-;;; electric.el --- window maker and Command loop for `electric' modes
-
-;; Copyright (C) 1985-1986, 1995, 2001-2013 Free Software Foundation,
-;; Inc.
-
-;; Author: K. Shane Hartman
-;; 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 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:
-
-;; "Electric" has been used in Emacs to refer to different things.
-;; Among them:
-;;
-;; - electric modes and buffers: modes that typically pop-up in a modal kind of
-;; way a transient buffer that automatically disappears as soon as the user
-;; is done with it.
-;;
-;; - electric keys: self inserting keys which additionally perform some side
-;; operation which happens to be often convenient at that time. Examples of
-;; such side operations are: reindenting code, inserting a newline,
-;; ... auto-fill-mode and abbrev-mode can be considered as built-in forms of
-;; electric key behavior.
-
-;;; Code:
-
-;; This loop is the guts for non-standard modes which retain control
-;; until some event occurs. It is a `do-forever', the only way out is
-;; to throw. It assumes that you have set up the keymap, window, and
-;; everything else: all it does is read commands and execute them -
-;; providing error messages should one occur (if there is no loop
-;; function - which see). The required argument is a tag which should
-;; expect a value of nil if the user decides to punt. The second
-;; argument is the prompt to be used: if nil, use "->", if 'noprompt,
-;; don't use a prompt, if a string, use that string as prompt, and if
-;; a function of no variable, it will be evaluated in every iteration
-;; of the loop and its return value, which can be nil, 'noprompt or a
-;; string, will be used as prompt. Given third argument non-nil, it
-;; INHIBITS quitting unless the user types C-g at toplevel. This is
-;; so user can do things like C-u C-g and not get thrown out. Fourth
-;; argument, if non-nil, should be a function of two arguments which
-;; is called after every command is executed. The fifth argument, if
-;; provided, is the state variable for the function. If the
-;; loop-function gets an error, the loop will abort WITHOUT throwing
-;; (moral: use unwind-protect around call to this function for any
-;; critical stuff). The second argument for the loop function is the
-;; conditions for any error that occurred or nil if none.
-
-(defun Electric-command-loop (return-tag
- &optional prompt inhibit-quitting
- loop-function loop-state)
-
- (let (cmd
- (err nil)
- (inhibit-quit inhibit-quitting)
- (prompt-string prompt))
- (while t
- (if (functionp prompt)
- (setq prompt-string (funcall prompt)))
- (if (not (stringp prompt-string))
- (setq prompt-string (unless (eq prompt-string 'noprompt) "->")))
- (setq cmd (read-key-sequence prompt-string))
- (setq last-command-event (aref cmd (1- (length cmd)))
- this-command (key-binding cmd t)
- cmd this-command)
- (if (or (prog1 quit-flag (setq quit-flag nil))
- (eq last-input-event ?\C-g))
- (progn (setq unread-command-events nil
- prefix-arg nil)
- ;; If it wasn't canceling a prefix character, then quit.
- (if (or (= (length (this-command-keys)) 1)
- (not inhibit-quit)) ; safety
- (progn (ding)
- (message "Quit")
- (throw return-tag nil))
- (setq cmd nil))))
- (setq current-prefix-arg prefix-arg)
- (if cmd
- (condition-case conditions
- (progn (command-execute cmd)
- (setq last-command this-command)
- (if (or (prog1 quit-flag (setq quit-flag nil))
- (eq last-input-event ?\C-g))
- (progn (setq unread-command-events nil)
- (if (not inhibit-quit)
- (progn (ding)
- (message "Quit")
- (throw return-tag nil))
- (ding)))))
- (buffer-read-only (if loop-function
- (setq err conditions)
- (ding)
- (message "Buffer is read-only")
- (sit-for 2)))
- (beginning-of-buffer (if loop-function
- (setq err conditions)
- (ding)
- (message "Beginning of Buffer")
- (sit-for 2)))
- (end-of-buffer (if loop-function
- (setq err conditions)
- (ding)
- (message "End of Buffer")
- (sit-for 2)))
- (error (if loop-function
- (setq err conditions)
- (ding)
- (message "Error: %s"
- (if (eq (car conditions) 'error)
- (car (cdr conditions))
- (prin1-to-string conditions)))
- (sit-for 2))))
- (ding))
- (if loop-function (funcall loop-function loop-state err))))
- (ding)
- (throw return-tag nil))
-
-;; This function is like pop-to-buffer, sort of.
-;; The algorithm is
-;; If there is a window displaying buffer
-;; Select it
-;; Else if there is only one window
-;; Split it, selecting the window on the bottom with height being
-;; the lesser of max-height (if non-nil) and the number of lines in
-;; the buffer to be displayed subject to window-min-height constraint.
-;; Else
-;; Switch to buffer in the current window.
-;;
-;; Then if max-height is nil, and not all of the lines in the buffer
-;; are displayed, grab the whole frame.
-;;
-;; Returns selected window on buffer positioned at point-min.
-
-(defun Electric-pop-up-window (buffer &optional max-height)
- (let* ((win (or (get-buffer-window buffer) (selected-window)))
- (buf (get-buffer buffer))
- (one-window (one-window-p t))
- (pop-up-windows t)
- (pop-up-frames nil))
- (if (not buf)
- (error "Buffer %s does not exist" buffer)
- (cond ((and (eq (window-buffer win) buf))
- (select-window win))
- (one-window
- (pop-to-buffer buffer)
- (setq win (selected-window)))
- (t
- (switch-to-buffer buf)))
- ;; Don't shrink the window, but expand it if necessary.
- (goto-char (point-min))
- (unless (= (point-max) (window-end win t))
- (fit-window-to-buffer win max-height))
- win)))
-
-;;; Electric keys.
-
-(defgroup electricity ()
- "Electric behavior for self inserting keys."
- :group 'editing)
-
-(defun electric--after-char-pos ()
- "Return the position after the char we just inserted.
-Returns nil when we can't find this char."
- (let ((pos (point)))
- (when (or (eq (char-before) last-command-event) ;; Sanity check.
- (save-excursion
- (or (progn (skip-chars-backward " \t")
- (setq pos (point))
- (eq (char-before) last-command-event))
- (progn (skip-chars-backward " \n\t")
- (setq pos (point))
- (eq (char-before) last-command-event)))))
- pos)))
-
-(defun electric--sort-post-self-insertion-hook ()
- "Ensure order of electric functions in `post-self-insertion-hook'.
-
-Hooks in this variable interact in non-trivial ways, so a
-relative order must be maintained within it."
