* org-agenda.el (org-agenda-restore-windows-after-quit): Fix typo in docstring.
[bpt/emacs.git] / lisp / descr-text.el
index 0194b71..b559a13 100644 (file)
@@ -1,7 +1,7 @@
 ;;; descr-text.el --- describe text mode
 
 ;; Copyright (C) 1994, 1995, 1996, 2001, 2002, 2003, 2004,
-;;   2005, 2006, 2007, 2008 Free Software Foundation, Inc.
+;;   2005, 2006, 2007, 2008, 2009 Free Software Foundation, Inc.
 
 ;; Author: Boris Goldowsky <boris@gnu.org>
 ;; Maintainer: FSF
@@ -9,10 +9,10 @@
 
 ;; This file is part of GNU Emacs.
 
-;; GNU Emacs is free software; you can redistribute it and/or modify
+;; 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, or (at your option)
-;; any later version.
+;; 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
@@ -20,9 +20,7 @@
 ;; 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., 51 Franklin Street, Fifth Floor,
-;; Boston, MA 02110-1301, USA.
+;; along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.
 
 ;;; Commentary:
 
   (let ((pp (condition-case signal
                (pp-to-string sexp)
              (error (prin1-to-string signal)))))
-    (when (string-match "\n\\'" pp)
+    (when (string-match-p "\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))
+
+    (if (and (not (string-match-p "\n" pp))
+            (<= (length pp) (- (window-width) (current-column))))
        (insert pp)
       (insert-text-button
        "[Show]" 'action `(lambda (&rest ignore)
-                       (with-output-to-temp-buffer
-                           "*Pp Eval Output*"
-                         (princ ',pp)))
+                          (with-output-to-temp-buffer
+                              "*Pp Eval Output*"
+                            (princ ',pp)))
        'help-echo "mouse-2, RET: pretty print value in another buffer"))))
 
 (defun describe-property-list (properties)
@@ -88,6 +84,7 @@ into help buttons that call `describe-text-category' or
              (symbol-name value)
              'action `(lambda (&rest ignore)
                         (describe-text-category ',value))
+             'follow-link t
              'help-echo "mouse-2, RET: describe this category"))
             ((memq key '(face font-lock-face mouse-face))
             (insert-text-button
@@ -183,6 +180,29 @@ otherwise."
        (insert "There are text properties here:\n")
        (describe-property-list properties)))))
 \f
+(defcustom describe-char-unidata-list
+  '(name old-name general-category decomposition)
+  "List of Unicode-based character property names shown by `describe-char'."
+  :group 'mule
+  :version "23.1"
+  :type '(choice (const :tag "All properties" t)
+          (set
+           (const :tag "Unicode Name" name)
+           (const :tag "Unicode old name" old-name)
+           (const :tag "Unicode general category " general-category)
+           (const :tag "Unicode canonical combining class"
+                  canonical-combining-class)
+           (const :tag "Unicode bidi class" bidi-class)
+           (const :tag "Unicode decomposition mapping" decomposition)
+           (const :tag "Unicode decimal digit value" decimal-digit-value)
+           (const :tag "Unicode digit value" digit-value)
+           (const :tag "Unicode numeric value" numeric-value)
+           (const :tag "Unicode mirrored" mirrored)
+           (const :tag "Unicode ISO 10646 comment" iso-10646-comment)
+           (const :tag "Unicode simple uppercase mapping" uppercase)
+           (const :tag "Unicode simple lowercase mapping" lowercase)
+           (const :tag "Unicode simple titlecase mapping" titlecase))))
+
 (defcustom describe-char-unicodedata-file nil
   "Location of Unicode data file.
 This is the UnicodeData.txt file from the Unicode Consortium, used for
@@ -198,17 +218,11 @@ At the time of writing it is at the URL
   :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'."
+The list is null if CHAR isn't found in `describe-char-unicodedata-file'.
+This function is semi-obsolete.  Use `get-char-code-property'."
   (when describe-char-unicodedata-file
     (unless (file-exists-p describe-char-unicodedata-file)
       (error "`unicodedata-file' %s not found" describe-char-unicodedata-file))
@@ -257,91 +271,20 @@ The list is null if CHAR isn't found in `describe-char-unicodedata-file'."
                                  (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")))))
+                    (let ((val (nth 1 fields)))
+                      (or (char-code-property-description
+                           'general-category (intern val))
+                          val)))
               (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)")))))
+                    (let ((val (nth 1 fields)))
+                      (or (char-code-property-description
+                           'canonical-combining-class (intern val))
+                          val)))
               (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")))))
+                    (let ((val (nth 1 fields)))
+                      (or (char-code-property-description
+                           'bidi-class (intern val))
+                          val)))
               (list
                "Decomposition"
                (if (nth 4 fields)
@@ -351,14 +294,9 @@ character)")
                          (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))
-                                                ??)))
+                                    (string (string-to-number arg 16)))
                                   parts " "))
                      (concat info parts))))
               (list "Decimal digit value"
@@ -373,37 +311,64 @@ character)")
               (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))
-                                                 ??))))
+                                     (string (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))
-                                                 ??))))
+                                     (string (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))
-                                                 ??)))))))))))
+                                     (string (string-to-number
+                                              (nth 13 fields) 16)))))))))))
+
+;; Not defined on builds without X, but behind display-graphic-p.
+(declare-function internal-char-font "fontset.c" (position &optional ch))
 
