Summary: ;;; linum-ex.el --- Display line numbers to the left of buffers ;; originally derived from linum.el, which is ;; Copyright (C) 2007, 2008 Markus . . .No diff available.
;;; linum-ex.el --- Display line numbers to the left of buffers ;; originally derived from linum.el, which is ;; Copyright (C) 2007, 2008 Markus Triska ;; modifications in linum-ex.el provided by: Dino Chiesa ;; Author: Markus Triska <email@example.com> ;; Last saved: <2011-May-23 12:47:18> ;; ;; Keywords: convenience ;; This file 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, or (at your option) ;; any later version. ;; This file 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., 51 Franklin Street, Fifth Floor, ;; Boston, MA 02110-1301, USA. ;;; Commentary: ;; Display line numbers for the current buffer. Copy linum-ex.el to your ;; load-path and add to your .emacs: ;; (require 'linum-ex) ;; Then toggle display of line numbers with M-x linum-mode. To enable ;; line numbering in all buffers, use M-x global-linum-mode. ;; ======================================================= ;; ;; Dino Chiesa Mon, 23 May 2011 12:00 ;; ;; notes on changes. ;; ;; The problem with the original linum module is that it updated the ;; line numbers after every scroll and possibly every command. This ;; works for small files but not for files with 100,000+ lines. Even ;; with linum-delay turned on, linum had the effect of "Freezing" the ;; display when the user was continuously scrolling. It also introduced ;; noticeable delays when scrolling only momentarily. ;; ;; One idea for working around that is to use run-with-idle-timer, and ;; only update the line numbers when emacs is idle. One can set a single ;; timer, for, say 0.1s, and then when emacs goes idle for that period, ;; the line numbers will be updated. Seems like the perfect fit, ;; but there's a problem: a timer created via run-with-idle-timer ;; gets canceled after being delayed 10 times. ;; ;; So if the after-scroll event sets up a timer via run-with-idle-timer, ;; only when no timer has been set, the timer may get canceled silently, ;; by timer.el . Look at `timer-max-repeats'. ;; ;; This happens if emacs is busy for 1s, as for example when the user is ;; holding pgdn to continuously scroll through a large document. If the ;; timer doesn't fire, then the line numbers don't ever get updated. ;; ;; To avoid that pitfall, this code can set run-with-idle-timer for ;; every scroll event, and handle the delay explicitly, right here. The ;; way to do it is, within the after-scroll event, store the "last ;; scrolled" time, and then call `run-with-idle-timer'. There may be ;; other outstanding timer events, but we don't care. In the function ;; that gets called when the timer fires, check to see if a reasonable ;; interval (Say 0.1s) has elapsed since the last scroll event. If so, ;; do linum-update. If not, it means scrolling is still happening, so, ;; do nothing. All this applies only if linum-delay is non-nil. ;; ;; The result is that timers fire constantly while the user is ;; continuously scrolling, but the line numbers get updated only after ;; the user stops scrolling. The user experiences no delay while ;; scrolling, but (unfortunately) gets no line numbers either. The user ;; sees updated line numbers immediately when he stops. ;; ;; ======================================================= ;;; Code: (require 'timer) (defconst linum-version "0.991") (defvar linum-overlays nil "Overlays used in this buffer.") (defvar linum-available nil "Overlays available for reuse.") (defvar linum-before-numbering-hook nil "Functions run in each buffer before line numbering starts.") (mapc #'make-variable-buffer-local '(linum-overlays linum-available)) (defgroup linum nil "Show line numbers to the left of buffers" :group 'convenience) ;;;###autoload (defcustom linum-format 'dynamic "Format used to display line numbers. Either a format string like \"%7d\", 'dynamic to adapt the width as needed, or a function that is called with a line number as its argument and should evaluate to a string to be shown on that line. See also `linum-before-numbering-hook'." :group 'linum :type 'sexp) (defface linum '((t :inherit (shadow default))) "Face for displaying line numbers in the display margin." :group 'linum) (defcustom linum-eager t "Whether line numbers should be updated after each command. The conservative setting `nil' might miss some buffer changes, and you have to scroll or press C-l to update the numbers." :group 'linum :type 'boolean) (defcustom linum-delay nil "Delay updates to give Emacs a chance for other changes." :group 'linum :type 'boolean) (defvar linum--delay-time 0.1 "Delay time. See also `linum-delay'") (defvar linum--last-scroll nil "Time of last scroll event. See also `linum-delay'") (defvar linum--last-cmd nil "Time of last command. See also `linum-delay'") (defvar linum--win nil "Window of the last scroll event. See also `linum-delay'") ;;;###autoload (define-minor-mode linum-mode "Toggle display of line numbers in the left marginal area." :lighter "" ; for desktop.el (if linum-mode (progn (if linum-eager (add-hook 'post-command-hook 'linum-post-command) (add-hook 'after-change-functions 'linum-after-change nil t)) (add-hook 'window-scroll-functions 'linum-after-scroll nil t) ;; mistake in Emacs: window-size-change-functions cannot be local (add-hook 'window-size-change-functions 'linum-after-size) (add-hook 'change-major-mode-hook 'linum-delete-overlays nil t) (add-hook 'window-configuration-change-hook 'linum-after-config nil t) (set (make-local-variable 'linum--win) nil) (set (make-local-variable 'linum--last-scroll) nil) (set (make-local-variable 'linum--last-cmd) nil) (linum-update-current)) (remove-hook 'post-command-hook 'linum-post-command t) (remove-hook 'window-size-change-functions 'linum-after-size) (remove-hook 'window-scroll-functions 'linum-after-scroll t) (remove-hook 'after-change-functions 'linum-after-change t) (remove-hook 'window-configuration-change-hook 'linum-after-config t) (remove-hook 'change-major-mode-hook 'linum-delete-overlays t) (linum-delete-overlays))) ;;;###autoload (define-globalized-minor-mode global-linum-mode linum-mode linum-on) (defun linum-on () (unless (minibufferp) (linum-mode 1))) (defun linum-delete-overlays () "Delete all overlays displaying line numbers for this buffer." (mapc #'delete-overlay linum-overlays) (setq linum-overlays nil) (dolist (w (get-buffer-window-list (current-buffer) nil t)) (set-window-margins w 0))) (defun linum-update-current () "Update line numbers for the current buffer." (linum-update (current-buffer))) (defun linum-update (buffer) "Update line numbers for all windows displaying BUFFER." (with-current-buffer buffer (when linum-mode (setq linum-available linum-overlays) (setq linum-overlays nil) (save-excursion (mapc #'linum-update-window (get-buffer-window-list buffer nil 'visible))) (mapc #'delete-overlay linum-available) (setq linum-available nil linum--last-cmd nil linum--last-scroll nil)))) (defun linum-update-window (win) "Update line numbers for the portion visible in window WIN." (goto-char (window-start win)) (let ((line (line-number-at-pos)) (limit (window-end win t)) (fmt (cond ((stringp linum-format) linum-format) ((eq linum-format 'dynamic) (let ((w (length (number-to-string (count-lines (point-min) (point-max)))))) (concat "%" (number-to-string w) "d"))))) (width 0)) (run-hooks 'linum-before-numbering-hook) ;; Create an overlay (or reuse an existing one) for each ;; line visible in this window, if necessary. (while (and (not (eobp)) (<= (point) limit)) (let* ((str (if fmt (propertize (format fmt line) 'face 'linum) (funcall linum-format line))) (visited (catch 'visited (dolist (o (overlays-in (point) (point))) (when (string= (overlay-get o 'linum-str) str) (unless (memq o linum-overlays) (push o linum-overlays)) (setq linum-available (delete o linum-available)) (throw 'visited t)))))) (setq width (max width (length str))) (unless visited (let ((ov (if (null linum-available) (make-overlay (point) (point)) (move-overlay (pop linum-available) (point) (point))))) (push ov linum-overlays) (overlay-put ov 'before-string (propertize " " 'display `((margin left-margin) ,str))) (overlay-put ov 'linum-str str)))) (forward-line) (setq line (1+ line))) (set-window-margins win width))) (defun linum-after-change (beg end len) ;; update overlays on deletions, and after newlines are inserted (when (or (= beg end) (= end (point-max)) ;; TODO: use string-match-p with CVS or new release (string-match "\n" (buffer-substring-no-properties beg end))) (linum-update-current))) (defun linum--after-scroll-fired () (if linum--last-scroll (let ((now (current-time)) (one-moment-after-scroll (timer-relative-time linum--last-scroll linum--delay-time))) (if (time-less-p one-moment-after-scroll now) (linum-update linum--win))))) (defun linum-after-scroll (win start) (if linum-delay (progn (setq linum--win (window-buffer win)) (setq linum--last-scroll (current-time)) (run-with-idle-timer linum--delay-time nil 'linum--after-scroll-fired)) (linum-update (window-buffer win)))) (defun linum--post-command-fired () (if linum--last-cmd (let ((now (current-time)) (one-moment-after-cmd (timer-relative-time linum--last-cmd linum--delay-time))) (if (time-less-p one-moment-after-cmd now) (linum-update-current))))) (defun linum-post-command () (if linum-delay (progn (setq linum--win (window-buffer win)) (setq linum--last-cmd (current-time)) (run-with-idle-timer linum--delay-time nil 'linum--post-command-fired)) (linum-update-current))) (defun linum-after-size (frame) (linum-after-config)) (defun linum-after-config () (walk-windows (lambda (w) (linum-update (window-buffer w))) nil 'visible)) (provide 'linum-ex) ;;; linum-ex.el ends here