- (setq-default post-self-insert-hook
- (sort (default-value 'post-self-insert-hook)
- #'(lambda (fn1 fn2)
- (< (or (get fn1 'priority) 0)
- (or (get fn2 'priority) 0))))))
-
-;;; Electric indentation.
-
-;; Autoloading variables is generally undesirable, but major modes
-;; should usually set this variable by adding elements to the default
-;; value, which only works well if the variable is preloaded.
-;;;###autoload
-(defvar electric-indent-chars '(?\n)
- "Characters that should cause automatic reindentation.")
-
-(defvar electric-indent-functions nil
- "Special hook run to decide whether to auto-indent.
-Each function is called with one argument (the inserted char), with
-point right after that char, and it should return t to cause indentation,
-`no-indent' to prevent indentation or nil to let other functions decide.")
-
-(defvar-local electric-indent-inhibit nil
- "If non-nil, reindentation is not appropriate for this buffer.
-This should be set by major modes such as `python-mode' since
-Python does not lend itself to fully automatic indentation.")
-
-(defvar electric-indent-functions-without-reindent
- '(indent-relative indent-to-left-margin indent-relative-maybe
- py-indent-line coffee-indent-line org-indent-line
- haskell-indentation-indent-line haskell-indent-cycle haskell-simple-indent)
- "List of indent functions that can't reindent.
-If `line-indent-function' is one of those, then `electric-indent-mode' will
-not try to reindent lines. It is normally better to make the major
-mode set `electric-indent-inhibit', but this can be used as a workaround.")
-
-(defun electric-indent-post-self-insert-function ()
- ;; FIXME: This reindents the current line, but what we really want instead is
- ;; to reindent the whole affected text. That's the current line for simple
- ;; cases, but not all cases. We do take care of the newline case in an
- ;; ad-hoc fashion, but there are still missing cases such as the case of
- ;; electric-pair-mode wrapping a region with a pair of parens.
- ;; There might be a way to get it working by analyzing buffer-undo-list, but
- ;; it looks challenging.
- (let (pos)
- (when (and
- electric-indent-mode
- ;; Don't reindent while inserting spaces at beginning of line.
- (or (not (memq last-command-event '(?\s ?\t)))
- (save-excursion (skip-chars-backward " \t") (not (bolp))))
- (setq pos (electric--after-char-pos))
- (save-excursion
- (goto-char pos)
- (let ((act (or (run-hook-with-args-until-success
- 'electric-indent-functions
- last-command-event)
- (memq last-command-event electric-indent-chars))))
- (not
- (or (memq act '(nil no-indent))
- ;; In a string or comment.
- (unless (eq act 'do-indent) (nth 8 (syntax-ppss))))))))
- ;; For newline, we want to reindent both lines and basically behave like
- ;; reindent-then-newline-and-indent (whose code we hence copied).
- (when (<= pos (line-beginning-position))
- (let ((before (copy-marker (1- pos) t)))
- (save-excursion
- (unless (or (memq indent-line-function
- electric-indent-functions-without-reindent)
- electric-indent-inhibit)
- ;; Don't reindent the previous line if the indentation function
- ;; is not a real one.
- (goto-char before)
- (indent-according-to-mode))
- ;; We are at EOL before the call to indent-according-to-mode, and
- ;; after it we usually are as well, but not always. We tried to
- ;; address it with `save-excursion' but that uses a normal marker
- ;; whereas we need `move after insertion', so we do the
- ;; save/restore by hand.
- (goto-char before)
- (when (eolp)
- ;; Remove the trailing whitespace after indentation because
- ;; indentation may (re)introduce the whitespace.
- (delete-horizontal-space t)))))
- (unless (and electric-indent-inhibit
- (> pos (line-beginning-position)))
- (indent-according-to-mode)))))
-
-(put 'electric-indent-post-self-insert-function 'priority 60)
-
-(defun electric-indent-just-newline (arg)
- "Insert just a newline, without any auto-indentation."
- (interactive "*P")
- (let ((electric-indent-mode nil))
- (newline arg 'interactive)))
-
-;;;###autoload
-(define-minor-mode electric-indent-mode
- "Toggle on-the-fly reindentation (Electric Indent mode).
-With a prefix argument ARG, enable Electric Indent mode if ARG is
-positive, and disable it otherwise. If called from Lisp, enable
-the mode if ARG is omitted or nil.
-
-This is a global minor mode. When enabled, it reindents whenever
-the hook `electric-indent-functions' returns non-nil, or you
-insert a character from `electric-indent-chars'."
- :global t :group 'electricity
- :initialize 'custom-initialize-delay
- :init-value t
- (if (not electric-indent-mode)
- (progn
- (when (eq (lookup-key global-map [?\C-j])
- 'electric-indent-just-newline)
- (define-key global-map [?\C-j] 'newline-and-indent))
- (remove-hook 'post-self-insert-hook
- #'electric-indent-post-self-insert-function))
- (when (eq (lookup-key global-map [?\C-j]) 'newline-and-indent)
- (define-key global-map [?\C-j] 'electric-indent-just-newline))
- (add-hook 'post-self-insert-hook
- #'electric-indent-post-self-insert-function)
- (electric--sort-post-self-insertion-hook)))
-
-;;;###autoload
-(define-minor-mode electric-indent-local-mode
- "Toggle `electric-indent-mode' only in this buffer."
- :variable (buffer-local-value 'electric-indent-mode (current-buffer))
- (cond
- ((eq electric-indent-mode (default-value 'electric-indent-mode))
- (kill-local-variable 'electric-indent-mode))
- ((not (default-value 'electric-indent-mode))
- ;; Locally enabled, but globally disabled.
- (electric-indent-mode 1) ; Setup the hooks.
- (setq-default electric-indent-mode nil) ; But keep it globally disabled.
- )))
-
-;;; Electric pairing.
-
-(defcustom electric-pair-pairs
- '((?\" . ?\"))
- "Alist of pairs that should be used regardless of major mode.
-
-Pairs of delimiters in this list are a fallback in case they have
-no syntax relevant to `electric-pair-mode' in the mode's syntax
-table.
-
-See also the variable `electric-pair-text-pairs'."
- :version "24.1"
- :type '(repeat (cons character character)))
-
-(defcustom electric-pair-text-pairs
- '((?\" . ?\" ))
- "Alist of pairs that should always be used in comments and strings.
