-;;; paren.el --- highlight matching paren.
-;; Copyright (C) 1993 Free Software Foundation, Inc.
-
-;; 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, 675 Mass Ave, Cambridge, MA 02139, USA.
-
-;;; Commentary:
-
-;; Load this and it will display highlighting on whatever
-;; paren matches the one before or after point.
-
-;;; Code:
-
-(defvar blink-paren-overlay nil)
-
-;; Find the place to blink, if there is one,
-;; and blink it until input arrives.
-(defun blink-paren-command-hook ()
- (let (pos dir mismatch (oldpos (point))
- (face (if (face-equal 'highlight 'region)
- 'underline 'highlight)))
- (cond ((eq (char-syntax (following-char)) ?\()
- (setq dir 1))
- ((eq (char-syntax (preceding-char)) ?\))
- (setq dir -1)))
- (save-excursion
- (save-restriction
- ;; Determine the range within which to look for a match.
- (if blink-matching-paren-distance
- (narrow-to-region (max (point-min)
- (- (point) blink-matching-paren-distance))
- (min (point-max)
- (+ (point) blink-matching-paren-distance))))
- ;; Scan across one sexp within that range.
- (condition-case ()
- (setq pos (scan-sexps (point) dir))
- (error nil))
- ;; See if the "matching" paren is the right kind of paren
- ;; to match the one we started at.
- (if pos
- (let ((beg (min pos oldpos)) (end (max pos oldpos)))
- (and (/= (char-syntax (char-after beg)) ?\$)
- (setq mismatch
- (/= (char-after (1- end))
- (logand (lsh (aref (syntax-table)
- (char-after beg))
- -8)
- 255))))))
- ;; If they don't properly match, don't blink.
- (if mismatch
- (setq pos nil))))
- (cond (pos
- (if blink-paren-overlay
- (move-overlay blink-paren-overlay (- pos dir) pos)
- (setq blink-paren-overlay
- (make-overlay (- pos dir) pos)))
- (overlay-put blink-paren-overlay 'face face)
-;;; This is code to blink the highlighting.
-;;; It is desirable to avoid this because
-;;; it would interfere with auto-save and gc when idle.
-;;; (while (sit-for 1)
-;;; (overlay-put blink-paren-overlay
-;;; 'face
-;;; (if (overlay-get blink-paren-overlay
-;;; 'face)
-;;; nil face)))
- )
- (t
- (delete-overlay blink-paren-overlay)))))
-
-(add-hook 'post-command-hook 'blink-paren-command-hook)
-
+;;; paren.el --- highlight matching paren.
+
+;; Copyright (C) 1993, 1996 Free Software Foundation, Inc.
+
+;; Author: rms@gnu.ai.mit.edu
+;; Maintainer: FSF
+;; Keywords: languages, faces
+
+;; 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:
+
+;; Load this and it will display highlighting on whatever
+;; paren matches the one before or after point.
+
+;;; Code:
+
+(defgroup paren-showing nil
+ "Showing (un)matching of parens and expressions."
+ :prefix "show-paren-"
+ :group 'paren-matching)
+
+;; This is the overlay used to highlight the matching paren.
+(defvar show-paren-overlay nil)
+;; This is the overlay used to highlight the closeparen right before point.
+(defvar show-paren-overlay-1 nil)
+
+(defcustom show-paren-mode nil
+ "Toggle Show Paren mode.
+When Show Paren mode is enabled, any matching parenthesis is highlighted
+after `show-paren-delay' seconds of Emacs idle time.
+You must modify via \\[customize] for this variable to have an effect."
+ :set (lambda (symbol value)
+ (show-paren-mode (or value 0)))
+ :initialize 'custom-initialize-default
+ :type 'boolean
+ :group 'paren-showing
+ :require 'paren)
+
+(defcustom show-paren-style 'parenthesis
+ "*Style used when showing a matching paren.
+Valid styles are `parenthesis' (meaning show the matching paren),
+`expression' (meaning show the entire expression enclosed by the paren) and
+`mixed' (meaning show the matching paren if it is visible, and the expression
+otherwise)."
+ :type '(choice (const parenthesis) (const expression) (const mixed))
+ :group 'paren-showing)
+
+(defcustom show-paren-delay
+ (if (featurep 'lisp-float-type) (/ (float 1) (float 8)) 1)
+ "*Time in seconds to delay before showing a matching paren."
+ :type '(number :tag "seconds")
+ :group 'paren-showing)
+
+(defcustom show-paren-ring-bell-on-mismatch nil
+ "*If non-nil, beep if mismatched paren is detected."
+ :type 'boolean
+ :group 'paren-showing
+ :version "20.3")
+
+(defface show-paren-match-face
+ '((((class color)) (:background "turquoise"))
+ (t (:background "gray")))
+ "Show Paren mode face used for a matching paren."
+ :group 'faces
+ :group 'paren-showing)
+
+(defface show-paren-mismatch-face
+ '((((class color)) (:foreground "white" :background "purple"))
+ (t (:reverse-video t)))
+ "Show Paren mode face used for a mismatching paren."
+ :group 'faces
+ :group 'paren-showing)
+
+(defvar show-paren-idle-timer nil)
+
+;;;###autoload
+(defun show-paren-mode (&optional arg)
+ "Toggle Show Paren mode.
+With prefix ARG, turn Show Paren mode on if and only if ARG is positive.
