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diff --git a/lisp/obsolete/lazy-lock.el b/lisp/obsolete/lazy-lock.el deleted file mode 100644 index 5c35cb32124..00000000000 --- a/lisp/obsolete/lazy-lock.el +++ /dev/null @@ -1,1025 +0,0 @@ -;;; lazy-lock.el --- lazy demand-driven fontification for fast Font Lock mode -*- lexical-binding: t; -*- - -;; Copyright (C) 1994-1998, 2001-2022 Free Software Foundation, Inc. - -;; Author: Simon Marshall <simon@gnu.org> -;; Maintainer: emacs-devel@gnu.org -;; Keywords: faces files -;; Version: 2.11 -;; Obsolete-since: 22.1 - -;; 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 <https://www.gnu.org/licenses/>. - -;;; Commentary: - -;; Purpose: -;; -;; Lazy Lock mode is a Font Lock support mode. -;; It makes visiting buffers in Font Lock mode faster by making fontification -;; be demand-driven, deferred and stealthy, so that fontification only occurs -;; when, and where, necessary. -;; -;; See caveats and feedback below. -;; See also the fast-lock package. (But don't use them at the same time!) - -;; Installation: -;; -;; Put in your ~/.emacs: -;; -;; (setq font-lock-support-mode 'lazy-lock-mode) -;; -;; Start up a new Emacs and use font-lock as usual (except that you can use the -;; so-called "gaudier" fontification regexps on big files without frustration). -;; -;; In a buffer (which has `font-lock-mode' enabled) which is at least -;; `lazy-lock-minimum-size' characters long, buffer fontification will not -;; occur and only the visible portion of the buffer will be fontified. Motion -;; around the buffer will fontify those visible portions not previously -;; fontified. If stealth fontification is enabled, buffer fontification will -;; occur in invisible parts of the buffer after `lazy-lock-stealth-time' -;; seconds of idle time. If on-the-fly fontification is deferred, on-the-fly -;; fontification will occur after `lazy-lock-defer-time' seconds of idle time. - -;; User-visible differences with version 1: -;; -;; - Version 2 can defer on-the-fly fontification. Therefore you need not, and -;; should not, use defer-lock.el with this version of lazy-lock.el. -;; -;; A number of variables have changed meaning: -;; -;; - A value of nil for the variable `lazy-lock-minimum-size' means never turn -;; on demand-driven fontification. In version 1 this meant always turn on -;; demand-driven fontification. If you really want demand-driven fontification -;; regardless of buffer size, set this variable to 0. -;; -;; - The variable `lazy-lock-stealth-lines' cannot have a nil value. In -;; version 1 this meant use `window-height' as the maximum number of lines to -;; fontify as a stealth chunk. This makes no sense; stealth fontification is -;; of a buffer, not a window. - -;; Implementation differences with version 1: -;; -;; - Version 1 of lazy-lock.el is a bit of a hack. Version 1 demand-driven -;; fontification, the core feature of lazy-lock.el, is implemented by placing a -;; function on `post-command-hook'. This function fontifies where necessary, -;; i.e., where a window scroll has occurred. However, there are a number of -;; problems with using `post-command-hook': -;; -;; (a) As the name suggests, `post-command-hook' is run after every command, -;; i.e., frequently and regardless of whether scrolling has occurred. -;; (b) Scrolling can occur during a command, when `post-command-hook' is not -;; run, i.e., it is not necessarily run after scrolling has occurred. -;; (c) When `post-command-hook' is run, there is nothing to suggest where -;; scrolling might have occurred, i.e., which windows have scrolled. -;; -;; Thus lazy-lock.el's function is called almost as often as possible, usually -;; when it need not be called, yet it is not always called when it is needed. -;; Also, lazy-lock.el's function must check each window to see if a scroll has -;; occurred there. Worse still, lazy-lock.el's function must fontify a region -;; twice as large as necessary to make sure the window is completely fontified. -;; Basically, `post-command-hook' is completely inappropriate for lazy-lock.el. -;; -;; Ideally, we want to attach lazy-lock.el's function to a hook that is run -;; only when scrolling occurs, e.g., `window-start' has changed, and tells us -;; as much information as we need, i.e., the window and its new buffer region. -;; Richard Stallman implemented a `window-scroll-functions' for Emacs 19.30. -;; Functions on it are run when `window-start' has changed, and are supplied -;; with the window and the window's new `window-start' position. (It would be -;; better if it also supplied the window's new `window-end' position, but