-
-Pairs of delimiters in this list are a fallback in case they have
-no syntax relevant to `electric-pair-mode' in the syntax table
-defined in `electric-pair-text-syntax-table'"
- :version "24.4"
- :type '(repeat (cons character character)))
-
-(defcustom electric-pair-skip-self #'electric-pair-default-skip-self
- "If non-nil, skip char instead of inserting a second closing paren.
-
-When inserting a closing paren character right before the same character,
-just skip that character instead, so that hitting ( followed by ) results
-in \"()\" rather than \"())\".
-
-This can be convenient for people who find it easier to hit ) than C-f.
-
-Can also be a function of one argument (the closer char just
-inserted), in which case that function's return value is
-considered instead."
- :version "24.1"
- :type '(choice
- (const :tag "Never skip" nil)
- (const :tag "Help balance" electric-pair-default-skip-self)
- (const :tag "Always skip" t)
- function))
-
-(defcustom electric-pair-inhibit-predicate
- #'electric-pair-default-inhibit
- "Predicate to prevent insertion of a matching pair.
-
-The function is called with a single char (the opening char just inserted).
-If it returns non-nil, then `electric-pair-mode' will not insert a matching
-closer."
- :version "24.4"
- :type '(choice
- (const :tag "Conservative" electric-pair-conservative-inhibit)
- (const :tag "Help balance" electric-pair-default-inhibit)
- (const :tag "Always pair" ignore)
- function))
-
-(defcustom electric-pair-preserve-balance t
- "Non-nil if default pairing and skipping should help balance parentheses.
-
-The default values of `electric-pair-inhibit-predicate' and
-`electric-pair-skip-self' check this variable before delegating to other
-predicates reponsible for making decisions on whether to pair/skip some
-characters based on the actual state of the buffer's parenthesis and
-quotes."
- :version "24.4"
- :type 'boolean)
-
-(defcustom electric-pair-delete-adjacent-pairs t
- "If non-nil, backspacing an open paren also deletes adjacent closer.
-
-Can also be a function of no arguments, in which case that function's
-return value is considered instead."
- :version "24.4"
- :type '(choice
- (const :tag "Yes" t)
- (const :tag "No" nil)
- function))
-
-(defcustom electric-pair-open-newline-between-pairs t
- "If non-nil, a newline between adjacent parentheses opens an extra one.
-
-Can also be a function of no arguments, in which case that function's
-return value is considered instead."
- :version "24.4"
- :type '(choice
- (const :tag "Yes" t)
- (const :tag "No" nil)
- function))
-
-(defcustom electric-pair-skip-whitespace t
- "If non-nil skip whitespace when skipping over closing parens.
-
-The specific kind of whitespace skipped is given by the variable
-`electric-pair-skip-whitespace-chars'.
-
-The symbol `chomp' specifies that the skipped-over whitespace
-should be deleted.
-
-Can also be a function of no arguments, in which case that function's
-return value is considered instead."
- :version "24.4"
- :type '(choice
- (const :tag "Yes, jump over whitespace" t)
- (const :tag "Yes, and delete whitespace" 'chomp)
- (const :tag "No, no whitespace skipping" nil)
- function))
-
-(defcustom electric-pair-skip-whitespace-chars (list ?\t ?\s ?\n)
- "Whitespace characters considered by `electric-pair-skip-whitespace'."
- :version "24.4"
- :type '(choice (set (const :tag "Space" ?\s)
- (const :tag "Tab" ?\t)
- (const :tag "Newline" ?\n))
- (list character)))
-
-(defun electric-pair--skip-whitespace ()
- "Skip whitespace forward, not crossing comment or string boundaries."
- (let ((saved (point))
- (string-or-comment (nth 8 (syntax-ppss))))
- (skip-chars-forward (apply #'string electric-pair-skip-whitespace-chars))
- (unless (eq string-or-comment (nth 8 (syntax-ppss)))
- (goto-char saved))))
-
-(defvar electric-pair-text-syntax-table prog-mode-syntax-table
- "Syntax table used when pairing inside comments and strings.
-
-`electric-pair-mode' considers this syntax table only when point in inside
-quotes or comments. If lookup fails here, `electric-pair-text-pairs' will
-be considered.")
-
-(defun electric-pair-backward-delete-char (n &optional killflag untabify)
- "Delete characters backward, and maybe also two adjacent paired delimiters.
-
-Remaining behaviour is given by `backward-delete-char' or, if UNTABIFY is
-non-nil, `backward-delete-char-untabify'."
- (interactive "*p\nP")
- (let* ((prev (char-before))
- (next (char-after))
- (syntax-info (electric-pair-syntax-info prev))
- (syntax (car syntax-info))
- (pair (cadr syntax-info)))
- (when (and (if (functionp electric-pair-delete-adjacent-pairs)
- (funcall electric-pair-delete-adjacent-pairs)
- electric-pair-delete-adjacent-pairs)
- next
- (memq syntax '(?\( ?\" ?\$))
- (eq pair next))
- (delete-char 1 killflag))
- (if untabify
- (backward-delete-char-untabify n killflag)
- (backward-delete-char n killflag))))
-
-(defun electric-pair-backward-delete-char-untabify (n &optional killflag)
- "Delete characters backward, and maybe also two adjacent paired delimiters.
-
-Remaining behaviour is given by `backward-delete-char-untabify'."
- (interactive "*p\nP")
- (electric-pair-backward-delete-char n killflag t))
-
-(defun electric-pair-conservative-inhibit (char)
- (or
- ;; I find it more often preferable not to pair when the
- ;; same char is next.
- (eq char (char-after))
- ;; Don't pair up when we insert the second of "" or of ((.
- (and (eq char (char-before))
- (eq char (char-before (1- (point)))))
- ;; I also find it often preferable not to pair next to a word.
- (eq (char-syntax (following-char)) ?w)))
-
-(defun electric-pair-syntax-info (command-event)
- "Calculate a list (SYNTAX PAIR UNCONDITIONAL STRING-OR-COMMENT-START).
-
-SYNTAX is COMMAND-EVENT's syntax character. PAIR is
-COMMAND-EVENT's pair. UNCONDITIONAL indicates the variables
-`electric-pair-pairs' or `electric-pair-text-pairs' were used to
-lookup syntax. STRING-OR-COMMENT-START indicates that point is
-inside a comment of string."
