(menu-bar-options-menu): Delete "Syntax

[bpt/emacs.git] / lisp / help-mode.el

diff --git a/lisp/help-mode.el b/lisp/help-mode.el
index 1f1b529..a2e7fb8 100644 (file)
--- a/lisp/help-mode.el
+++ b/lisp/help-mode.el
@@ -1,7 +1,7 @@
 ;;; help-mode.el --- `help-mode' used by *Help* buffers
 
-;; Copyright (C) 1985, 1986, 1993, 1994, 1998, 1999, 2000, 2001, 2002, 2004
-;;   Free Software Foundation, Inc.
+;; Copyright (C) 1985, 1986, 1993, 1994, 1998, 1999, 2000, 2001, 2002,
+;;   2003, 2004, 2005 Free Software Foundation, Inc.
 
 ;; Maintainer: FSF
 ;; Keywords: help, internal
@@ -20,8 +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:
 
@@ -68,6 +68,7 @@ The format is (FUNCTION ARGS...).")
 ;; Button types used by help
 
 (define-button-type 'help-xref
+  'follow-link t
   'action #'help-button-action)
 
 (defun help-button-action (button)
@@ -125,7 +126,12 @@ The format is (FUNCTION ARGS...).")
 (define-button-type 'help-info
   :supertype 'help-xref
   'help-function #'info
-  'help-echo (purecopy"mouse-2, RET: read this Info node"))
+  'help-echo (purecopy "mouse-2, RET: read this Info node"))
+
+(define-button-type 'help-url
+  :supertype 'help-xref
+  'help-function #'browse-url
+  'help-echo (purecopy "mouse-2, RET: view this URL in a browser"))
 
 (define-button-type 'help-customize-variable
   :supertype 'help-xref
@@ -168,6 +174,18 @@ The format is (FUNCTION ARGS...).")
                     (goto-char (cdr location))))
   'help-echo (purecopy"mouse-2, RET: find variable's definition"))
 
+(define-button-type 'help-face-def
+  :supertype 'help-xref
+  'help-function (lambda (fun file)
+                  (require 'find-func)
+                  ;; Don't use find-function-noselect because it follows
+                  ;; aliases (which fails for built-in functions).
+                  (let ((location
+                         (find-function-search-for-symbol fun 'defface file)))
+                    (pop-to-buffer (car location))
+                    (goto-char (cdr location))))
+  'help-echo (purecopy "mouse-2, RET: find face's definition"))
+
 \f
 ;;;###autoload
 (defun help-mode ()
@@ -183,7 +201,7 @@ Commands:
   (view-mode)
   (make-local-variable 'view-no-disable-on-exit)
   (setq view-no-disable-on-exit t)
-  (run-hooks 'help-mode-hook))
+  (run-mode-hooks 'help-mode-hook))
 
 ;;;###autoload
 (defun help-mode-setup ()
@@ -193,8 +211,12 @@ Commands:
 ;;;###autoload
 (defun help-mode-finish ()
   (let ((entry (assq (selected-window) view-return-to-alist)))
-       (if entry (setcdr entry (cons (selected-window)
-                                     help-return-method))
+       (if entry
+           ;; When entering Help mode from the Help window,
+           ;; such as by following a link, preserve the same
+           ;; meaning for the q command.
+           ;; (setcdr entry (cons (selected-window) help-return-method))
+           nil
          (setq view-return-to-alist
                (cons (cons (selected-window) help-return-method)
                      view-return-to-alist))))
@@ -240,6 +262,10 @@ when help commands related to multilingual environment (e.g.,
   (purecopy "\\<[Ii]nfo[ \t\n]+\\(node\\|anchor\\)[ \t\n]+`\\([^']+\\)'")
   "Regexp matching doc string references to an Info node.")
 
+(defconst help-xref-url-regexp
+  (purecopy "\\<[Uu][Rr][Ll][ \t\n]+`\\([^']+\\)'")
+  "Regexp matching doc string references to a URL.")
+
 ;;;###autoload
 (defun help-setup-xref (item interactive-p)
   "Invoked from commands using the \"*Help*\" buffer to install some xref info.
@@ -321,6 +347,11 @@ that."
                      (unless (string-match "^([^)]+)" data)
                        (setq data (concat "(emacs)" data))))
                    (help-xref-button 2 'help-info data))))
+              ;; URLs
+              (save-excursion
+                (while (re-search-forward help-xref-url-regexp nil t)
+                  (let ((data (match-string 1)))
+                   (help-xref-button 1 'help-url data))))
              ;; Mule related keywords.  Do this before trying
              ;; `help-xref-symbol-regexp' because some of Mule
              ;; keywords have variable or function definitions.
@@ -371,9 +402,10 @@ that."
 ;;;                            (pop-to-buffer (car location))
 ;;;                            (goto-char (cdr location))))
                          (help-xref-button 8 'help-function-def sym))
-                        ((facep sym)
-                         (if (save-match-data (looking-at "[ \t\n]+face\\W"))
-                             (help-xref-button 8 'help-face sym)))
+                        ((and
+                           (facep sym)
+                           (save-match-data (looking-at "[ \t\n]+face\\W")))
+                          (help-xref-button 8 'help-face sym))
                          ((and (boundp sym) (fboundp sym))
                           ;; We can't intuit whether to use the
                           ;; variable or function doc -- supply both.
@@ -577,12 +609,11 @@ help buffer."
        (goto-char position)))))
 
 (defun help-go-back ()
-  "Invoke the [back] button (if any) in the Help mode buffer."
+  "Go back to previous topic in this help buffer."
   (interactive)
-  (let ((back-button (button-at (1- (point-max)))))
-    (if back-button
-       (button-activate back-button)
-      (error "No [back] button"))))
+  (if help-xref-stack
+      (help-xref-go-back (current-buffer))
+    (error "No previous help buffer")))
 
 (defun help-do-xref (pos function args)
   "Call the help cross-reference function FUNCTION with args ARGS.
@@ -614,5 +645,5 @@ For the cross-reference format, see `help-make-xrefs'."
 
 (provide 'help-mode)
 
-;;; arch-tag: 850954ae-3725-4cb4-8e91-0bf6d52d6b0b
+;; arch-tag: 850954ae-3725-4cb4-8e91-0bf6d52d6b0b
 ;;; help-mode.el ends here