(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
'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"))
(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.
(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.
(if sym
(cond
((match-string 3) ; `variable' &c
- (and (boundp sym) ; `variable' doesn't ensure
+ (and (or (boundp sym) ; `variable' doesn't ensure
; it's actually bound
+ (get sym 'variable-documentation))
(help-xref-button 8 'help-variable sym)))
((match-string 4) ; `function' &c
(and (fboundp sym) ; similarly
(facep sym)
(save-match-data (looking-at "[ \t\n]+face\\W")))
(help-xref-button 8 'help-face sym))
- ((and (boundp sym) (fboundp sym))
+ ((and (or (boundp sym)
+ (get sym 'variable-documentation))
+ (fboundp sym))
;; We can't intuit whether to use the
;; variable or function doc -- supply both.
(help-xref-button 8 'help-symbol sym))
((and
- (boundp sym)
+ (or (boundp sym)
+ (get sym 'variable-documentation))
(or
(documentation-property
sym 'variable-documentation)
((or (memq sym '(t nil))
(keywordp sym))
nil)
- ((and sym (boundp sym))
+ ((and sym
+ (or (boundp sym)
+ (get sym
+ 'variable-documentation)))
'help-variable))))
(when type (help-xref-button 1 type sym)))
(goto-char (match-end 1)))
;; Don't record the current entry in the stack.
(setq help-xref-stack-item nil)
(describe-function symbol)))
- (sdoc (when (boundp symbol)
+ (sdoc (when (or (boundp symbol)
+ (get symbol 'variable-documentation))
;; Don't record the current entry in the stack.
(setq help-xref-stack-item nil)
(describe-variable symbol))))
(buffer-substring (point)
(progn (skip-syntax-forward "w_")
(point)))))))
- (when (or (boundp sym) (fboundp sym) (facep sym))
+ (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)