- (let* ((pre-string-or-comment (nth 8 (save-excursion
- (syntax-ppss (1- (point))))))
- (post-string-or-comment (nth 8 (syntax-ppss (point))))
- (string-or-comment (and post-string-or-comment
- pre-string-or-comment))
- (table (if string-or-comment
- electric-pair-text-syntax-table
- (syntax-table)))
- (table-syntax-and-pair (with-syntax-table table
- (list (char-syntax command-event)
- (or (matching-paren command-event)
- command-event))))
- (fallback (if string-or-comment
- (append electric-pair-text-pairs
- electric-pair-pairs)
- electric-pair-pairs))
- (direct (assq command-event fallback))
- (reverse (rassq command-event fallback)))
- (cond
- ((memq (car table-syntax-and-pair)
- '(?\" ?\( ?\) ?\$))
- (append table-syntax-and-pair (list nil string-or-comment)))
- (direct (if (eq (car direct) (cdr direct))
- (list ?\" command-event t string-or-comment)
- (list ?\( (cdr direct) t string-or-comment)))
- (reverse (list ?\) (car reverse) t string-or-comment)))))
-
-(defun electric-pair--insert (char)
- (let ((last-command-event char)
- (blink-matching-paren nil)
- (electric-pair-mode nil))
- (self-insert-command 1)))
-
-(defun electric-pair--syntax-ppss (&optional pos where)
- "Like `syntax-ppss', but sometimes fallback to `parse-partial-sexp'.
-
-WHERE is list defaulting to '(string comment) and indicates
-when to fallback to `parse-partial-sexp'."
- (let* ((pos (or pos (point)))
- (where (or where '(string comment)))
- (quick-ppss (syntax-ppss))
- (quick-ppss-at-pos (syntax-ppss pos)))
- (if (or (and (nth 3 quick-ppss) (memq 'string where))
- (and (nth 4 quick-ppss) (memq 'comment where)))
- (with-syntax-table electric-pair-text-syntax-table
- (parse-partial-sexp (1+ (nth 8 quick-ppss)) pos))
- ;; HACK! cc-mode apparently has some `syntax-ppss' bugs
- (if (memq major-mode '(c-mode c++ mode))
- (parse-partial-sexp (point-min) pos)
- quick-ppss-at-pos))))
-
-;; Balancing means controlling pairing and skipping of parentheses so
-;; that, if possible, the buffer ends up at least as balanced as
-;; before, if not more. The algorithm is slightly complex because some
-;; situations like "()))" need pairing to occur at the end but not at
-;; the beginning. Balancing should also happen independently for
-;; different types of parentheses, so that having your {}'s unbalanced
-;; doesn't keep `electric-pair-mode' from balancing your ()'s and your
-;; []'s.
-(defun electric-pair--balance-info (direction string-or-comment)
- "Examine lists forward or backward according to DIRECTIONS's sign.
-
-STRING-OR-COMMENT is info suitable for running `parse-partial-sexp'.
-
-Return a cons of two descritions (MATCHED-P . PAIR) for the
-innermost and outermost lists that enclose point. The outermost
-list enclosing point is either the first top-level or first
-mismatched list found by uplisting.
-
-If the outermost list is matched, don't rely on its PAIR. If
-point is not enclosed by any lists, return ((T) (T))."
- (let* (innermost
- outermost
- (table (if string-or-comment
- electric-pair-text-syntax-table
- (syntax-table)))
- (at-top-level-or-equivalent-fn
- ;; called when `scan-sexps' ran perfectly, when when it
- ;; found a parenthesis pointing in the direction of
- ;; travel. Also when travel started inside a comment and
- ;; exited it
- #'(lambda ()
- (setq outermost (list t))
- (unless innermost
- (setq innermost (list t)))))
- (ended-prematurely-fn
- ;; called when `scan-sexps' crashed against a parenthesis
- ;; pointing opposite the direction of travel. After
- ;; traversing that character, the idea is to travel one sexp
- ;; in the opposite direction looking for a matching
- ;; delimiter.
- #'(lambda ()
- (let* ((pos (point))
- (matched
- (save-excursion
- (cond ((< direction 0)
- (condition-case nil
- (eq (char-after pos)
- (with-syntax-table table
- (matching-paren
- (char-before
- (scan-sexps (point) 1)))))
- (scan-error nil)))
- (t
- ;; In this case, no need to use
- ;; `scan-sexps', we can use some
- ;; `electric-pair--syntax-ppss' in this
- ;; case (which uses the quicker
- ;; `syntax-ppss' in some cases)
- (let* ((ppss (electric-pair--syntax-ppss
- (1- (point))))
- (start (car (last (nth 9 ppss))))
- (opener (char-after start)))
- (and start
- (eq (char-before pos)
- (or (with-syntax-table table
- (matching-paren opener))
- opener))))))))
- (actual-pair (if (> direction 0)
- (char-before (point))
- (char-after (point)))))
- (unless innermost
- (setq innermost (cons matched actual-pair)))
- (unless matched
- (setq outermost (cons matched actual-pair)))))))
- (save-excursion
- (while (not outermost)
- (condition-case err
- (with-syntax-table table
- (scan-sexps (point) (if (> direction 0)
- (point-max)
- (- (point-max))))
- (funcall at-top-level-or-equivalent-fn))
- (scan-error
- (cond ((or
- ;; some error happened and it is not of the "ended
- ;; prematurely" kind"...
- (not (string-match "ends prematurely" (nth 1 err)))
- ;; ... or we were in a comment and just came out of
- ;; it.
- (and string-or-comment
- (not (nth 8 (syntax-ppss)))))
- (funcall at-top-level-or-equivalent-fn))
- (t
- ;; exit the sexp
- (goto-char (nth 3 err))
- (funcall ended-prematurely-fn)))))))
- (cons innermost outermost)))
-
-(defun electric-pair--looking-at-unterminated-string-p (char)
- "Say if following string starts with CHAR and is unterminated."
- ;; FIXME: ugly/naive
- (save-excursion
- (skip-chars-forward (format "^%c" char))
- (while (not (zerop (% (save-excursion (skip-syntax-backward "\\")) 2)))
- (unless (eobp)
- (forward-char 1)
- (skip-chars-forward (format "^%c" char))))
- (and (not (eobp))
- (condition-case err
- (progn (forward-sexp) nil)
- (scan-error t)))))
-
-(defun electric-pair--inside-string-p (char)
- "Say if point is inside a string started by CHAR.
-
-A comments text is parsed with `electric-pair-text-syntax-table'.
-Also consider strings within comments, but not strings within
-strings."
- ;; FIXME: could also consider strings within strings by examining
- ;; delimiters.
- (let* ((ppss (electric-pair--syntax-ppss (point) '(comment))))
- (memq (nth 3 ppss) (list t char))))
-
-(defun electric-pair-inhibit-if-helps-balance (char)
- "Return non-nil if auto-pairing of CHAR would hurt parentheses' balance.
