X-Git-Url: https://git.hcoop.net/bpt/emacs.git/blobdiff_plain/e4c37df7165b7679611f368dcdf59381b6483c57..e0ecbf5c163626f2580ca3500f49e8c439de2fb1:/lisp/paren.el

diff --git a/lisp/paren.el b/lisp/paren.el
dissimilarity index 66%
index f1e66567b0..40e99bea0e 100644
--- a/lisp/paren.el
+++ b/lisp/paren.el
@@ -1,96 +1,229 @@
-;;; paren.el --- highlight matching paren.
-;; Copyright (C) 1993 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, 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 show-paren-overlay nil)
-
-;; Find the place to show, if there is one,
-;; and show it until input arrives.
-(defun show-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 show.
-	(if mismatch
-	    (progn
-	      (message "Paren mismatch")
-;;;	      (setq pos nil)
-	      ))))
-    (cond (pos
-	   (if show-paren-overlay
-	       (move-overlay show-paren-overlay (- pos dir) pos)
-	     (setq show-paren-overlay
-		   (make-overlay (- pos dir) pos)))
-	   (overlay-put show-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 show-paren-overlay
-;;;			  'face
-;;;			  (if (overlay-get show-paren-overlay
-;;;					   'face)
-;;;			      nil face)))
-	   )
-	  (t
-	   (and show-paren-overlay (overlay-buffer show-paren-overlay)
-		(delete-overlay show-paren-overlay))))))
-
-(add-hook 'post-command-hook 'show-paren-command-hook)
-
-(provide 'paren)
-
-;;; paren.el ends here
+;;; paren.el --- highlight matching paren.
+
+;; Copyright (C) 1993, 1996 Free Software Foundation, Inc.
+
+;; Author: rms@gnu.org
+;; 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-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-priority 1000
+  "*Priority of paren highlighting overlays."
+  :type 'integer
+  :group 'paren-showing
+  :version "21.1")
+  
+(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
+(define-minor-mode show-paren-mode
+  "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."
+  :global t :group 'paren-showing
+    ;; Turn off the usual paren-matching method
+    ;; when this one is turned on.
+    (if (local-variable-p 'show-paren-mode)
+	(make-local-variable 'blink-matching-paren-on-screen)
+      (kill-local-variable 'blink-matching-paren-on-screen))
+    (setq blink-matching-paren-on-screen (not show-paren-mode))
+
+    ;; Now enable or disable the mechanism.
+    ;; First get rid of the old idle timer.
+    (if show-paren-idle-timer
+	(cancel-timer show-paren-idle-timer))
+    (setq show-paren-idle-timer nil)
+    ;; If show-paren-mode is enabled in some buffer now,
+    ;; set up a new timer.
+    (when (memq t (mapcar (lambda (buffer)
+			    (with-current-buffer buffer
+			      show-paren-mode))
+			  (buffer-list)))
+      (setq show-paren-idle-timer (run-with-idle-timer
+				   show-paren-delay t
+				   'show-paren-function)))
+    (unless show-paren-mode
+      (and show-paren-overlay
+	   (eq (overlay-buffer show-paren-overlay) (current-buffer))
+	   (delete-overlay show-paren-overlay))
+      (and show-paren-overlay-1
+	   (eq (overlay-buffer show-paren-overlay-1) (current-buffer))
+	   (delete-overlay show-paren-overlay-1))))
+
+;; Find the place to show, if there is one,
+;; and show it until input arrives.
+(defun show-paren-function ()
+  (if show-paren-mode
+      (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 'priority show-paren-priority)
+	      (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 'priority show-paren-priority)
+	  (overlay-put show-paren-overlay 'face face)))
+    ;; show-paren-mode is nil in this buffer.
+    (and show-paren-overlay
+	 (delete-overlay show-paren-overlay))
+    (and show-paren-overlay-1
+	 (delete-overlay show-paren-overlay-1))))
+
+(provide 'paren)
+
+;;; paren.el ends here