diff options
Diffstat (limited to 'lisp')
| -rw-r--r-- | lisp/help.el | 51 |
1 files changed, 31 insertions, 20 deletions
diff --git a/lisp/help.el b/lisp/help.el index 1c15f4f87e4..8d9f94f4254 100644 --- a/lisp/help.el +++ b/lisp/help.el @@ -122,11 +122,14 @@ (defvar help-xref-stack nil "A stack of ways by which to return to help buffers after following xrefs. -Used by `help-follow' and `help-xref-go-back'.") +Used by `help-follow' and `help-xref-go-back'. +An element looks like (POSITION FUNCTION ARGS...). +To use the element, do (apply FUNCTION ARGS) then (goto-char POSITION).") (put 'help-xref-stack 'permanent-local t) (defvar help-xref-stack-item nil - "An item for `help-follow' in this buffer to push onto `help-xref-stack'.") + "An item for `help-follow' in this buffer to push onto `help-xref-stack'. +The format is (FUNCTION ARGS...).") (put 'help-xref-stack-item 'permanent-local t) (setq-default help-xref-stack nil help-xref-stack-item nil) @@ -377,7 +380,7 @@ followed by the major mode, which is described on the last page.\n\f\n")) (princ mode-name) (princ " mode:\n") (princ (documentation major-mode)) - (help-setup-xref (cons #'help-xref-mode (current-buffer)) (interactive-p)) + (help-setup-xref (list #'help-xref-mode (current-buffer)) (interactive-p)) (print-help-return-message))) ;; So keyboard macro definitions are documented correctly @@ -658,7 +661,7 @@ C-w Display information on absence of warranty for GNU Emacs." (if doc (progn (terpri) (princ doc) - (help-setup-xref (cons #'describe-function function) (interactive-p))) + (help-setup-xref (list #'describe-function function) (interactive-p))) (princ "not documented"))))) ;; We return 0 if we can't find a variable to return. @@ -732,7 +735,7 @@ Returns the documentation as a string, also." (terpri) (let ((doc (documentation-property variable 'variable-documentation))) (princ (or doc "not documented as a variable."))) - (help-setup-xref (cons #'describe-variable variable) (interactive-p)) + (help-setup-xref (list #'describe-variable variable) (interactive-p)) ;; Make a link to customize if this variable can be customized. (if (or (get variable 'custom-type) @@ -756,17 +759,21 @@ Returns the documentation as a string, also." (buffer-string)))) (message "You did not specify a variable"))) -(defun describe-bindings (&optional prefix) +(defun describe-bindings (&optional prefix buffer) "Show a list of all defined keys, and their definitions. We put that list in a buffer, and display the buffer. The optional argument PREFIX, if non-nil, should be a key sequence; -then we display only bindings that start with that prefix." +then we display only bindings that start with that prefix. +The optional argument BUFFER specifies which buffer's bindings +to display (default, the current buffer)." (interactive "P") - (describe-bindings-internal nil prefix) + (or buffer (setq buffer (current-buffer))) + (with-current-buffer buffer + (describe-bindings-internal nil prefix)) (with-current-buffer "*Help*" - (setq help-xref-stack nil - help-xref-stack-item nil))) + (help-setup-xref (list #'describe-bindings prefix buffer) + (interactive-p)))) (defun where-is (definition &optional insert) "Print message listing key sequences that invoke specified command. @@ -889,7 +896,7 @@ distinguish references to variables, functions and symbols.") (defun help-setup-xref (item interactive-p) "Invoked from commands using the \"*Help*\" buffer to install some xref info. -ITEM is a (function . args) pair appropriate for recreating the help +ITEM is a (FUNCTION . ARGS) pair appropriate for recreating the help buffer after following a reference. INTERACTIVE-P is non-nil if the calling command was invoked interactively. In this case the stack of items for help buffer \"back\" buttons is cleared." @@ -1032,7 +1039,7 @@ help buffer." (goto-char (point-max)) (insert "\n\n" fdoc)) (goto-char (point-min)) - (help-setup-xref (cons #'help-xref-interned symbol) nil)) + (help-setup-xref (list #'help-xref-interned symbol) nil)) (defun help-xref-mode (buffer) "Do a `describe-mode' for the specified BUFFER." @@ -1055,17 +1062,17 @@ help buffer." (defun help-xref-go-back (buffer) "Go back to the previous help buffer text using info on `help-xref-stack'." (interactive) - (let (item method args) + (let (item position method args) (with-current-buffer buffer (when help-xref-stack (setq help-xref-stack (cdr help-xref-stack)) ; due to help-follow (setq item (car help-xref-stack) - method (car item) - args (cdr item)) + position (car item) + method (cadr item) + args (cddr item)) (setq help-xref-stack (cdr help-xref-stack)))) - (if (listp args) - (apply method args) - (funcall method args)))) + (apply method args) + (goto-char position))) (defun help-go-back () (interactive) @@ -1076,10 +1083,14 @@ help buffer." For the cross-reference format, see `help-make-xrefs'." (interactive "d") - (let* ((help-data (get-text-property pos 'help-xref)) + (let* ((help-data (or (and (not (= pos (point-max))) + (get-text-property pos 'help-xref)) + (and (not (= pos (point-min))) + (get-text-property (1- pos) 'help-xref)))) (method (car help-data)) (args (cdr help-data))) - (setq help-xref-stack (cons help-xref-stack-item help-xref-stack)) + (setq help-xref-stack (cons (cons (point) help-xref-stack-item) + help-xref-stack)) (setq help-xref-stack-item nil) (when help-data ;; There is a reference at point. Follow it. |