mirror of
https://git.savannah.gnu.org/git/emacs.git
synced 2024-12-27 10:54:40 +00:00
297 lines
11 KiB
EmacsLisp
297 lines
11 KiB
EmacsLisp
;;; paren.el --- highlight matching paren
|
|
|
|
;; Copyright (C) 1993, 1996, 2001-2015 Free Software Foundation, Inc.
|
|
|
|
;; Author: rms@gnu.org
|
|
;; Maintainer: emacs-devel@gnu.org
|
|
;; 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 3 of the License, 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. If not, see <http://www.gnu.org/licenses/>.
|
|
|
|
;;; Commentary:
|
|
|
|
;; Put this into your ~/.emacs:
|
|
|
|
;; (show-paren-mode t)
|
|
|
|
;; 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)
|
|
|
|
(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)))
|
|
|
|
(defcustom show-paren-delay 0.125
|
|
"Time in seconds to delay before showing a matching paren.
|
|
If you change this without using customize while `show-paren-mode' is
|
|
active, you must toggle the mode off and on again for this to take effect."
|
|
:type '(number :tag "seconds")
|
|
:initialize 'custom-initialize-default
|
|
:set (lambda (sym val)
|
|
(if (not show-paren-mode)
|
|
(set sym val)
|
|
(show-paren-mode -1)
|
|
(set sym val)
|
|
(show-paren-mode 1))))
|
|
|
|
(defcustom show-paren-priority 1000
|
|
"Priority of paren highlighting overlays."
|
|
:type 'integer
|
|
:version "21.1")
|
|
|
|
(defcustom show-paren-ring-bell-on-mismatch nil
|
|
"If non-nil, beep if mismatched paren is detected."
|
|
:type 'boolean
|
|
:version "20.3")
|
|
|
|
(defcustom show-paren-when-point-inside-paren nil
|
|
"If non-nil, show parens when point is just inside one.
|
|
This will only be done when point isn't also just outside a paren."
|
|
:type 'boolean
|
|
:version "25.1")
|
|
|
|
(defcustom show-paren-when-point-in-periphery nil
|
|
"If non-nil, show parens when point is in the line's periphery.
|
|
The periphery is at the beginning or end of a line or in any
|
|
whitespace there."
|
|
:type 'boolean
|
|
:version "25.1")
|
|
|
|
(define-obsolete-face-alias 'show-paren-match-face 'show-paren-match "22.1")
|
|
|
|
(define-obsolete-face-alias 'show-paren-mismatch-face
|
|
'show-paren-mismatch "22.1")
|
|
|
|
(defcustom show-paren-highlight-openparen t
|
|
"Non-nil turns on openparen highlighting when matching forward."
|
|
:type 'boolean)
|
|
|
|
(defvar show-paren--idle-timer nil)
|
|
(defvar show-paren--overlay
|
|
(let ((ol (make-overlay (point) (point) nil t))) (delete-overlay ol) ol)
|
|
"Overlay used to highlight the matching paren.")
|
|
(defvar show-paren--overlay-1
|
|
(let ((ol (make-overlay (point) (point) nil t))) (delete-overlay ol) ol)
|
|
"Overlay used to highlight the paren at point.")
|
|
|
|
|
|
;;;###autoload
|
|
(define-minor-mode show-paren-mode
|
|
"Toggle visualization of matching parens (Show Paren mode).
|
|
With a prefix argument ARG, enable Show Paren mode if ARG is
|
|
positive, and disable it otherwise. If called from Lisp, enable
|
|
the mode if ARG is omitted or nil.
|
|
|
|
Show Paren mode is a global minor mode. When enabled, any
|
|
matching parenthesis is highlighted in `show-paren-style' after
|
|
`show-paren-delay' seconds of Emacs idle time."
|
|
:global t :group 'paren-showing
|
|
;; Enable or disable the mechanism.
|
|
;; First get rid of the old idle timer.
