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Diffstat (limited to 'lisp/reposition.el')
-rw-r--r-- | lisp/reposition.el | 197 |
1 files changed, 0 insertions, 197 deletions
diff --git a/lisp/reposition.el b/lisp/reposition.el deleted file mode 100644 index f7285c80826..00000000000 --- a/lisp/reposition.el +++ /dev/null @@ -1,197 +0,0 @@ -;;; reposition.el --- center a Lisp function or comment on the screen - -;; Copyright (C) 1991 Free Software Foundation, Inc. - -;; Author: Michael D. Ernst <mernst@theory.lcs.mit.edu> -;; Created: Jan 1991 -;; Maintainer: FSF - -;; 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: - -;;; Reposition-window makes an entire function definition or comment visible, -;;; or, if it is already visible, places it at the top of the window; -;;; additional invocations toggle the visibility of comments preceding the -;;; code. For the gory details, see the documentation for reposition-window; -;;; rather than reading that, you may just want to play with it. - -;;; This tries pretty hard to do the recentering correctly; the precise -;;; action depends on what the buffer looks like. If you find a situation -;;; where it doesn't behave well, let me know. This function is modeled -;;; after one of the same name in ZMACS, but the code is all-new and the -;;; behavior in some situations differs. - -;;; Code: - -;;;###autoload -(defun reposition-window (&optional arg) - "Make the current definition and/or comment visible. -Further invocations move it to the top of the window or toggle the -visibility of comments that precede it. - Point is left unchanged unless prefix ARG is supplied. - If the definition is fully onscreen, it is moved to the top of the -window. If it is partly offscreen, the window is scrolled to get the -definition (or as much as will fit) onscreen, unless point is in a comment -which is also partly offscreen, in which case the scrolling attempts to get -as much of the comment onscreen as possible. - Initially `reposition-window' attempts to make both the definition and -preceding comments visible. Further invocations toggle the visibility of -the comment lines. - If ARG is non-nil, point may move in order to make the whole defun -visible (if only part could otherwise be made so), to make the defun line -visible (if point is in code and it could not be made so, or if only -comments, including the first comment line, are visible), or to make the -first comment line visible (if point is in a comment)." - (interactive "P") - (let* (;; (here (save-excursion (beginning-of-line) (point))) - (here (point)) - ;; change this name once I've gotten rid of references to ht. - ;; this is actually the number of the last screen line - (ht (- (window-height (selected-window)) 2)) - (line (repos-count-screen-lines (window-start) (point))) - (comment-height - ;; The call to max deals with the case of cursor between defuns. - (max 0 - (repos-count-screen-lines-signed - ;; the beginning of the preceding comment - (save-excursion - (if (not (eobp)) (forward-char 1)) - (end-of-defun -1) - ;; Skip whitespace, newlines, and form feeds. - (if (re-search-forward "[^ \t\n\f]" nil t) - (backward-char 1)) - (point)) - here))) - (defun-height - (repos-count-screen-lines-signed - (save-excursion - (end-of-defun 1) ; so comments associate with following defuns - (beginning-of-defun 1) - (point)) - here)) - ;; This must be positive, so don't use the signed version. - (defun-depth (repos-count-screen-lines here - (save-excursion - (end-of-defun 1) - (point)))) - (defun-line-onscreen-p - (and (<= defun-height line) - (<= (- line defun-height) ht)))) - (cond ((or (= comment-height line) - (and (= line ht) - (> comment-height line) - ;; if defun line offscreen, we should be in case 4 - defun-line-onscreen-p)) - ;; Either first comment line is at top of screen or (point at - ;; bottom of screen, defun line onscreen, and first comment line - ;; off top of screen). That is, it looks like we just did - ;; recenter-definition, trying to fit as much of the comment - ;; onscreen as possible. Put defun line at top of screen; that - ;; is, show as much code, and as few comments, as possible. - - (if (and arg (> defun-depth (1+ ht))) - ;; Can't fit whole defun onscreen without moving point. - (progn (end-of-defun) (beginning-of-defun) (recenter 0)) - (recenter (max defun-height 0))) - ;;(repos-debug-macro "1") - ) - - ((or (= defun-height line) - (= line 0) - (and (< line comment-height) - (< defun-height 0))) - ;; Defun line or cursor at top of screen, OR cursor in comment - ;; whose first line is offscreen. - ;; Avoid moving definition up even if defun runs offscreen; - ;; we care more about getting the comment onscreen. - - (cond ((= line ht) - ;; cursor on last screen line (and so in a comment) - (if arg (progn (end-of-defun) (beginning-of-defun))) - (recenter 0) - ;;(repos-debug-macro "2a") - ) - - ;; This condition, copied from case 4, may not be quite right - - ((and arg (< ht comment-height)) - ;; Can't get first comment line onscreen. - ;; Go there and try again. - (forward-line (- comment-height)) - (beginning-of-line) - ;; was (reposition-window) - (recenter 0) - ;;(repos-debug-macro "2b") - ) - (t - (recenter (min ht comment-height)) - ;;(repos-debug-macro "2c") - )) - ;; (recenter (min ht comment-height)) - ) - - ((and (> (+ line defun-depth -1) ht) - defun-line-onscreen-p) - ;; Defun runs off the bottom of the screen and the defun line - ;; is onscreen. - ;; Move the defun up. - (recenter (max 0 (1+ (- ht defun-depth)) defun-height)) - ;;(repos-debug-macro "3") - ) - - (t - ;; If on the bottom line and comment start is offscreen - ;; then just move all comments offscreen, or at least as - ;; far as they'll go. - - ;; Try to get as much of the comments onscreen as possible. - (if (and arg (< ht comment-height)) - ;; Can't get defun line onscreen; go there and try again. - (progn (forward-line (- defun-height)) - (beginning-of-line) - (reposition-window)) - (recenter (min ht comment-height))) - ;;(repos-debug-macro "4") - )))) - -;;;###autoload (define-key esc-map "\C-l" 'reposition-window) - -;;; Auxiliary functions - -;; Return number of screen lines between START and END. -(defun repos-count-screen-lines (start end) - (save-excursion - (save-restriction - (narrow-to-region start end) - (goto-char (point-min)) - (vertical-motion (- (point-max) (point-min)))))) - -;; Return number of screen lines between START and END; returns a negative -;; number if END precedes START. -(defun repos-count-screen-lines-signed (start end) - (let ((lines (repos-count-screen-lines start end))) - (if (< start end) - lines - (- lines)))) - -; (defmacro repos-debug-macro (case-no) -; (` (message -; (concat "Case " (, case-no) ": %s %s %s %s %s") -; ht line comment-height defun-height defun-depth))) - -;;; reposition.el ends here |