(Abbrevs): A @node line without explicit Prev, Next, and Up links.

[gnu-emacs] / lisp / help-mode.el

diff --git a/lisp/help-mode.el b/lisp/help-mode.el
index b7cea179aead826edec6d0f9e9a097a61f45034c..0c6e0f47453b94f2eae83650bc52d835eb710e49 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,
-;;   2003, 2004, 2005 Free Software Foundation, Inc.
+;;   2003, 2004, 2005, 2006 Free Software Foundation, Inc.
 
 ;; Maintainer: FSF
 ;; Keywords: help, internal
@@ -40,7 +40,7 @@
 
 (define-key help-mode-map [mouse-2] 'help-follow-mouse)
 (define-key help-mode-map "\C-c\C-b" 'help-go-back)
-(define-key help-mode-map "\C-c\C-c" 'help-follow)
+(define-key help-mode-map "\C-c\C-c" 'help-follow-symbol)
 ;; Documentation only, since we use minor-mode-overriding-map-alist.
 (define-key help-mode-map "\r" 'help-follow)
 
@@ -136,16 +136,12 @@ The format is (FUNCTION ARGS...).")
 (define-button-type 'help-customize-variable
   :supertype 'help-xref
   'help-function (lambda (v)
-                  (if help-xref-stack
-                      (pop help-xref-stack))
                   (customize-variable v))
   'help-echo (purecopy "mouse-2, RET: customize variable"))
 
 (define-button-type 'help-customize-face
   :supertype 'help-xref
   'help-function (lambda (v)
-                  (if help-xref-stack
-                      (pop help-xref-stack))
                   (customize-face v))
   'help-echo (purecopy "mouse-2, RET: customize face"))
 
@@ -201,6 +197,10 @@ Commands:
   (view-mode)
   (make-local-variable 'view-no-disable-on-exit)
   (setq view-no-disable-on-exit t)
+  (setq view-exit-action (lambda (buffer)
+                          (or (window-minibuffer-p (selected-window))
+                              (one-window-p t)
+                              (delete-window))))
   (run-mode-hooks 'help-mode-hook))
 
 ;;;###autoload
@@ -237,10 +237,10 @@ Commands:
   "Label to use by `help-make-xrefs' for the go-back reference.")
 
 (defconst help-xref-symbol-regexp
-  (purecopy (concat "\\(\\<\\(\\(variable\\|option\\)\\|"
-                   "\\(function\\|command\\)\\|"
-                   "\\(face\\)\\|"
-                   "\\(symbol\\)\\|"
+  (purecopy (concat "\\(\\<\\(\\(variable\\|option\\)\\|"  ; Link to var
+                   "\\(function\\|command\\)\\|"          ; Link to function
+                   "\\(face\\)\\|"                        ; Link to face
+                   "\\(symbol\\|program\\)\\|"            ; Don't link
                    "\\(source \\(?:code \\)?\\(?:of\\|for\\)\\)\\)"
                    "[ \t\n]+\\)?"
                    ;; Note starting with word-syntax character:
@@ -588,15 +588,6 @@ help buffer."
 \f
 ;; Navigation/hyperlinking with xrefs
 
-(defun help-follow-mouse (click)
-  "Follow the cross-reference that you CLICK on."
-  (interactive "e")
-  (let* ((start (event-start click))
-        (window (car start))
-        (pos (car (cdr start))))
-    (with-current-buffer (window-buffer window)
-      (help-follow pos))))
-
 (defun help-xref-go-back (buffer)
   "From BUFFER, go back to previous help buffer text using `help-xref-stack'."
   (let (item position method args)
@@ -631,27 +622,48 @@ a proper [back] button."
   (let ((help-xref-following t))
     (apply function args)))
 
-(defun help-follow (&optional pos)
-  "Follow cross-reference at POS, defaulting to point.
+;; The doc string is meant to explain what buttons do.
+(defun help-follow-mouse ()
+  "Follow the cross-reference that you click on."
+  (interactive)
+  (error "No cross-reference here"))
+
+;; The doc string is meant to explain what buttons do.
+(defun help-follow ()
+  "Follow cross-reference at point.
 
 For the cross-reference format, see `help-make-xrefs'."
+  (interactive)
+  (error "No cross-reference here"))
+
+(defun help-follow-symbol (&optional pos)
+  "In help buffer, show docs for symbol at POS, defaulting to point.
+Show all docs for that symbol as either a variable, function or face."
   (interactive "d")
   (unless pos
     (setq pos (point)))
-  (unless (push-button pos)
-    ;; check if the symbol under point is a function or variable
-    (let ((sym
-          (intern
-           (save-excursion
-             (goto-char pos) (skip-syntax-backward "w_")
-             (buffer-substring (point)
-                               (progn (skip-syntax-forward "w_")
-                                      (point)))))))
-      (when (or (boundp sym)
-               (get sym 'variable-documentation)
-               (fboundp sym) (facep sym))
-       (help-do-xref pos #'help-xref-interned (list sym))))))
-
+  ;; check if the symbol under point is a function, variable or face
+  (let ((sym
+        (intern
+         (save-excursion
+           (goto-char pos) (skip-syntax-backward "w_")
+           (buffer-substring (point)
+                             (progn (skip-syntax-forward "w_")
+                                    (point)))))))
+    (when (or (boundp sym)
+             (get sym 'variable-documentation)
+             (fboundp sym) (facep sym))
+      (help-do-xref pos #'help-xref-interned (list sym)))))
+
+(defun help-insert-string (string)
+  "Insert STRING to the help buffer and install xref info for it.
+This function can be used to restore the old contents of the help buffer
+when going back to the previous topic in the xref stack.  It is needed
+in case when it is impossible to recompute the old contents of the
+help buffer by other means."
+  (setq help-xref-stack-item (list #'help-insert-string string))
+  (with-output-to-temp-buffer (help-buffer)
+    (insert string)))
 
 (provide 'help-mode)