 ;; 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.
+;; return a string "FONT-DRIVER:FONT-NAME (GLYPH-CODE)" where:
+;;   FONT-DRIVER is the font-driver name,
+;;   FONT-NAME is the font name,
+;;   GLYPH-CODE is a hexadigit string representing the glyph-ID.
+;; 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)))
+      (let ((char-font-info (internal-char-font pos char)))
+       (if char-font-info
+           (let ((type (font-get (car char-font-info) :type))
+                 (name (font-xlfd-name (car char-font-info)))
+                 (code (cdr char-font-info)))
+              (if (integerp code)
+                  (format "%s:%s (#x%02X)" type name code)
+                (format "%s:%s (#x%04X%04X)"
+                        type name (car code) (cdr code))))))
+    (let* ((charset (get-text-property pos 'charset))
+          (coding (or (terminal-coding-system) 'us-ascii))
+          (encoded (encode-coding-char char coding charset)))
       (if encoded
          (encoded-string-description encoded coding)))))
 
 \f
+;; Return a string of CH with composition for padding on both sides.
+;; It is displayed without overlapping with the left/right columns.
+(defsubst describe-char-padded-string (ch)
+  (compose-string (string ch) 0 1 (format "\t%c\t" ch)))
+
+;; Return a nicely formated list of categories; extended category
+;; description is added to the category name as a tooltip
+(defsubst describe-char-categories (category-set)
+  (let ((mnemonics (category-set-mnemonics category-set)))
+    (unless (eq mnemonics "")
+      (list (mapconcat
+            #'(lambda (x)
+                (let* ((c (category-docstring x))
+                       (doc (if (string-match "\\`\\(.*?\\)\n\\(.*\\)\\'" c)
+                                (propertize (match-string 1 c)
+                                            'help-echo (match-string 2 c))
+                              c)))
+                  (format "%c:%s" x doc)))
+            mnemonics ", ")))))
+
 ;;;###autoload
 (defun describe-char (pos)
   "Describe the character after POS (interactively, the character after point).
@@ -415,7 +380,9 @@ as well as widgets, buttons, overlays, and text properties."
   (if (>= pos (point-max))
       (error "No character follows specified position"))
   (let* ((char (char-after pos))
-        (charset (char-charset char))
+        (eight-bit-p (and (not enable-multibyte-characters) (>= char 128)))
+        (charset (if eight-bit-p 'eight-bit
+                   (or (get-text-property pos 'charset) (char-charset char))))
         (composition (find-composition pos nil nil t))
         (component-chars nil)
         (display-table (or (window-display-table)
@@ -438,127 +405,180 @@ as well as widgets, buttons, overlays, and text properties."
                  (describe-text-properties pos tmp-buf)
                  (with-current-buffer tmp-buf (buffer-string)))
              (kill-buffer tmp-buf))))
-        item-list max-width unicode)
+        item-list max-width code)
+
+    (if multibyte-p
+       (or (setq code (encode-char char charset))
+           (setq charset (char-charset char)
+                 code (encode-char char charset)))
+      (setq code char))
+    (when composition
+      ;; When the composition is trivial (i.e. composed only with the
+      ;; current character itself without any alternate characters),
+      ;; we don't show the composition information.  Otherwise, store