-
-Works by first removing the character from the buffer, then doing
-some list calculations, finally restoring the situation as if nothing
-happened."
- (pcase (electric-pair-syntax-info char)
- (`(,syntax ,pair ,_ ,s-or-c)
- (unwind-protect
- (progn
- (delete-char -1)
- (cond ((eq ?\( syntax)
- (let* ((pair-data
- (electric-pair--balance-info 1 s-or-c))
- (innermost (car pair-data))
- (outermost (cdr pair-data)))
- (cond ((car outermost)
- nil)
- (t
- (eq (cdr outermost) pair)))))
- ((eq syntax ?\")
- (electric-pair--looking-at-unterminated-string-p char))))
- (insert-char char)))))
-
-(defun electric-pair-skip-if-helps-balance (char)
- "Return non-nil if skipping CHAR would benefit parentheses' balance.
-
-Works by first removing the character from the buffer, then doing
-some list calculations, finally restoring the situation as if nothing
-happened."
- (pcase (electric-pair-syntax-info char)
- (`(,syntax ,pair ,_ ,s-or-c)
- (unwind-protect
- (progn
- (delete-char -1)
- (cond ((eq syntax ?\))
- (let* ((pair-data
- (electric-pair--balance-info
- -1 s-or-c))
- (innermost (car pair-data))
- (outermost (cdr pair-data)))
- (and
- (cond ((car outermost)
- (car innermost))
- ((car innermost)
- (not (eq (cdr outermost) pair)))))))
- ((eq syntax ?\")
- (electric-pair--inside-string-p char))))
- (insert-char char)))))
-
-(defun electric-pair-default-skip-self (char)
- (if electric-pair-preserve-balance
- (electric-pair-skip-if-helps-balance char)
- t))
-
-(defun electric-pair-default-inhibit (char)
- (if electric-pair-preserve-balance
- (electric-pair-inhibit-if-helps-balance char)
- (electric-pair-conservative-inhibit char)))
-
-(defun electric-pair-post-self-insert-function ()
- (let* ((pos (and electric-pair-mode (electric--after-char-pos)))
- (skip-whitespace-info))
- (pcase (electric-pair-syntax-info last-command-event)
- (`(,syntax ,pair ,unconditional ,_)
- (cond
- ((null pos) nil)
- ;; Wrap a pair around the active region.
- ;;
- ((and (memq syntax '(?\( ?\) ?\" ?\$)) (use-region-p))
- ;; FIXME: To do this right, we'd need a post-self-insert-function
- ;; so we could add-function around it and insert the closer after
- ;; all the rest of the hook has run.
- (if (or (eq syntax ?\")
- (and (eq syntax ?\))
- (>= (point) (mark)))
- (and (not (eq syntax ?\)))
- (>= (mark) (point))))
- (save-excursion
- (goto-char (mark))
- (electric-pair--insert pair))
- (delete-region pos (1- pos))
- (electric-pair--insert pair)
- (goto-char (mark))
- (electric-pair--insert last-command-event)))
- ;; Backslash-escaped: no pairing, no skipping.
- ((save-excursion
- (goto-char (1- pos))
- (not (zerop (% (skip-syntax-backward "\\") 2))))
- nil)
- ;; Skip self.
- ((and (memq syntax '(?\) ?\" ?\$))
- (and (or unconditional
- (if (functionp electric-pair-skip-self)
- (funcall electric-pair-skip-self last-command-event)
- electric-pair-skip-self))
- (save-excursion
- (when (setq skip-whitespace-info
- (if (functionp electric-pair-skip-whitespace)
- (funcall electric-pair-skip-whitespace)
- electric-pair-skip-whitespace))
- (electric-pair--skip-whitespace))
- (eq (char-after) last-command-event))))
- ;; This is too late: rather than insert&delete we'd want to only
- ;; skip (or insert in overwrite mode). The difference is in what
- ;; goes in the undo-log and in the intermediate state which might
- ;; be visible to other post-self-insert-hook. We'll just have to
- ;; live with it for now.
- (when skip-whitespace-info
- (electric-pair--skip-whitespace))
- (delete-region (1- pos) (if (eq skip-whitespace-info 'chomp)
- (point)
- pos))
- (forward-char))
- ;; Insert matching pair.
- ((and (memq syntax `(?\( ?\" ?\$))
- (not overwrite-mode)
- (or unconditional
- (not (funcall electric-pair-inhibit-predicate
- last-command-event))))
- (save-excursion (electric-pair--insert pair)))))
- (t
- (when (and (if (functionp electric-pair-open-newline-between-pairs)
- (funcall electric-pair-open-newline-between-pairs)
- electric-pair-open-newline-between-pairs)
- (eq last-command-event ?\n)
- (not (eobp))
- (eq (save-excursion
- (skip-chars-backward "\t\s")
- (char-before (1- (point))))
- (matching-paren (char-after))))
- (save-excursion (newline 1 t)))))))
-
-(put 'electric-pair-post-self-insert-function 'priority 20)
-
-(defun electric-pair-will-use-region ()
- (and (use-region-p)
- (memq (car (electric-pair-syntax-info last-command-event))
- '(?\( ?\) ?\" ?\$))))
-
-(defvar electric-pair-mode-map
- (let ((map (make-sparse-keymap)))
- (define-key map [remap backward-delete-char-untabify]
- 'electric-pair-backward-delete-char-untabify)
- (define-key map [remap backward-delete-char]
- 'electric-pair-backward-delete-char)
- (define-key map [remap delete-backward-char]
- 'electric-pair-backward-delete-char)
- map)
- "Keymap used by `electric-pair-mode'.")
-
-;;;###autoload
-(define-minor-mode electric-pair-mode
- "Toggle automatic parens pairing (Electric Pair mode).
-With a prefix argument ARG, enable Electric Pair mode if ARG is
-positive, and disable it otherwise. If called from Lisp, enable
-the mode if ARG is omitted or nil.
-
-Electric Pair mode is a global minor mode. When enabled, typing
-an open parenthesis automatically inserts the corresponding
-closing parenthesis. \(Likewise for brackets, etc.)."
- :global t :group 'electricity
- (if electric-pair-mode
- (progn
- (add-hook 'post-self-insert-hook
- #'electric-pair-post-self-insert-function)
- (electric--sort-post-self-insertion-hook)
- (add-hook 'self-insert-uses-region-functions
- #'electric-pair-will-use-region))
- (remove-hook 'post-self-insert-hook
- #'electric-pair-post-self-insert-function)
- (remove-hook 'self-insert-uses-region-functions
- #'electric-pair-will-use-region)))
-
-;;; Electric newlines after/before/around some chars.