|
|
(when show-paren--idle-timer
|
|
(cancel-timer show-paren--idle-timer)
|
|
(setq show-paren--idle-timer nil))
|
|
(setq show-paren--idle-timer (run-with-idle-timer
|
|
show-paren-delay t
|
|
#'show-paren-function))
|
|
(unless show-paren-mode
|
|
(delete-overlay show-paren--overlay)
|
|
(delete-overlay show-paren--overlay-1)))
|
|
|
|
(defun show-paren--unescaped-p (pos)
|
|
"Determine whether the paren after POS is unescaped."
|
|
(save-excursion
|
|
(goto-char pos)
|
|
(= (logand (skip-syntax-backward "/\\") 1) 0)))
|
|
|
|
(defun show-paren--categorize-paren (pos)
|
|
"Determine whether the character after POS has paren syntax,
|
|
and if so, return a cons (DIR . OUTSIDE), where DIR is 1 for an
|
|
open paren, -1 for a close paren, and OUTSIDE is the buffer
|
|
position of the outside of the paren. If the character isn't a
|
|
paren, or it is an escaped paren, return nil."
|
|
(cond
|
|
((and (eq (syntax-class (syntax-after pos)) 4)
|
|
(show-paren--unescaped-p pos))
|
|
(cons 1 pos))
|
|
((and (eq (syntax-class (syntax-after pos)) 5)
|
|
(show-paren--unescaped-p pos))
|
|
(cons -1 (1+ pos)))))
|
|
|
|
(defun show-paren--locate-near-paren ()
|
|
"Locate an unescaped paren \"near\" point to show.
|
|
If one is found, return the cons (DIR . OUTSIDE), where DIR is 1
|
|
for an open paren, -1 for a close paren, and OUTSIDE is the buffer
|
|
position of the outside of the paren. Otherwise return nil."
|
|
(let* ((ind-pos (save-excursion (back-to-indentation) (point)))
|
|
(eol-pos
|
|
(save-excursion
|
|
(end-of-line) (skip-chars-backward " \t" ind-pos) (point)))
|
|
(before (show-paren--categorize-paren (1- (point))))
|
|
(after (show-paren--categorize-paren (point))))
|
|
(cond
|
|
;; Point is immediately outside a paren.
|
|
((eq (car before) -1) before)
|
|
((eq (car after) 1) after)
|
|
;; Point is immediately inside a paren.
|
|
((and show-paren-when-point-inside-paren before))
|
|
((and show-paren-when-point-inside-paren after))
|
|
;; Point is in the whitespace before the code.
|
|
((and show-paren-when-point-in-periphery
|
|
(<= (point) ind-pos))
|
|
(or (show-paren--categorize-paren ind-pos)
|
|
(show-paren--categorize-paren (1- eol-pos))))
|
|
;; Point is in the whitespace after the code.
|
|
((and show-paren-when-point-in-periphery
|
|
(>= (point) eol-pos))
|
|
(show-paren--categorize-paren (1- eol-pos))))))
|
|
|
|
(defvar show-paren-data-function #'show-paren--default
|
|
"Function to find the opener/closer \"near\" point and its match.
|
|
The function is called with no argument and should return either nil
|
|
if there's no opener/closer near point, or a list of the form
|
|
\(HERE-BEG HERE-END THERE-BEG THERE-END MISMATCH)
|
|
Where HERE-BEG..HERE-END is expected to be near point.")
|
|
|
|
(defun show-paren--default ()
|
|
(let* ((temp (show-paren--locate-near-paren))
|
|
(dir (car temp))
|
|
(outside (cdr temp))
|
|
pos mismatch here-beg here-end)
|
|
;;
|
|
;; Find the other end of the sexp.
|
|
(when dir
|
|
(setq here-beg (if (eq dir 1) outside (1- outside))
|
|
here-end (if (eq dir 1) (1+ outside) outside))
|
|
(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 outside dir))
|
|
(error (setq pos t mismatch t)))
|
|
;; Move back the other way and verify we get back to the
|
|
;; starting point. If not, these two parens don't really match.