+      ;; two descriptive strings in the first two elments of
+      ;; COMPOSITION.
+      (or (catch 'tag
+           (let ((from (car composition))
+                 (to (nth 1 composition))
+                 (next (1+ pos))
+                 (components (nth 2 composition))
+                 ch)
+             (if (and (vectorp components) (vectorp (aref components 0)))
+                 (let ((idx (- pos from))
+                       (nglyphs (lgstring-glyph-len components))
+                       (i 0) j glyph glyph-from)
+                   ;; COMPONENTS is a gstring.  Find a grapheme
+                   ;; cluster containing the current character.
+                   (while (and (< i nglyphs)
+                               (setq glyph (lgstring-glyph components i))
+                               (< (lglyph-to glyph) idx))
+                     (setq i (1+ i)))
+                   (if (or (not glyph) (= i nglyphs))
+                       ;; The composition is broken.
+                       (throw 'tag nil))
+                   (setq glyph-from (lglyph-from glyph)
+                         to (+ from (lglyph-to glyph) 1)
+                         from (+ from glyph-from)
+                         j i)
+                   (while (and (< j nglyphs)
+                               (setq glyph (lgstring-glyph components j))
+                               (= (lglyph-from glyph) glyph-from))
+                     (setq j (1+ j)))
+                   (if (and (= i (1- j))
+                            (setq glyph (lgstring-glyph components i))
+                            (= char (lglyph-char glyph)))
+                       ;; The composition is trivial.
+                       (throw 'tag nil))
+                   (nconc composition (list i (1- j))))
+               (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)))
+             (if (< from pos)
+                 (if (< (1+ pos) to)
+                     (setcar composition
+                             (concat
+                              " with the surrounding characters \""
+                              (mapconcat 'describe-char-padded-string
+                                         (buffer-substring from pos) "")
+                              "\" and \""
+                              (mapconcat 'describe-char-padded-string
+                                         (buffer-substring (1+ pos) to) "")
+                              "\""))
+                   (setcar composition
+                           (concat
+                            " with the preceding character(s) \""
+                            (mapconcat 'describe-char-padded-string
+                                       (buffer-substring from pos) "")
+                            "\"")))
+               (if (< (1+ pos) to)
+                   (setcar composition
+                           (concat
+                            " with the following character(s) \""
+                            (mapconcat 'describe-char-padded-string
+                                       (buffer-substring (1+ pos) to) "")
+                            "\""))
+                 (setcar composition nil)))
+             (setcar (cdr composition)
+                     (format "composed to form \"%s\" (see below)"
+                             (buffer-substring from to)))))
+         (setq composition nil)))
 