-
-(defvar electric-layout-rules nil
- "List of rules saying where to automatically insert newlines.
-
-Each rule has the form (CHAR . WHERE) where CHAR is the char that
-was just inserted and WHERE specifies where to insert newlines
-and can be: nil, `before', `after', `around', `after-stay', or a
-function of no arguments that returns one of those symbols.
-
-The symbols specify where in relation to CHAR the newline
-character(s) should be inserted. `after-stay' means insert a
-newline after CHAR but stay in the same place.")
-
-(defun electric-layout-post-self-insert-function ()
- (let* ((rule (cdr (assq last-command-event electric-layout-rules)))
- pos)
- (when (and rule
- (setq pos (electric--after-char-pos))
- ;; Not in a string or comment.
- (not (nth 8 (save-excursion (syntax-ppss pos)))))
- (let ((end (copy-marker (point)))
- (sym (if (functionp rule) (funcall rule) rule)))
- (set-marker-insertion-type end (not (eq sym 'after-stay)))
- (goto-char pos)
- (pcase sym
- ;; FIXME: we used `newline' down here which called
- ;; self-insert-command and ran post-self-insert-hook recursively.
- ;; It happened to make electric-indent-mode work automatically with
- ;; electric-layout-mode (at the cost of re-indenting lines
- ;; multiple times), but I'm not sure it's what we want.
- ;;
- ;; FIXME: check eolp before inserting \n?
- (`before (goto-char (1- pos)) (skip-chars-backward " \t")
- (unless (bolp) (insert "\n")))
- (`after (insert "\n"))
- (`after-stay (save-excursion
- (let ((electric-layout-rules nil))
- (newline 1 t))))
- (`around (save-excursion
- (goto-char (1- pos)) (skip-chars-backward " \t")
- (unless (bolp) (insert "\n")))
- (insert "\n"))) ; FIXME: check eolp before inserting \n?
- (goto-char end)))))
-
-(put 'electric-layout-post-self-insert-function 'priority 40)
-
-;;;###autoload
-(define-minor-mode electric-layout-mode
- "Automatically insert newlines around some chars.
-With a prefix argument ARG, enable Electric Layout mode if ARG is
-positive, and disable it otherwise. If called from Lisp, enable
-the mode if ARG is omitted or nil.
-The variable `electric-layout-rules' says when and how to insert newlines."
- :global t :group 'electricity
- (cond (electric-layout-mode
- (add-hook 'post-self-insert-hook
- #'electric-layout-post-self-insert-function)
- (electric--sort-post-self-insertion-hook))
- (t
- (remove-hook 'post-self-insert-hook
- #'electric-layout-post-self-insert-function))))
-
-(provide 'electric)
-
-;;; electric.el ends here
+;;; electric.el --- window maker and Command loop for `electric' modes
+
+;; Copyright (C) 1985-1986, 1995, 2001-2014 Free Software Foundation,
+;; Inc.
+
+;; Author: K. Shane Hartman
+;; Maintainer: emacs-devel@gnu.org
+;; 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 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:
+
+;; "Electric" has been used in Emacs to refer to different things.
+;; Among them:
+;;
+;; - electric modes and buffers: modes that typically pop-up in a modal kind of
+;; way a transient buffer that automatically disappears as soon as the user
+;; is done with it.
+;;
+;; - electric keys: self inserting keys which additionally perform some side
+;; operation which happens to be often convenient at that time. Examples of
+;; such side operations are: reindenting code, inserting a newline,
+;; ... auto-fill-mode and abbrev-mode can be considered as built-in forms of
+;; electric key behavior.
+
+;;; Code:
+
+;; This loop is the guts for non-standard modes which retain control
+;; until some event occurs. It is a `do-forever', the only way out is
+;; to throw. It assumes that you have set up the keymap, window, and
+;; everything else: all it does is read commands and execute them -
+;; providing error messages should one occur (if there is no loop
+;; function - which see). The required argument is a tag which should
+;; expect a value of nil if the user decides to punt. The second
+;; argument is the prompt to be used: if nil, use "->", if 'noprompt,
+;; don't use a prompt, if a string, use that string as prompt, and if
+;; a function of no variable, it will be evaluated in every iteration
+;; of the loop and its return value, which can be nil, 'noprompt or a
+;; string, will be used as prompt. Given third argument non-nil, it
+;; INHIBITS quitting unless the user types C-g at toplevel. This is
+;; so user can do things like C-u C-g and not get thrown out. Fourth
+;; argument, if non-nil, should be a function of two arguments which
+;; is called after every command is executed. The fifth argument, if
+;; provided, is the state variable for the function. If the
+;; loop-function gets an error, the loop will abort WITHOUT throwing
+;; (moral: use unwind-protect around call to this function for any
+;; critical stuff). The second argument for the loop function is the
+;; conditions for any error that occurred or nil if none.
+
+(defun Electric-command-loop (return-tag
+ &optional prompt inhibit-quitting
+ loop-function loop-state)
+
+ (let (cmd
+ (err nil)
+ (inhibit-quit inhibit-quitting)
+ (prompt-string prompt))
+ (while t
+ (if (functionp prompt)
+ (setq prompt-string (funcall prompt)))
+ (if (not (stringp prompt-string))
+ (setq prompt-string (unless (eq prompt-string 'noprompt) "->")))
+ (setq cmd (read-key-sequence prompt-string))
+ (setq last-command-event (aref cmd (1- (length cmd)))
+ this-command (key-binding cmd t)
+ cmd this-command)
+ (if (or (prog1 quit-flag (setq quit-flag nil))
+ (eq last-input-event ?\C-g))
+ (progn (setq unread-command-events nil
+ prefix-arg nil)
+ ;; If it wasn't canceling a prefix character, then quit.
