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Diffstat (limited to 'lisp/derived.el')
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diff --git a/lisp/derived.el b/lisp/derived.el deleted file mode 100644 index 8d152f391bc..00000000000 --- a/lisp/derived.el +++ /dev/null @@ -1,436 +0,0 @@ -;;; derived.el --- allow inheritance of major modes -;;; (formerly mode-clone.el) - -;; Copyright (C) 1993, 1994, 1999, 2003 Free Software Foundation, Inc. - -;; Author: David Megginson (dmeggins@aix1.uottawa.ca) -;; Maintainer: FSF -;; Keywords: extensions - -;; 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., 59 Temple Place - Suite 330, -;; Boston, MA 02111-1307, USA. - -;;; Commentary: - -;; GNU Emacs is already, in a sense, object oriented -- each object -;; (buffer) belongs to a class (major mode), and that class defines -;; the relationship between messages (input events) and methods -;; (commands) by means of a keymap. -;; -;; The only thing missing is a good scheme of inheritance. It is -;; possible to simulate a single level of inheritance with generous -;; use of hooks and a bit of work -- sgml-mode, for example, also runs -;; the hooks for text-mode, and keymaps can inherit from other keymaps -;; -- but generally, each major mode ends up reinventing the wheel. -;; Ideally, someone should redesign all of Emacs's major modes to -;; follow a more conventional object-oriented system: when defining a -;; new major mode, the user should need only to name the existing mode -;; it is most similar to, then list the (few) differences. -;; -;; In the mean time, this package offers most of the advantages of -;; full inheritance with the existing major modes. The macro -;; `define-derived-mode' allows the user to make a variant of an existing -;; major mode, with its own keymap. The new mode will inherit the key -;; bindings of its parent, and will, in fact, run its parent first -;; every time it is called. For example, the commands -;; -;; (define-derived-mode hypertext-mode text-mode "Hypertext" -;; "Major mode for hypertext.\n\n\\{hypertext-mode-map}" -;; (setq case-fold-search nil)) -;; -;; (define-key hypertext-mode-map [down-mouse-3] 'do-hyper-link) -;; -;; will create a function `hypertext-mode' with its own (sparse) -;; keymap `hypertext-mode-map.' The command M-x hypertext-mode will -;; perform the following actions: -;; -;; - run the command (text-mode) to get its default setup -;; - replace the current keymap with 'hypertext-mode-map,' which will -;; inherit from 'text-mode-map'. -;; - replace the current syntax table with -;; 'hypertext-mode-syntax-table', which will borrow its defaults -;; from the current text-mode-syntax-table. -;; - replace the current abbrev table with -;; 'hypertext-mode-abbrev-table', which will borrow its defaults -;; from the current text-mode-abbrev table -;; - change the mode line to read "Hypertext" -;; - assign the value 'hypertext-mode' to the 'major-mode' variable -;; - run the body of commands provided in the macro -- in this case, -;; set the local variable `case-fold-search' to nil. -;; -;; The advantages of this system are threefold. First, text mode is -;; untouched -- if you had added the new keystroke to `text-mode-map,' -;; possibly using hooks, you would have added it to all text buffers -;; -- here, it appears only in hypertext buffers, where it makes -;; sense. Second, it is possible to build even further, and make -;; a derived mode from a derived mode. The commands -;; -;; (define-derived-mode html-mode hypertext-mode "HTML") -;; [various key definitions] -;; -;; will add a new major mode for HTML with very little fuss. -;; -;; Note also the function `derived-mode-p' which can tell if the current -;; mode derives from another. In a hypertext-mode, buffer, for example, -;; (derived-mode-p 'text-mode) would return non-nil. This should always -;; be used in place of (eq major-mode 'text-mode). - -;;; Code: - -(eval-when-compile (require 'cl)) - -;;; PRIVATE: defsubst