|
|
;; Maybe the one at point is escaped and doesn't really count,
|
|
;; or one is inside a comment.
|
|
(when (integerp pos)
|
|
(unless (condition-case ()
|
|
(eq outside (scan-sexps pos (- dir)))
|
|
(error nil))
|
|
(setq pos nil)))
|
|
;; If found a "matching" paren, see if it is the right
|
|
;; kind of paren to match the one we started at.
|
|
(if (not (integerp pos))
|
|
(if mismatch (list here-beg here-end nil nil t))
|
|
(let ((beg (min pos outside)) (end (max pos outside)))
|
|
(unless (eq (syntax-class (syntax-after beg)) 8)
|
|
(setq mismatch
|
|
(not (or (eq (char-before end)
|
|
;; This can give nil.
|
|
(cdr (syntax-after beg)))
|
|
(eq (char-after beg)
|
|
;; This can give nil.
|
|
(cdr (syntax-after (1- end))))
|
|
;; The cdr might hold a new paren-class
|
|
;; info rather than a matching-char info,
|
|
;; in which case the two CDRs should match.
|
|
(eq (cdr (syntax-after (1- end)))
|
|
(cdr (syntax-after beg)))))))
|
|
(list here-beg here-end
|
|
(if (= dir 1) (1- pos) pos)
|
|
(if (= dir 1) pos (1+ pos))
|
|
mismatch)))))))
|
|
|
|
;; Find the place to show, if there is one,
|
|
;; and show it until input arrives.
|
|
(defun show-paren-function ()
|
|
(let ((data (and show-paren-mode (funcall show-paren-data-function))))
|
|
(if (not data)
|
|
(progn
|
|
;; If show-paren-mode is nil in this buffer or if not at a paren that
|
|
;; has a match, turn off any previous paren highlighting.
|
|
(delete-overlay show-paren--overlay)
|
|
(delete-overlay show-paren--overlay-1))
|
|
|
|
;; Found something to highlight.
|
|
(let* ((here-beg (nth 0 data))
|
|
(here-end (nth 1 data))
|
|
(there-beg (nth 2 data))
|
|
(there-end (nth 3 data))
|
|
(mismatch (nth 4 data))
|
|
(face
|
|
(if mismatch
|
|
(progn
|
|
(if show-paren-ring-bell-on-mismatch
|
|
(beep))
|
|
'show-paren-mismatch)
|
|
'show-paren-match)))
|
|
;;
|
|
;; 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 (or (not here-beg)
|
|
(and (not show-paren-highlight-openparen)
|
|
(> here-end (point))
|
|
(<= here-beg (point))
|
|
(integerp there-beg)))
|
|
(delete-overlay show-paren--overlay-1)
|
|
(move-overlay show-paren--overlay-1
|
|
here-beg here-end (current-buffer))
|
|
;; 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.
|
|
(if (not there-beg)
|
|
(delete-overlay show-paren--overlay)
|
|
(if (or (eq show-paren-style 'expression)
|
|
(and (eq show-paren-style 'mixed)
|
|
(let ((closest (if (< there-beg here-beg)
|
|
(1- there-end) (1+ there-beg))))
|
|
(not (pos-visible-in-window-p closest)))))
|
|
(move-overlay show-paren--overlay
|
|
(if (< there-beg here-beg) here-end here-beg)
|
|
(if (< there-beg here-beg) there-beg there-end)
|
|
(current-buffer))
|
|
(move-overlay show-paren--overlay
|
|
there-beg there-end (current-buffer)))
|
|
;; Always set the overlay face, since it varies.
|
|
(overlay-put show-paren--overlay 'priority show-paren-priority)
|
|
(overlay-put show-paren--overlay 'face face))))))
|
|
|
|
(provide 'paren)
|
|
|
|
;;; paren.el ends here
|