mirror of
https://git.savannah.gnu.org/git/emacs.git
synced 2024-12-23 10:34:07 +00:00
166 lines
6.0 KiB
EmacsLisp
166 lines
6.0 KiB
EmacsLisp
;;; electric.el --- window maker and Command loop for `electric' modes
|
|
|
|
;; Copyright (C) 1985, 1986, 1995, 2001, 2002, 2003, 2004,
|
|
;; 2005, 2006, 2007, 2008, 2009 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:
|
|
|
|
; zaaaaaaap
|
|
|
|
;;; 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-quit
|
|
loop-function loop-state)
|
|
|
|
(let (cmd
|
|
(err nil)
|
|
(prompt-string prompt))
|
|
(while t
|
|
(if (not (or (stringp prompt) (eq prompt nil) (eq prompt 'noprompt)))
|
|
(setq prompt-string (funcall prompt)))
|
|
(if (not (stringp prompt-string))
|
|
(if (eq prompt-string 'noprompt)
|
|
(setq prompt-string nil)
|
|
(setq prompt-string "->")))
|
|
(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)
|
|
;; This makes universal-argument-other-key work.
|
|
(setq universal-argument-num-events 0)
|
|
(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 cancelling 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)))
|
|
|
|
(provide 'electric)
|
|
|
|
;; arch-tag: dae045eb-dc2d-4fb7-9f27-9cc2ce277be8
|
|
;;; electric.el ends here
|