disp-vector (copy-sequence disp-vector))
+               (dotimes (i (length disp-vector))
+                 (setq char (aref disp-vector i))
+                 (aset disp-vector i
+                       (cons char (describe-char-display
+                                   pos (logand char #x7ffff)))))
+               (format "by display table entry [%s] (see below)"
+                       (mapconcat
+                        #'(lambda (x)
+                            (format "?%c" (logand (car x) #x7ffff)))
+                        disp-vector " ")))
+              (composition
+               (let ((from (car composition))
+                     (to (nth 1 composition))
+                     (next (1+ pos))
+                     (components (nth 2 composition))
+                     ch)
+                 (setcar composition
+                         (and (< from pos) (buffer-substring from pos)))
+                 (setcar (cdr composition)
+                         (and (< next to) (buffer-substring next to)))
+                 (dotimes (i (length components))
+                   (if (integerp (setq ch (aref components i)))
+                       (push (cons ch (describe-char-display pos ch))
+                             component-chars)))
+                 (setq component-chars (nreverse component-chars))
+                 (format "composed to form \"%s\" (see below)"
+                         (buffer-substring from to))))
+              (t
+               (let ((display (describe-char-display pos char)))
+                 (if (display-graphic-p (selected-frame))
+                     (if display
+                         (concat
+                          "by this font (glyph code)\n"
+                          (format "     %s (0x%02X)"
+                                  (car display) (cdr display)))
+                       "no font available")
+                   (if display
+                       (format "terminal code %s" display)
+                     "not encodable for terminal"))))))
+           ,@(let ((face
+                    (if (not (or disp-vector composition))
+                        (cond
+                         ((and show-trailing-whitespace
+                               (save-excursion (goto-char pos)
+                                               (looking-at "[ \t]+$")))
+                          'trailing-whitespace)
+                         ((and nobreak-char-display unicode (eq unicode '#xa0))
+                          'nobreak-space)
+                         ((and nobreak-char-display unicode (eq unicode '#xad))
+                          'escape-glyph)
+                         ((and (< char 32) (not (memq char '(9 10))))
+                          'escape-glyph)))))
+               (if face (list (list "hardcoded face"
+                                    `(widget-create
+                                      'link
+                                      :notify (lambda (&rest ignore)
+                                                (describe-face ',face))
+                                      ,(format "%s" face))))))
+           ,@(let ((unicodedata (and unicode
+                                     (describe-char-unicode-data unicode))))
+               (if unicodedata
+                   (cons (list "Unicode data" " ") unicodedata)))))
+    (setq max-width (apply #'max (mapcar #'(lambda (x)
+                                            (if (cadr x) (length (car x)) 0))
                                         item-list)))
-    (when (eq (current-buffer) (get-buffer "*Help*"))
-      (error "Can't describe char in Help buffer"))
     (with-output-to-temp-buffer "*Help*"
       (with-current-buffer standard-output
        (set-buffer-multibyte multibyte-p)
@@ -539,49 +622,108 @@ as well as widgets, buttons, overlays, and text properties."
            (when (cadr elt)
              (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))
+               (if (eq (car-safe clm) 'widget-create)
+                   (progn (insert " ") (eval clm))
+                 (when (>= (+ (current-column)
+                              (or (string-match "\n" clm)
+                                  (string-width clm))
+                              1)
+                           (window-width))
+                   (insert "\n")
+                   (indent-to (1+ max-width)))
+                 (insert " " clm)))
              (insert "\n"))))
+
+       (save-excursion
+         (goto-char (point-min))
+         (re-search-forward "character:[ \t\n]+")
+         (setq pos (point)))
+       (if overlays
+           (mapc #'(lambda (props)
+                     (let ((o (make-overlay pos (1+ pos))))
+                       (while props
+                         (overlay-put o (car props) (nth 1 props))
+                         (setq props (cddr props)))))
+                 overlays))
+
+       (when disp-vector
+         (insert
+          "\nThe display table entry is displayed by ")
+         (if (display-graphic-p (selected-frame))
+             (progn
+               (insert "these fonts (glyph codes):\n")
+               (dotimes (i (length disp-vector))
+                 (insert (logand (car (aref disp-vector i)) #x7ffff) ?:
+                         (propertize " " 'display '(space :align-to 5))
+                         (if (cdr (aref disp-vector i))
+                             (format "%s (0x%02X)" (cadr (aref disp-vector i))
+                                     (cddr (aref disp-vector i)))
+                           "-- no font --")
+                         "\n")
+                 (when (> (car (aref disp-vector i)) #x7ffff)
+                   (let* ((face-id (lsh (car (aref disp-vector i)) -19))
+                          (face (car (delq nil (mapcar (lambda (face)
+                                                         (and (eq (face-id face)
+                                                                  face-id) face))
+                                                       (face-list))))))
+                     (when face
+                       (insert (propertize " " 'display '(space :align-to 5))
+                               "face: ")
+                       (widget-create 'link
+                                      :notify `(lambda (&rest ignore)
+                                                 (describe-face ',face))
+                                      (format "%S" face))
+                       (insert "\n"))))))
+           (insert "these terminal codes:\n")
+           (dotimes (i (length disp-vector))
+             (insert (car (aref disp-vector i))
+                     (propertize " " 'display '(space :align-to 5))
+                     (or (cdr (aref disp-vector i)) "-- not encodable --")
+                     "\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))))))
+         (insert "\nComposed")
+         (if (car composition)
+             (if (cadr composition)
+                 (insert " with the surrounding characters \""
+                         (car composition) "\" and \""
+                         (cadr composition) "\"")
+               (insert " with the preceding character(s) \""
+                       (car composition) "\""))
+           (if (cadr composition)
+               (insert " with the following character(s) \""
+                       (cadr composition) "\"")))
+         (insert " by the rule:\n\t("
+                 (mapconcat (lambda (x)
+                              (format (if (consp x) "%S" "?%c") x))
+                            (nth 2 composition)
+                            " ")
+                 ")")
+         (insert  "\nThe component character(s) are displayed by ")
+         (if (display-graphic-p (selected-frame))
+             (progn
+               (insert "these fonts (glyph codes):")
+               (dolist (elt component-chars)
+                 (insert "\n " (car elt) ?:
+                         (propertize " " 'display '(space :align-to 5))
+                         (if (cdr elt)
+                             (format "%s (0x%02X)" (cadr elt) (cddr elt))
+                           "-- no font --"))))
+           (insert "these terminal codes:")
+           (dolist (elt component-chars)
+             (insert "\n  " (car elt) ":"
+                     (propertize " " 'display '(space :align-to 5))
+                     (or (cdr elt) "-- not encodable --"))))
+         (insert "\nSee the variable `reference-point-alist' for "
+                 "the meaning of the rule.\n"))
+
+       (describe-text-properties pos (current-buffer))
+       (describe-text-mode)))))
 
 (defalias 'describe-char-after 'describe-char)
-(make-obsolete 'describe-char-after 'describe-char "21.5")
+(make-obsolete 'describe-char-after 'describe-char "22.1")
 
 (provide 'descr-text)
 
-;;; arch-tag: fc55a498-f3e9-4312-b5bd-98cc02480af1
+;; arch-tag: fc55a498-f3e9-4312-b5bd-98cc02480af1
 ;;; descr-text.el ends here