+ (if (or (= (length (this-command-keys)) 1)
+ (not inhibit-quit)) ; safety
+ (progn (ding)
+ (message "Quit")
+ (throw return-tag nil))
+ (setq cmd nil))))
+ (setq current-prefix-arg prefix-arg)
+ (if cmd
+ (condition-case conditions
+ (progn (command-execute cmd)
+ (setq last-command this-command)
+ (if (or (prog1 quit-flag (setq quit-flag nil))
+ (eq last-input-event ?\C-g))
+ (progn (setq unread-command-events nil)
+ (if (not inhibit-quit)
+ (progn (ding)
+ (message "Quit")
+ (throw return-tag nil))
+ (ding)))))
+ (buffer-read-only (if loop-function
+ (setq err conditions)
+ (ding)
+ (message "Buffer is read-only")
+ (sit-for 2)))
+ (beginning-of-buffer (if loop-function
+ (setq err conditions)
+ (ding)
+ (message "Beginning of Buffer")
+ (sit-for 2)))
+ (end-of-buffer (if loop-function
+ (setq err conditions)
+ (ding)
+ (message "End of Buffer")
+ (sit-for 2)))
+ (error (if loop-function
+ (setq err conditions)
+ (ding)
+ (message "Error: %s"
+ (if (eq (car conditions) 'error)
+ (car (cdr conditions))
+ (prin1-to-string conditions)))
+ (sit-for 2))))
+ (ding))
+ (if loop-function (funcall loop-function loop-state err))))
+ (ding)
+ (throw return-tag nil))
+
+;; This function is like pop-to-buffer, sort of.
+;; The algorithm is
+;; If there is a window displaying buffer
+;; Select it
+;; Else if there is only one window
+;; Split it, selecting the window on the bottom with height being
+;; the lesser of max-height (if non-nil) and the number of lines in
+;; the buffer to be displayed subject to window-min-height constraint.
+;; Else
+;; Switch to buffer in the current window.
+;;
+;; Then if max-height is nil, and not all of the lines in the buffer
+;; are displayed, grab the whole frame.
+;;
+;; Returns selected window on buffer positioned at point-min.
+
+(defun Electric-pop-up-window (buffer &optional max-height)
+ (let* ((win (or (get-buffer-window buffer) (selected-window)))
+ (buf (get-buffer buffer))
+ (one-window (one-window-p t))
+ (pop-up-windows t)
+ (pop-up-frames nil))
+ (if (not buf)
+ (error "Buffer %s does not exist" buffer)
+ (cond ((and (eq (window-buffer win) buf))
+ (select-window win))
+ (one-window
+ (pop-to-buffer buffer)
+ (setq win (selected-window)))
+ (t
+ (switch-to-buffer buf)))
+ ;; Don't shrink the window, but expand it if necessary.
+ (goto-char (point-min))
+ (unless (= (point-max) (window-end win t))
+ (fit-window-to-buffer win max-height))
+ win)))
+
+;;; Electric keys.
+
+(defgroup electricity ()
+ "Electric behavior for self inserting keys."
+ :group 'editing)
+
+(defun electric--after-char-pos ()
+ "Return the position after the char we just inserted.
+Returns nil when we can't find this char."
+ (let ((pos (point)))
+ (when (or (eq (char-before) last-command-event) ;; Sanity check.
+ (save-excursion
+ (or (progn (skip-chars-backward " \t")
+ (setq pos (point))
+ (eq (char-before) last-command-event))
+ (progn (skip-chars-backward " \n\t")
+ (setq pos (point))
+ (eq (char-before) last-command-event)))))
+ pos)))
+
+(defun electric--sort-post-self-insertion-hook ()
+ "Ensure order of electric functions in `post-self-insertion-hook'.
+
+Hooks in this variable interact in non-trivial ways, so a
+relative order must be maintained within it."
+ (setq-default post-self-insert-hook
+ (sort (default-value 'post-self-insert-hook)
+ #'(lambda (fn1 fn2)
+ (< (or (get fn1 'priority) 0)
+ (or (get fn2 'priority) 0))))))
+
+;;; Electric indentation.
+
+;; Autoloading variables is generally undesirable, but major modes
+;; should usually set this variable by adding elements to the default
+;; value, which only works well if the variable is preloaded.
+;;;###autoload
+(defvar electric-indent-chars '(?\n)
+ "Characters that should cause automatic reindentation.")
+
+(defvar electric-indent-functions nil
+ "Special hook run to decide whether to auto-indent.
+Each function is called with one argument (the inserted char), with
+point right after that char, and it should return t to cause indentation,
+`no-indent' to prevent indentation or nil to let other functions decide.")
+
+(defvar-local electric-indent-inhibit nil
+ "If non-nil, reindentation is not appropriate for this buffer.
+This should be set by major modes such as `python-mode' since
+Python does not lend itself to fully automatic indentation.")
+
+(defvar electric-indent-functions-without-reindent
+ '(indent-relative indent-to-left-margin indent-relative-maybe
+ py-indent-line coffee-indent-line org-indent-line yaml-indent-line
+ haskell-indentation-indent-line haskell-indent-cycle haskell-simple-indent
+ yaml-indent-line)
+ "List of indent functions that can't reindent.
+If `line-indent-function' is one of those, then `electric-indent-mode' will
+not try to reindent lines. It is normally better to make the major
+mode set `electric-indent-inhibit', but this can be used as a workaround.")
+
+(defun electric-indent-post-self-insert-function ()
+ "Function that `electric-indent-mode' adds to `post-self-insert-hook'.
+This indents if the hook `electric-indent-functions' returns non-nil,
+or if a member of `electric-indent-chars' was typed; but not in a string
+or comment."
+ ;; FIXME: This reindents the current line, but what we really want instead is
+ ;; to reindent the whole affected text. That's the current line for simple
+ ;; cases, but not all cases. We do take care of the newline case in an
+ ;; ad-hoc fashion, but there are still missing cases such as the case of
+ ;; electric-pair-mode wrapping a region with a pair of parens.
+ ;; There might be a way to get it working by analyzing buffer-undo-list, but
+ ;; it looks challenging.
+ (let (pos)
+ (when (and
+ electric-indent-mode
+ ;; Don't reindent while inserting spaces at beginning of line.
+ (or (not (memq last-command-event '(?\s ?\t)))
+ (save-excursion (skip-chars-backward " \t") (not (bolp))))
+ (setq pos (electric--after-char-pos))
+ (save-excursion
+ (goto-char pos)
+ (let ((act (or (run-hook-with-args-until-success
+ 'electric-indent-functions
+ last-command-event)
+ (memq last-command-event electric-indent-chars))))
+ (not
+ (or (memq act '(nil no-indent))
+ ;; In a string or comment.
+ (unless (eq act 'do-indent) (nth 8 (syntax-ppss))))))))
+ ;; For newline, we want to reindent both lines and basically behave like
+ ;; reindent-then-newline-and-indent (whose code we hence copied).