must be defined before they are first used - -(defsubst derived-mode-hook-name (mode) - "Construct the mode hook name based on mode name MODE." - (intern (concat (symbol-name mode) "-hook"))) - -(defsubst derived-mode-map-name (mode) - "Construct a map name based on a MODE name." - (intern (concat (symbol-name mode) "-map"))) - -(defsubst derived-mode-syntax-table-name (mode) - "Construct a syntax-table name based on a MODE name." - (intern (concat (symbol-name mode) "-syntax-table"))) - -(defsubst derived-mode-abbrev-table-name (mode) - "Construct an abbrev-table name based on a MODE name." - (intern (concat (symbol-name mode) "-abbrev-table"))) - -;; PUBLIC: define a new major mode which inherits from an existing one. - -;;;###autoload -(defmacro define-derived-mode (child parent name &optional docstring &rest body) - "Create a new mode as a variant of an existing mode. - -The arguments to this command are as follow: - -CHILD: the name of the command for the derived mode. -PARENT: the name of the command for the parent mode (e.g. `text-mode') - or nil if there is no parent. -NAME: a string which will appear in the status line (e.g. \"Hypertext\") -DOCSTRING: an optional documentation string--if you do not supply one, - the function will attempt to invent something useful. -BODY: forms to execute just before running the - hooks for the new mode. Do not use `interactive' here. - -BODY can start with a bunch of keyword arguments. The following keyword - arguments are currently understood: -:group GROUP - Declare the customization group that corresponds to this mode. -:syntax-table TABLE - Use TABLE instead of the default. - A nil value means to simply use the same syntax-table as the parent. -:abbrev-table TABLE - Use TABLE instead of the default. - A nil value means to simply use the same abbrev-table as the parent. - -Here is how you could define LaTeX-Thesis mode as a variant of LaTeX mode: - - (define-derived-mode LaTeX-thesis-mode LaTeX-mode \"LaTeX-Thesis\") - -You could then make new key bindings for `LaTeX-thesis-mode-map' -without changing regular LaTeX mode. In this example, BODY is empty, -and DOCSTRING is generated by default. - -On a more complicated level, the following command uses `sgml-mode' as -the parent, and then sets the variable `case-fold-search' to nil: - - (define-derived-mode article-mode sgml-mode \"Article\" - \"Major mode for editing technical articles.\" - (setq case-fold-search nil)) - -Note that if the documentation string had been left out, it would have -been generated automatically, with a reference to the keymap." - (declare (debug (&define name symbolp sexp [&optional stringp] - [&rest keywordp sexp] def-body))) - - (when (and docstring (not (stringp docstring))) - ;; Some trickiness, since what appears to be the docstring may really be - ;; the first element of the body. - (push docstring body) - (setq docstring nil)) - - (when (eq parent 'fundamental-mode) (setq parent nil)) - - (let ((map (derived-mode-map-name child)) - (syntax (derived-mode-syntax-table-name child)) - (abbrev (derived-mode-abbrev-table-name child)) - (declare-abbrev t) - (declare-syntax t) - (hook (derived-mode-hook-name child)) - (group nil)) - - ;; Process the keyword args. - (while (keywordp (car body)) - (case (pop body) - (:group (setq group (pop body))) - (:abbrev-table (setq abbrev (pop body)) (setq declare-abbrev nil)) - (:syntax-table (setq syntax (pop body)) (setq declare-syntax nil)) - (t (pop body)))) - - (setq docstring (derived-mode-make-docstring - parent child docstring syntax abbrev)) - - `(progn - (defvar ,map (make-sparse-keymap)) - ,(if declare-syntax - `(defvar ,syntax (make-syntax-table))) - ,(if declare-abbrev - `(defvar ,abbrev - (progn (define-abbrev-table ',abbrev nil) ,abbrev))) - (put ',child 'derived-mode-parent ',parent) - ,(if group `(put ',child 'custom-mode-group ,group)) - - (defun ,child () - ,docstring - (interactive) - ; Run the parent. - (delay-mode-hooks - - (,(or parent 