+(defun notmuch-documentation-first-line (symbol)
+ "Return the first line of the documentation string for SYMBOL."
+ (let ((doc (documentation symbol)))
+ (if doc
+ (with-temp-buffer
+ (insert (documentation symbol t))
+ (goto-char (point-min))
+ (let ((beg (point)))
+ (end-of-line)
+ (buffer-substring beg (point))))
+ "")))
+
+(defun notmuch-prefix-key-description (key)
+ "Given a prefix key code, return a human-readable string representation.
+
+This is basically just `format-kbd-macro' but we also convert ESC to M-."
+ (let* ((key-vector (if (vectorp key) key (vector key)))
+ (desc (format-kbd-macro key-vector)))
+ (if (string= desc "ESC")
+ "M-"
+ (concat desc " "))))
+
+
+(defun notmuch-describe-key (actual-key binding prefix ua-keys tail)
+ "Prepend cons cells describing prefix-arg ACTUAL-KEY and ACTUAL-KEY to TAIL
+
+It does not prepend if ACTUAL-KEY is already listed in TAIL."
+ (let ((key-string (concat prefix (format-kbd-macro actual-key))))
+ ;; We don't include documentation if the key-binding is
+ ;; over-ridden. Note, over-riding a binding automatically hides the
+ ;; prefixed version too.
+ (unless (assoc key-string tail)
+ (when (and ua-keys (symbolp binding)
+ (get binding 'notmuch-prefix-doc))
+ ;; Documentation for prefixed command
+ (let ((ua-desc (key-description ua-keys)))
+ (push (cons (concat ua-desc " " prefix (format-kbd-macro actual-key))
+ (get binding 'notmuch-prefix-doc))
+ tail)))
+ ;; Documentation for command
+ (push (cons key-string
+ (or (and (symbolp binding) (get binding 'notmuch-doc))
+ (notmuch-documentation-first-line binding)))
+ tail)))
+ tail)
+
+(defun notmuch-describe-remaps (remap-keymap ua-keys base-keymap prefix tail)
+ ;; Remappings are represented as a binding whose first "event" is
+ ;; 'remap. Hence, if the keymap has any remappings, it will have a
+ ;; binding whose "key" is 'remap, and whose "binding" is itself a
+ ;; keymap that maps not from keys to commands, but from old (remapped)
+ ;; functions to the commands to use in their stead.
+ (map-keymap
+ (lambda (command binding)
+ (mapc
+ (lambda (actual-key)
+ (setq tail (notmuch-describe-key actual-key binding prefix ua-keys tail)))
+ (where-is-internal command base-keymap)))
+ remap-keymap)
+ tail)
+
+(defun notmuch-describe-keymap (keymap ua-keys base-keymap &optional prefix tail)
+ "Return a list of cons cells, each describing one binding in KEYMAP.
+
+Each cons cell consists of a string giving a human-readable
+description of the key, and a one-line description of the bound
+function. See `notmuch-help' for an overview of how this
+documentation is extracted.
+
+UA-KEYS should be a key sequence bound to `universal-argument'.
+It will be used to describe bindings of commands that support a
+prefix argument. PREFIX and TAIL are used internally."
+ (map-keymap
+ (lambda (key binding)
+ (cond ((mouse-event-p key) nil)
+ ((keymapp binding)
+ (setq tail
+ (if (eq key 'remap)
+ (notmuch-describe-remaps
+ binding ua-keys base-keymap prefix tail)
+ (notmuch-describe-keymap
+ binding ua-keys base-keymap (notmuch-prefix-key-description key) tail))))
+ (binding
+ (setq tail (notmuch-describe-key (vector key) binding prefix ua-keys tail)))))
+ keymap)
+ tail)
+
+(defun notmuch-substitute-command-keys (doc)
+ "Like `substitute-command-keys' but with documentation, not function names."
+ (let ((beg 0))
+ (while (string-match "\\\\{\\([^}[:space:]]*\\)}" doc beg)
+ (let ((desc
+ (save-match-data
+ (let* ((keymap-name (substring doc (match-beginning 1) (match-end 1)))
+ (keymap (symbol-value (intern keymap-name)))
+ (ua-keys (where-is-internal 'universal-argument keymap t))
+ (desc-alist (notmuch-describe-keymap keymap ua-keys keymap))
+ (desc-list (mapcar (lambda (arg) (concat (car arg) "\t" (cdr arg))) desc-alist)))
+ (mapconcat #'identity desc-list "\n")))))
+ (setq doc (replace-match desc 1 1 doc)))
+ (setq beg (match-end 0)))
+ doc))
+
+(defun notmuch-help ()
+ "Display help for the current notmuch mode.
+
+This is similar to `describe-function' for the current major
+mode, but bindings tables are shown with documentation strings
+rather than command names. By default, this uses the first line
+of each command's documentation string. A command can override
+this by setting the 'notmuch-doc property of its command symbol.
+A command that supports a prefix argument can explicitly document
+its prefixed behavior by setting the 'notmuch-prefix-doc property
+of its command symbol."
+ (interactive)
+ (let* ((mode major-mode)
+ (doc (substitute-command-keys (notmuch-substitute-command-keys (documentation mode t)))))
+ (with-current-buffer (generate-new-buffer "*notmuch-help*")
+ (insert doc)
+ (goto-char (point-min))
+ (set-buffer-modified-p nil)
+ (view-buffer (current-buffer) 'kill-buffer-if-not-modified))))
+
+(defun notmuch-subkeymap-help ()
+ "Show help for a subkeymap."
+ (interactive)
+ (let* ((key (this-command-keys-vector))
+ (prefix (make-vector (1- (length key)) nil))
+ (i 0))
+ (while (< i (length prefix))
+ (aset prefix i (aref key i))
+ (setq i (1+ i)))
+
+ (let* ((subkeymap (key-binding prefix))
+ (ua-keys (where-is-internal 'universal-argument nil t))
+ (prefix-string (notmuch-prefix-key-description prefix))
+ (desc-alist (notmuch-describe-keymap subkeymap ua-keys subkeymap prefix-string))
+ (desc-list (mapcar (lambda (arg) (concat (car arg) "\t" (cdr arg))) desc-alist))
+ (desc (mapconcat #'identity desc-list "\n")))
+ (with-help-window (help-buffer)
+ (with-current-buffer standard-output
+ (insert "\nPress 'q' to quit this window.\n\n")
+ (insert desc)))
+ (pop-to-buffer (help-buffer)))))
+
projects / notmuch / blobdiff