+ (let ((at-newline (<= pos (line-beginning-position))))
+ (when at-newline
+ (let ((before (copy-marker (1- pos) t)))
+ (save-excursion
+ (unless (or (memq indent-line-function
+ electric-indent-functions-without-reindent)
+ electric-indent-inhibit)
+ ;; Don't reindent the previous line if the indentation function
+ ;; is not a real one.
+ (goto-char before)
+ (indent-according-to-mode))
+ ;; We are at EOL before the call to indent-according-to-mode, and
+ ;; after it we usually are as well, but not always. We tried to
+ ;; address it with `save-excursion' but that uses a normal marker
+ ;; whereas we need `move after insertion', so we do the
+ ;; save/restore by hand.
+ (goto-char before)
+ (when (eolp)
+ ;; Remove the trailing whitespace after indentation because
+ ;; indentation may (re)introduce the whitespace.
+ (delete-horizontal-space t)))))
+ (unless (and electric-indent-inhibit
+ (not at-newline))
+ (indent-according-to-mode))))))
+
+(put 'electric-indent-post-self-insert-function 'priority 60)
+
+(defun electric-indent-just-newline (arg)
+ "Insert just a newline, without any auto-indentation."
+ (interactive "*P")
+ (let ((electric-indent-mode nil))
+ (newline arg 'interactive)))
+
+;;;###autoload
+(define-key global-map "\C-j" 'electric-newline-and-maybe-indent)
+;;;###autoload
+(defun electric-newline-and-maybe-indent ()
+ "Insert a newline.
+If `electric-indent-mode' is enabled, that's that, but if it
+is *disabled* then additionally indent according to major mode.
+Indentation is done using the value of `indent-line-function'.
+In programming language modes, this is the same as TAB.
+In some text modes, where TAB inserts a tab, this command indents to the
+column specified by the function `current-left-margin'."
+ (interactive "*")
+ (if electric-indent-mode
+ (electric-indent-just-newline nil)
+ (newline-and-indent)))
+
+;;;###autoload
+(define-minor-mode electric-indent-mode
+ "Toggle on-the-fly reindentation (Electric Indent mode).
+With a prefix argument ARG, enable Electric Indent mode if ARG is
+positive, and disable it otherwise. If called from Lisp, enable
+the mode if ARG is omitted or nil.
+
+When enabled, this reindents whenever the hook `electric-indent-functions'
+returns non-nil, or if you insert a character from `electric-indent-chars'.
+
+This is a global minor mode. To toggle the mode in a single buffer,
+use `electric-indent-local-mode'."
+ :global t :group 'electricity
+ :initialize 'custom-initialize-delay
+ :init-value t
+ (if (not electric-indent-mode)
+ (unless (catch 'found
+ (dolist (buf (buffer-list))
+ (with-current-buffer buf
+ (if electric-indent-mode (throw 'found t)))))
+ (remove-hook 'post-self-insert-hook
+ #'electric-indent-post-self-insert-function))
+ (add-hook 'post-self-insert-hook
+ #'electric-indent-post-self-insert-function)
+ (electric--sort-post-self-insertion-hook)))
+
+;;;###autoload
+(define-minor-mode electric-indent-local-mode
+ "Toggle `electric-indent-mode' only in this buffer."
+ :variable (buffer-local-value 'electric-indent-mode (current-buffer))
+ (cond
+ ((eq electric-indent-mode (default-value 'electric-indent-mode))
+ (kill-local-variable 'electric-indent-mode))
+ ((not (default-value 'electric-indent-mode))
+ ;; Locally enabled, but globally disabled.
+ (electric-indent-mode 1) ; Setup the hooks.
+ (setq-default electric-indent-mode nil) ; But keep it globally disabled.
+ )))
+
+;;; Electric newlines after/before/around some chars.
+
+(defvar electric-layout-rules nil
+ "List of rules saying where to automatically insert newlines.
+
+Each rule has the form (CHAR . WHERE) where CHAR is the char that
+was just inserted and WHERE specifies where to insert newlines
+and can be: nil, `before', `after', `around', `after-stay', or a
+function of no arguments that returns one of those symbols.
+
+The symbols specify where in relation to CHAR the newline
+character(s) should be inserted. `after-stay' means insert a
+newline after CHAR but stay in the same place.")
+
+(defun electric-layout-post-self-insert-function ()
+ (let* ((rule (cdr (assq last-command-event electric-layout-rules)))
+ pos)
+ (when (and rule
+ (setq pos (electric--after-char-pos))
+ ;; Not in a string or comment.
+ (not (nth 8 (save-excursion (syntax-ppss pos)))))
+ (let ((end (point-marker))
+ (sym (if (functionp rule) (funcall rule) rule)))
+ (set-marker-insertion-type end (not (eq sym 'after-stay)))
+ (goto-char pos)
+ (pcase sym
+ ;; FIXME: we used `newline' down here which called
+ ;; self-insert-command and ran post-self-insert-hook recursively.
+ ;; It happened to make electric-indent-mode work automatically with
+ ;; electric-layout-mode (at the cost of re-indenting lines
+ ;; multiple times), but I'm not sure it's what we want.
+ ;;
+ ;; FIXME: check eolp before inserting \n?
+ (`before (goto-char (1- pos)) (skip-chars-backward " \t")
+ (unless (bolp) (insert "\n")))
+ (`after (insert "\n"))
+ (`after-stay (save-excursion
+ (let ((electric-layout-rules nil))
+ (newline 1 t))))
+ (`around (save-excursion
+ (goto-char (1- pos)) (skip-chars-backward " \t")
+ (unless (bolp) (insert "\n")))
+ (insert "\n"))) ; FIXME: check eolp before inserting \n?
+ (goto-char end)))))
+
+(put 'electric-layout-post-self-insert-function 'priority 40)
+
+;;;###autoload
+(define-minor-mode electric-layout-mode
+ "Automatically insert newlines around some chars.
+With a prefix argument ARG, enable Electric Layout mode if ARG is
+positive, and disable it otherwise. If called from Lisp, enable
+the mode if ARG is omitted or nil.
+The variable `electric-layout-rules' says when and how to insert newlines."
+ :global t :group 'electricity
+ (cond (electric-layout-mode
+ (add-hook 'post-self-insert-hook
+ #'electric-layout-post-self-insert-function)
+ (electric--sort-post-self-insertion-hook))
+ (t
+ (remove-hook 'post-self-insert-hook
+ #'electric-layout-post-self-insert-function))))
+
+(provide 'electric)
+
+;;; electric.el ends here
HCoop / bpt / emacs.git / blobdiff