-    (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 (%d, #o%o, #x%x%s)"
+            ,(format "%s (%d, #o%o, #x%x)"
                      (apply 'propertize char-description
                             (text-properties-at pos))
-                     char char char
-                     (if unicode
-                         (format ", U+%04X" unicode)
-                       "")))
-           ("charset"
+                     char char char))
+           ("preferred charset"
             ,`(insert-text-button
                ,(symbol-name charset)
                'type 'help-character-set 'help-args '(,charset))
             ,(format "(%s)" (charset-description charset)))
            ("code point"
-            ,(let ((split (split-char char)))
-               `(insert-text-button
-                 ,(if (= (charset-dimension charset) 1)
-                      (format "#x%02X" (nth 1 split))
-                    (format "#x%02X #x%02X" (nth 1 split)
-                            (nth 2 split)))
-                 'action (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))))
-                 'help-echo
-                 "mouse-2, RET: show this character in its character set")))
+            ,(let ((str (if (integerp code)
+                            (format (if (< code 256) "0x%02X" "0x%04X") code)
+                          (format "0x%04X%04X" (car code) (cdr code)))))
+               (if (<= (charset-dimension charset) 2)
+                   `(insert-text-button
+                     ,str
+                     'action (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))
+                                   (if (search-forward ,(char-to-string char)
+                                                       nil t)
+                                       (goto-char (match-beginning 0))))))
+                     'follow-link t
+                     'help-echo
+                     "mouse-2, RET: show this character in its character set")
+                 str)))
            ("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)))))
+            ,@(if (not eight-bit-p)
+                  (let ((category-set (char-category-set char)))
+                    (if category-set
+                        (describe-char-categories category-set)
+                      '("-- none --")))))
            ("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"
-                          `(insert-text-button
-                            ,current-input-method
-                            'type 'help-input-method
-                            'help-args '(,current-input-method))))))
+            ,@(if (not eight-bit-p)
+                  (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"
+                              `(insert-text-button
+                                ,current-input-method
+                                'type 'help-input-method
+                                'help-args '(,current-input-method)))))))
            ("buffer code"
-            ,(encoded-string-description
-              (string-as-unibyte (char-to-string char)) nil))
+            ,(if multibyte-p
+                 (encoded-string-description
+                  (string-as-unibyte (char-to-string char)) nil)
+               (format "#x%02X" char)))
            ("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 multibyte-p
+                  (let* ((coding buffer-file-coding-system)
+                         (encoded (encode-coding-char char coding charset)))
+                    (if encoded
+                        (list (encoded-string-description encoded coding)
+                              (format "(encoded by coding system %S)" coding))
+                      (list "not encodable by coding system"
+                            (symbol-name coding))))
+                (list (format "#x%02X" char))))
            ("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 (glyph-char char)))))
+                       (cons (aref disp-vector i)
+                             (describe-char-display
+                              pos (glyph-char (aref disp-vector i))))))
                (format "by display table entry [%s] (see below)"
                        (mapconcat
                         #'(lambda (x)
                             (format "?%c" (glyph-char (car x))))
                         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))))
+               (cadr composition))
               (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 (#x%02X)"
-                                  (car display) (cdr display)))
+                         (concat "by this font (glyph code)\n    " display)
                        "no font available")
                    (if display
                        (format "terminal code %s" display)
@@ -568,11 +588,11 @@ as well as widgets, buttons, overlays, and text properties."
                         (cond
                          ((and show-trailing-whitespace
                                (save-excursion (goto-char pos)
-                                               (looking-at "[ \t]+$")))
+                                               (looking-at-p "[ \t]+$")))
                           'trailing-whitespace)
-                         ((and nobreak-char-display unicode (eq unicode '#xa0))
+                         ((and nobreak-char-display char (eq char '#xa0))
                           'nobreak-space)
-                         ((and nobreak-char-display unicode (eq unicode '#xad))
+                         ((and nobreak-char-display char (eq char '#xad))
                           'escape-glyph)
                          ((and (< char 32) (not (memq char '(9 10))))
                           'escape-glyph)))))
@@ -580,10 +600,10 @@ as well as widgets, buttons, overlays, and text properties."
                                     `(insert-text-button
                                       ,(symbol-name face)
                                       'type 'help-face 'help-args '(,face))))))
-           ,@(let ((unicodedata (and unicode
-                                     (describe-char-unicode-data unicode))))
-               (if unicodedata
-                   (cons (list "Unicode data" " ") unicodedata)))))