'kill-all-local-variables)) - ; Identify the child mode. - (setq major-mode (quote ,child)) - (setq mode-name ,name) - ; Identify special modes. - ,(when parent - `(progn - (if (get (quote ,parent) 'mode-class) - (put (quote ,child) 'mode-class - (get (quote ,parent) 'mode-class))) - ; Set up maps and tables. - (unless (keymap-parent ,map) - (set-keymap-parent ,map (current-local-map))) - ,(when declare-syntax - `(let ((parent (char-table-parent ,syntax))) - (unless (and parent - (not (eq parent (standard-syntax-table)))) - (set-char-table-parent ,syntax (syntax-table))))))) - - (use-local-map ,map) - ,(when syntax `(set-syntax-table ,syntax)) - ,(when abbrev `(setq local-abbrev-table ,abbrev)) - ; Splice in the body (if any). - ,@body - ) - ;; Run the hooks, if any. - ;; Make the generated code work in older Emacs versions - ;; that do not yet have run-mode-hooks. - (if (fboundp 'run-mode-hooks) - (run-mode-hooks ',hook) - (run-hooks ',hook)))))) - -;; PUBLIC: find the ultimate class of a derived mode. - -(defun derived-mode-class (mode) - "Find the class of a major MODE. -A mode's class is the first ancestor which is NOT a derived mode. -Use the `derived-mode-parent' property of the symbol to trace backwards. -Since major-modes might all derive from `fundamental-mode', this function -is not very useful." - (while (get mode 'derived-mode-parent) - (setq mode (get mode 'derived-mode-parent))) - mode) -(make-obsolete 'derived-mode-class 'derived-mode-p "21.4") - - -;;; PRIVATE - -(defun derived-mode-make-docstring (parent child &optional - docstring syntax abbrev) - "Construct a docstring for a new mode if none is provided." - - (let ((map (derived-mode-map-name child)) - (hook (derived-mode-hook-name child))) - - (unless (stringp docstring) - ;; Use a default docstring. - (setq docstring - (if (null parent) - (format "Major-mode. -Uses keymap `%s', abbrev table `%s' and syntax-table `%s'." map abbrev syntax) - (format "Major mode derived from `%s' by `define-derived-mode'. -It inherits all of the parent's attributes, but has its own keymap, -abbrev table and syntax table: - - `%s', `%s' and `%s' - -which more-or-less shadow %s's corresponding tables." - parent map abbrev syntax parent)))) - - (unless (string-match (regexp-quote (symbol-name hook)) docstring) - ;; Make sure the docstring mentions the mode's hook. - (setq docstring - (concat docstring - (if (null parent) - "\n\nThis mode " - (concat - "\n\nIn addition to any hooks its parent mode " - (if (string-match (regexp-quote (format "`%s'" parent)) - docstring) nil - (format "`%s' " parent)) - "might have run,\nthis mode ")) - (format "runs the hook `%s'" hook) - ", as the final step\nduring initialization."))) - - (unless (string-match "\\\\[{[]" docstring) - ;; And don't forget to put the mode's keymap. - (setq docstring (concat docstring "\n\n\\{" (symbol-name map) "}"))) - - docstring)) - - -;;; OBSOLETE -;; The functions below are only provided for backward compatibility with -;; code byte-compiled with versions of derived.el prior to Emacs-21. - -(defsubst derived-mode-setup-function-name (mode) - "Construct a setup-function name based on a MODE name." - (intern (concat (symbol-name mode) "-setup"))) - - -;; Utility functions for defining a derived mode. - -;;;###autoload -(defun derived-mode-init-mode-variables (mode) - "Initialise variables for a new MODE. -Right now, if they don't already exist, set up a blank keymap, an -empty syntax table, and an empty abbrev table -- these will be merged -the first time the mode is used." - - (if (boundp (derived-mode-map-name mode)) - t - (eval `(defvar ,(derived-mode-map-name mode) - (make-sparse-keymap) - ,(format "Keymap for %s." mode))) - (put (derived-mode-map-name mode) 'derived-mode-unmerged t)) - - (if (boundp (derived-mode-syntax-table-name mode)) - t - (eval `(defvar ,(derived-mode-syntax-table-name mode) - ;; Make a syntax table which doesn't specify anything - ;; for any char. Valid data will be merged in by - ;; derived-mode-merge-syntax-tables. - (make-char-table 'syntax-table nil) - ,(format "Syntax table for %s." mode))) - (put (derived-mode-syntax-table-name mode) 'derived-mode-unmerged t)) - - (if (boundp (derived-mode-abbrev-table-name mode)) - t - (eval `(defvar ,(derived-mode-abbrev-table-name mode) - (progn - (define-abbrev-table (derived-mode-abbrev-table-name mode) nil) - (make-abbrev-table)) - ,(format "Abbrev table for %s." mode))))) - -;; Utility functions for running a derived mode. - -(defun derived-mode-set-keymap (mode) - "Set the keymap of the new MODE, maybe merging with the parent." - (let* ((map-name (derived-mode-map-name mode)) - (new-map (eval map-name)) - (old-map (current-local-map))) - (and old-map - (get map-name 'derived-mode-unmerged) - (derived-mode-merge-keymaps old-map new-map)) - (put map-name 'derived-mode-unmerged nil) - (use-local-map new-map))) - -(defun derived-mode-set-syntax-table (mode) - "Set the syntax table of the new MODE, maybe merging with the parent." - (let* ((table-name (derived-mode-syntax-table-name mode)) - (old-table (syntax-table)) - (new-table (eval table-name))) - (if (get table-name 'derived-mode-unmerged) - (derived-mode-merge-syntax-tables old-table new-table)) - (put table-name 'derived-mode-unmerged nil) - (set-syntax-table new-table))) - -(defun derived-mode-set-abbrev-table (mode) - "Set the abbrev table for MODE if it exists. -Always merge its parent into it, since the merge is non-destructive." - (let* ((table-name (derived-mode-abbrev-table-name mode)) - (old-table local-abbrev-table) - (new-table (eval table-name))) - (derived-mode-merge-abbrev-tables old-table new-table) - (setq local-abbrev-table new-table))) - -;;;(defun derived-mode-run-setup-function (mode) -;;; "Run the setup function if it exists." - -;;; (let ((fname (derived-mode-setup-function-name mode))) -;;; (if (fboundp fname) -;;; (funcall fname)))) - -(defun derived-mode-run-hooks (mode) - "Run the mode hook for MODE." - (let ((hooks-name (derived-mode-hook-name mode))) - (if (boundp hooks-name) - (run-hooks hooks-name)))) - -;; Functions to merge maps and tables. - -(defun derived-mode-merge-keymaps (old new) - "Merge an OLD keymap into a NEW one. -The old keymap is set to be the last cdr of the new one, so that there will -be automatic inheritance." - ;; ?? Can this just use `set-keymap-parent'? - (let ((tail new)) - ;; Scan the NEW map for prefix keys. - (while (consp tail) - (and (consp (car tail)) - (let* ((key (vector (car (car tail)))) - (subnew (lookup-key new key)) - (subold (lookup-key old key))) - ;; If KEY is a prefix key in both OLD and NEW, merge them. - (and (keymapp subnew) (keymapp subold) - (derived-mode-merge-keymaps subold subnew)))) - (and (vectorp (car tail)) - ;; Search a vector of ASCII char bindings for prefix keys. - (let ((i (1- (length (car tail))))) - (while (>= i 0) - (let* ((key (vector i)) - (subnew (lookup-key new key)) - (subold (lookup-key old key))) - ;; If KEY is a prefix key in both OLD and NEW, merge them. - (and (keymapp subnew) (keymapp subold) - (derived-mode-merge-keymaps subold subnew))) - (setq i (1- i))))) - (setq tail (cdr tail)))) - (setcdr (nthcdr (1- (length new)) new) old)) - -(defun derived-mode-merge-syntax-tables (old new) - "Merge an OLD syntax table into a NEW one. -Where the new table already has an entry, nothing is copied from the old one." - (set-char-table-parent new old)) - -;; Merge an old abbrev table into a new one. -;; This function requires internal knowledge of how abbrev tables work, -;; presuming that they are obarrays with the abbrev as the symbol, the expansion -;; as the value of the symbol, and the hook as the function definition. -(defun derived-mode-merge-abbrev-tables (old new) - (if old - (mapatoms - (lambda (symbol) - (or (intern-soft (symbol-name symbol) new) - (define-abbrev new (symbol-name symbol) - (symbol-value symbol) (symbol-function symbol)))) - old))) - -(provide 'derived) - -;;; derived.el ends here |