+Returns the new status of Show Paren mode (non-nil means on).
+
+When Show Paren mode is enabled, any matching parenthesis is highlighted
+in `show-paren-style' after `show-paren-delay' seconds of Emacs idle time."
+ (interactive "P")
+ (when window-system
+ (let ((on-p (if arg
+ (> (prefix-numeric-value arg) 0)
+ (not show-paren-mode))))
+ (setq blink-matching-paren-on-screen (not on-p))
+ (when show-paren-idle-timer
+ (cancel-timer show-paren-idle-timer))
+ (if on-p
+ (setq show-paren-idle-timer (run-with-idle-timer
+ show-paren-delay t
+ 'show-paren-function))
+ (and show-paren-overlay (overlay-buffer show-paren-overlay)
+ (delete-overlay show-paren-overlay))
+ (and show-paren-overlay-1 (overlay-buffer show-paren-overlay-1)
+ (delete-overlay show-paren-overlay-1)))
+ (setq show-paren-mode on-p))))
+
+;; Find the place to show, if there is one,
+;; and show it until input arrives.
+(defun show-paren-function ()
+ ;; Do nothing if no window system to display results with.
+ ;; Do nothing if executing keyboard macro.
+ ;; Do nothing if input is pending.
+ (when window-system
+ (let (pos dir mismatch face (oldpos (point)))
+ (cond ((eq (char-syntax (preceding-char)) ?\))
+ (setq dir -1))
+ ((eq (char-syntax (following-char)) ?\()
+ (setq dir 1)))
+ ;;
+ ;; Find the other end of the sexp.
+ (when dir
+ (save-excursion
+ (save-restriction
+ ;; Determine the range within which to look for a match.
+ (when blink-matching-paren-distance
+ (narrow-to-region
+ (max (point-min) (- (point) blink-matching-paren-distance))
+ (min (point-max) (+ (point) blink-matching-paren-distance))))
+ ;; Scan across one sexp within that range.
+ ;; Errors or nil mean there is a mismatch.
+ (condition-case ()
+ (setq pos (scan-sexps (point) dir))
+ (error (setq pos t mismatch t)))
+ ;; If found a "matching" paren, see if it is the right
+ ;; kind of paren to match the one we started at.
+ (when (integerp pos)
+ (let ((beg (min pos oldpos)) (end (max pos oldpos)))
+ (when (/= (char-syntax (char-after beg)) ?\$)
+ (setq mismatch
+ (not (eq (char-before end)
+ ;; This can give nil.
+ (matching-paren (char-after beg)))))))))))
+ ;;
+ ;; Highlight the other end of the sexp, or unhighlight if none.
+ (if (not pos)
+ (progn
+ ;; If not at a paren that has a match,
+ ;; turn off any previous paren highlighting.
+ (and show-paren-overlay (overlay-buffer show-paren-overlay)
+ (delete-overlay show-paren-overlay))
+ (and show-paren-overlay-1 (overlay-buffer show-paren-overlay-1)
+ (delete-overlay show-paren-overlay-1)))
+ ;;
+ ;; Use the correct face.
+ (if mismatch
+ (progn
+ (if show-paren-ring-bell-on-mismatch
+ (beep))
+ (setq face 'show-paren-mismatch-face))
+ (setq face 'show-paren-match-face))
+ ;;
+ ;; If matching backwards, highlight the closeparen
+ ;; before point as well as its matching open.
+ ;; If matching forward, and the openparen is unbalanced,
+ ;; highlight the paren at point to indicate misbalance.
+ ;; Otherwise, turn off any such highlighting.
+ (if (and (= dir 1) (integerp pos))
+ (when (and show-paren-overlay-1
+ (overlay-buffer show-paren-overlay-1))
+ (delete-overlay show-paren-overlay-1))
+ (let ((from (if (= dir 1)
+ (point)
+ (forward-point -1)))
+ (to (if (= dir 1)
+ (forward-point 1)
+ (point))))
+ (if show-paren-overlay-1
+ (move-overlay show-paren-overlay-1 from to (current-buffer))
+ (setq show-paren-overlay-1 (make-overlay from to)))
+ ;; Always set the overlay face, since it varies.
+ (overlay-put show-paren-overlay-1 'face face)))
+ ;;
+ ;; Turn on highlighting for the matching paren, if found.
+ ;; If it's an unmatched paren, turn off any such highlighting.
+ (unless (integerp pos)
+ (delete-overlay show-paren-overlay))
+ (let ((to (if (or (eq show-paren-style 'expression)
+ (and (eq show-paren-style 'mixed)
+ (not (pos-visible-in-window-p pos))))
+ (point)
+ pos))
+ (from (if (or (eq show-paren-style 'expression)
+ (and (eq show-paren-style 'mixed)
+ (not (pos-visible-in-window-p pos))))
+ pos
+ (save-excursion
+ (goto-char pos)
+ (forward-point (- dir))))))
+ (if show-paren-overlay
+ (move-overlay show-paren-overlay from to (current-buffer))
+ (setq show-paren-overlay (make-overlay from to))))
+ ;;
+ ;; Always set the overlay face, since it varies.
+ (overlay-put show-paren-overlay 'face face)))))
+
+(provide 'paren)
+
+(if show-paren-mode
+ (show-paren-mode t))
+
+;;; paren.el ends here
HCoop / bpt / emacs.git / blobdiff