------------------------------------------------------------
revno: 282
committer: Stefan Monnier <monn...@iro.umontreal.ca>
branch nick: elpa
timestamp: Wed 2012-10-24 15:29:40 -0400
message:
* nlinum.el: Speed up by caching last line-number.
(nlinum--line-number-cache): New var.
(nlinum--after-change, nlinum--line-number-at-pos): New functions.
(nlinum-mode, nlinum--region): Use them.
modified:
packages/nlinum/nlinum.el
=== modified file 'packages/nlinum/nlinum.el'
--- a/packages/nlinum/nlinum.el 2012-06-08 19:15:39 +0000
+++ b/packages/nlinum/nlinum.el 2012-10-24 19:29:40 +0000
@@ -4,7 +4,7 @@
;; Author: Stefan Monnier <monn...@iro.umontreal.ca>
;; Keywords: convenience
-;; Version: 1.0
+;; Version: 1.1
;; This program is free software; you can redistribute it and/or modify
;; it under the terms of the GNU General Public License as published by
@@ -44,11 +44,14 @@
:lighter nil ;; (" NLinum" nlinum--desc)
(jit-lock-unregister #'nlinum--region)
(remove-hook 'window-configuration-change-hook #'nlinum--setup-window t)
+ (remove-hook 'after-change-functions #'nlinum--after-change)
+ (kill-local-variable 'nlinum--line-number-cache)
(remove-overlays (point-min) (point-max) 'nlinum t)
;; (kill-local-variable 'nlinum--ol-counter)
(kill-local-variable 'nlinum--width)
(when nlinum-mode
(add-hook 'window-configuration-change-hook #'nlinum--setup-window nil t)
+ (add-hook 'after-change-functions #'nlinum--after-change nil t)
(jit-lock-register #'nlinum--region t))
(nlinum--setup-windows))
@@ -118,6 +121,28 @@
;; (- debug-count debug-new-count) debug-new-count)))))
+(defvar nlinum--line-number-cache nil)
+(make-variable-buffer-local 'nlinum--line-number-cache)
+
+(defun nlinum--after-change (&rest _args)
+ (setq nlinum--line-number-cache nil))
+
+(defun nlinum--line-number-at-pos ()
+ "Like `line-number-at-pos' but sped up with a cache."
+ ;; (assert (bolp))
+ (let ((pos
+ (if (and nlinum--line-number-cache
+ (> (- (point) (point-min))
+ (abs (- (point) (car nlinum--line-number-cache)))))
+ (funcall (if (> (point) (car nlinum--line-number-cache))
+ #'+ #'-)
+ (cdr nlinum--line-number-cache)
+ (count-lines (point) (car nlinum--line-number-cache)))
+ (line-number-at-pos))))
+ ;;(assert (= pos (line-number-at-pos)))
+ (setq nlinum--line-number-cache (cons (point) pos))
+ pos))
+
(defun nlinum--region (start limit)
(save-excursion
;; Text may contain those nasty intangible properties, but
@@ -126,7 +151,7 @@
(goto-char start)
(unless (bolp) (forward-line 1))
(remove-overlays (point) limit 'nlinum t)
- (let ((line (line-number-at-pos))
+ (let ((line (nlinum--line-number-at-pos))
(fmt (format "%%%dd" nlinum--width)))
(while
(and (not (eobp)) (< (point) limit)