+           ,@(if (not eight-bit-p)
+                 (let ((unicodedata (describe-char-unicode-data char)))
+                   (if unicodedata
+                       (cons (list "Unicode data" " ") unicodedata))))))
     (setq max-width (apply #'max (mapcar #'(lambda (x)
                                             (if (cadr x) (length (car x)) 0))
                                         item-list)))
@@ -599,7 +619,7 @@ as well as widgets, buttons, overlays, and text properties."
                (if (eq (car-safe clm) 'insert-text-button)
                    (progn (insert " ") (eval clm))
                  (when (>= (+ (current-column)
-                              (or (string-match "\n" clm)
+                              (or (string-match-p "\n" clm)
                                   (string-width clm))
                               1)
                            (window-width))
@@ -612,7 +632,7 @@ as well as widgets, buttons, overlays, and text properties."
          (save-excursion
            (goto-char (point-min))
            (re-search-forward "character:[ \t\n]+")
-           (let* ((end (+ (point) (length char-description))))
+           (let ((end (+ (point) (length char-description))))
              (mapc #'(lambda (props)
                        (let ((o (make-overlay (point) end)))
                          (while props
@@ -629,10 +649,7 @@ as well as widgets, buttons, overlays, and text properties."
                (dotimes (i (length disp-vector))
                  (insert (glyph-char (car (aref disp-vector i))) ?:
                          (propertize " " 'display '(space :align-to 5))
-                         (if (cdr (aref disp-vector i))
-                             (format "%s (#x%02X)" (cadr (aref disp-vector i))
-                                     (cddr (aref disp-vector i)))
-                           "-- no font --")
+                         (or (cdr (aref disp-vector i)) "-- no font --")
                          "\n")
                  (let ((face (glyph-face (car (aref disp-vector i)))))
                    (when face
@@ -650,45 +667,87 @@ as well as widgets, buttons, overlays, and text properties."
        (when composition
          (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 (#x%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"))
+             (insert (car composition)))
+         (if (and (vectorp (nth 2 composition))
+                  (vectorp (aref (nth 2 composition) 0)))
+             (let* ((gstring (nth 2 composition))
+                    (font (lgstring-font gstring))
+                    (from (nth 3 composition))
+                    (to (nth 4 composition))
+                    glyph)
+               (if (fontp font)
+                   (progn
+                     (insert " using this font:\n  "
+                             (symbol-name (font-get font :type))
+                             ?:
+                             (aref (query-font font) 0)
+                             "\nby these glyphs:\n")
+                     (while (and (<= from to)
+                                 (setq glyph (lgstring-glyph gstring from)))
+                       (insert (format "  %S\n" glyph))
+                       (setq from (1+ from))))
+                 (insert " by these characters:\n")
+                 (while (and (<= from to)
+                             (setq glyph (lgstring-glyph gstring from)))
+                   (insert (format " %c (#x%d)\n"
+                                   (lglyph-char glyph) (lglyph-char glyph)))
+                   (setq from (1+ from)))))
+           (insert " by the rule:\n\t(")
+           (let ((first t))
+             (mapc (lambda (x)
+                     (if first (setq first nil)
+                       (insert " "))
+                     (if (consp x) (insert (format "%S" x))
+                       (if (= x ?\t) (insert (single-key-description x))
+                         (insert ??)
+                         (insert (describe-char-padded-string 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)
+                   (if (/= (car elt) ?\t)
+                       (insert "\n "
+                               (describe-char-padded-string (car elt))
+                               ?:
+                               (propertize " " 'display '(space :align-to 5))
+                               (or (cdr elt) "-- no font --")))))
+             (insert "these terminal codes:")
+             (dolist (elt component-chars)
+               (insert "\n  " (car elt) ":"
+                       (propertize " " 'display '(space :align-to 4))
+                       (or (cdr elt) "-- not encodable --"))))
+           (insert "\nSee the variable `reference-point-alist' for "
+                   "the meaning of the rule.\n")))
+
+       (unless eight-bit-p
+         (insert (if (not describe-char-unidata-list)
+                     "\nCharacter code properties are not shown: "
+                   "\nCharacter code properties: "))
+         (insert-text-button
+          "customize what to show"
+          'action (lambda (&rest ignore)
+                    (customize-variable
+                     'describe-char-unidata-list))
+          'follow-link t)
+         (insert "\n")
+         (dolist (elt (if (eq describe-char-unidata-list t)
+                          (nreverse (mapcar 'car char-code-property-alist))
+                        describe-char-unidata-list))
+           (let ((val (get-char-code-property char elt))
+                 description)
+             (when val
+               (setq description (char-code-property-description elt val))
+               (insert (if description
+                           (format "  %s: %s (%s)\n" elt val description)
+                         (format "  %s: %s\n" elt val)))))))
 
         (if text-props-desc (insert text-props-desc))
        (setq help-xref-stack-item (list 'help-insert-string (buffer-string)))
        (toggle-read-only 1)))))
 
-(defalias 'describe-char-after 'describe-char)
-(make-obsolete 'describe-char-after 'describe-char "22.1")
+(define-obsolete-function-alias 'describe-char-after 'describe-char "22.1")
 
 (provide 'descr-text)