;;; help-macro.el --- makes command line help such as help-for-help ;; Copyright (C) 1993, 1994, 2001, 2002, 2003, 2004, ;; 2005, 2006 Free Software Foundation, Inc. ;; Author: Lynn Slater <lrs@indetech.com> ;; Maintainer: FSF ;; Created: Mon Oct 1 11:42:39 1990 ;; Adapted-By: ESR ;; This file is part of GNU Emacs. ;; GNU Emacs is free software; you can redistribute it and/or modify ;; it under the terms of the GNU General Public License as published by ;; the Free Software Foundation; either version 2, or (at your option) ;; any later version. ;; GNU Emacs is distributed in the hope that it will be useful, ;; but WITHOUT ANY WARRANTY; without even the implied warranty of ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the ;; GNU General Public License for more details. ;; 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., 51 Franklin Street, Fifth Floor, ;; Boston, MA 02110-1301, USA. ;;; Commentary: ;; This file supplies the macro make-help-screen which constructs ;; single character dispatching with browsable help such as that provided ;; by help-for-help. This can be used to make many modes easier to use; for ;; example, the GNU Emacs Empire Tool uses this for every "nested" mode map ;; called from the main mode map. ;; The name of this package was changed from help-screen.el to ;; help-macro.el in order to fit in a 14-character limit. ;;-> *********************** Example of use ********************************* ;;->(make-help-screen help-for-empire-redistribute-map ;;-> "c:civ m:mil p:population f:food ?" ;;-> "You have discovered the GEET redistribution commands ;;-> From here, you can use the following options: ;;-> ;;->c Redistribute civs from overfull sectors into connected underfull ones ;;-> The functions typically named by empire-ideal-civ-fcn control ;;-> based in part on empire-sector-civ-threshold ;;->m Redistribute military using levels given by empire-ideal-mil-fcn ;;->p Redistribute excess population to highways for max pop growth ;;-> Excess is any sector so full babies will not be born. ;;->f Even out food on highways to highway min and leave levels ;;-> This is good to pump max food to all warehouses/dist pts ;;-> ;;-> ;;->Use \\[help-for-empire-redistribute-map] for help on redistribution. ;;->Use \\[help-for-empire-extract-map] for help on data extraction. ;;->Please use \\[describe-key] to find out more about any of the other keys." ;;-> empire-shell-redistribute-map) ;;-> (define-key c-mp "\C-h" 'help-for-empire-redistribute-map) ;;-> (define-key c-mp help-character 'help-for-empire-redistribute-map) ;;; Change Log: ;; ;; 22-Jan-1991 Lynn Slater x2048 ;; Last Modified: Mon Oct 1 11:43:52 1990 #3 (Lynn Slater) ;; documented better ;;; Code: (require 'backquote) ;;;###autoload (defcustom three-step-help nil "*Non-nil means give more info about Help command in three steps. The three steps are simple prompt, prompt with all options, and window listing and describing the options. A value of nil means skip the middle step, so that \\[help-command] \\[help-command] gives the window that lists the options." :type 'boolean :group 'help) (defmacro make-help-screen (fname help-line help-text helped-map) "Construct help-menu function name FNAME. When invoked, FNAME shows HELP-LINE and reads a command using HELPED-MAP. If the command is the help character, FNAME displays HELP-TEXT and continues trying to read a command using HELPED-MAP. If HELP-TEXT contains the sequence `%THIS-KEY%', that is replaced with the key sequence that invoked FNAME. When FNAME finally does get a command, it executes that command and then returns." (let ((doc-fn (intern (concat (symbol-name fname) "-doc")))) `(progn (defun ,doc-fn () ,help-text) (defun ,fname () "Help command." (interactive) (let ((line-prompt (substitute-command-keys ,help-line))) (if three-step-help (message "%s" line-prompt)) (let* ((help-screen (documentation (quote ,doc-fn))) ;; We bind overriding-local-map for very small ;; sections, *excluding* where we switch buffers ;; and where we execute the chosen help command. (local-map (make-sparse-keymap)) (minor-mode-map-alist nil) (prev-frame (selected-frame)) config new-frame key char) (if (string-match "%THIS-KEY%" help-screen) (setq help-screen (replace-match (key-description (substring (this-command-keys) 0 -1)) t t help-screen))) (unwind-protect (progn (setcdr local-map ,helped-map) (define-key local-map [t] 'undefined) ;; Make the scroll bar keep working normally. (define-key local-map [vertical-scroll-bar] (lookup-key global-map [vertical-scroll-bar])) (if three-step-help (progn (setq key (let ((overriding-local-map local-map)) (read-key-sequence nil))) ;; Make the HELP key translate to C-h. (if (lookup-key function-key-map key) (setq key (lookup-key function-key-map key))) (setq char (aref key 0))) (setq char ??)) (if (or (eq char ??) (eq char help-char) (memq char help-event-list)) (progn (setq config (current-window-configuration)) (switch-to-buffer-other-window "*Help*") (and (fboundp 'make-frame) (not (eq (window-frame (selected-window)) prev-frame)) (setq new-frame (window-frame (selected-window)) config nil)) (setq buffer-read-only nil) (let ((inhibit-read-only t)) (erase-buffer) (insert help-screen)) (help-mode) (goto-char (point-min)) (while (or (memq char (append help-event-list (cons help-char '(?? ?\C-v ?\s ?\177 delete backspace vertical-scroll-bar ?\M-v)))) (eq (car-safe char) 'switch-frame) (equal key "\M-v")) (condition-case nil (progn (if (eq (car-safe char) 'switch-frame) (handle-switch-frame char)) (if (memq char '(?\C-v ?\s)) (scroll-up)) (if (or (memq char '(?\177 ?\M-v delete backspace)) (equal key "\M-v")) (scroll-down))) (error nil)) (let ((cursor-in-echo-area t) (overriding-local-map local-map)) (setq key (read-key-sequence (format "Type one of the options listed%s: " (if (pos-visible-in-window-p (point-max)) "" ", or SPACE or DEL to scroll"))) char (aref key 0))) ;; If this is a scroll bar command, just run it. (when (eq char 'vertical-scroll-bar) (command-execute (lookup-key local-map key) nil key))))) ;; We don't need the prompt any more. (message "") ;; Mouse clicks are not part of the help feature, ;; so reexecute them in the standard environment. (if (listp char) (setq unread-command-events (cons char unread-command-events) config nil) (let ((defn (lookup-key local-map key))) (if defn (progn (if config (progn (set-window-configuration config) (setq config nil))) (if new-frame (progn (iconify-frame new-frame) (setq new-frame nil))) (call-interactively defn)) (ding))))) (if new-frame (iconify-frame new-frame)) (if config (set-window-configuration config)))))) ))) (provide 'help-macro) ;;; arch-tag: 59fee949-1686-485a-8a05-83418073e257 ;;; help-macro.el ends here