that -;; is calculated as part of the redisplay process, and the functions on -;; `window-scroll-functions' are run before redisplay has finished.) Thus, the -;; hook deals with the above problems (a), (b) and (c). -;; -;; If only life was that easy. Version 2 demand-driven fontification is mostly -;; implemented by placing a function on `window-scroll-functions'. However, -;; not all scrolling occurs when `window-start' has changed. A change in -;; window size, e.g., via C-x 1, or a significant deletion, e.g., of a number -;; of lines, causes text previously invisible (i.e., after `window-end') to -;; become visible without changing `window-start'. Arguably, these events are -;; not scrolling events, but fontification must occur for lazy-lock.el to work. -;; Hooks `window-size-change-functions' and `redisplay-end-trigger-functions' -;; were added for these circumstances. -;; -;; (Ben Wing thinks these hooks are "horribly horribly kludgy", and implemented -;; a `pre-idle-hook', a `mother-of-all-post-command-hooks', for XEmacs 19.14. -;; He then hacked up a version 1 lazy-lock.el to use `pre-idle-hook' rather -;; than `post-command-hook'. Whereas functions on `post-command-hook' are -;; called almost as often as possible, functions on `pre-idle-hook' really are -;; called as often as possible, even when the mouse moves and, on some systems, -;; while XEmacs is idle. Thus, the hook deals with the above problem (b), but -;; unfortunately it makes (a) worse and does not address (c) at all. -;; -;; I freely admit that `redisplay-end-trigger-functions' and, to a much lesser -;; extent, `window-size-change-functions' are not pretty. However, I feel that -;; a `window-scroll-functions' feature is cleaner than a `pre-idle-hook', and -;; the result is faster and smaller, less intrusive and more targeted, code. -;; Since `pre-idle-hook' is pretty much like `post-command-hook', there is no -;; point in making this version of lazy-lock.el work with it. Anyway, that's -;; Lit 30 of my humble opinion. -;; -;; - Version 1 stealth fontification is also implemented by placing a function -;; on `post-command-hook'. This function waits for a given amount of time, -;; and, if Emacs remains idle, fontifies where necessary. Again, there are a -;; number of problems with using `post-command-hook': -;; -;; (a) Functions on `post-command-hook' are run sequentially, so this function -;; can interfere with other functions on the hook, and vice versa. -;; (b) This function waits for a given amount of time, so it can interfere with -;; various features that are dealt with by Emacs after a command, e.g., -;; region highlighting, asynchronous updating and keystroke echoing. -;; (c) Fontification may be required during a command, when `post-command-hook' -;; is not run. (Version 2 deferred fontification only.) -;; -;; Again, `post-command-hook' is completely inappropriate for lazy-lock.el. -;; Richard Stallman and Morten Welinder implemented internal Timers and Idle -;; Timers for Emacs 19.31. Functions can be run independently at given times -;; or after given amounts of idle time. Thus, the feature deals with the above -;; problems (a), (b) and (c). Version 2 deferral and stealth are implemented -;; by functions on Idle Timers. (A function on XEmacs' `pre-idle-hook' is -;; similar to an Emacs Idle Timer function with a fixed zero second timeout.) - -;; - Version 1 has the following problems (relative to version 2): -;; -;; (a) It is slow when it does its job. -;; (b) It does not always do its job when it should. -;; (c) It slows all interaction (when it doesn't need to do its job). -;; (d) It interferes with other package functions on `post-command-hook'. -;; (e) It interferes with Emacs things within the read-eval loop. -;; -;; Ben's hacked-up lazy-lock.el 1.14 almost solved (b) but made (c) worse. -;; -;; - Version 2 has the following additional features (relative to version 1): -;; -;; (a) It can defer fontification (both on-the-fly and on-scrolling). -;; (b) It can fontify contextually (syntactically true on-the-fly). - -;; Caveats: -;; -;; Lazy Lock mode does not work efficiently with Outline mode. -;; This is because when in Outline mode, although text may be not visible to -;; you in the window, the text is visible to Emacs Lisp code (not surprisingly) -;; and Lazy Lock fontifies it mercilessly. Maybe it will be fixed one day. -;; -;; Because buffer text is not necessarily fontified, other packages that expect -;; buffer text to be fontified in Font Lock mode either might not work as -;; expected, or might not display buffer text as expected. An example of the -;; latter is `occur', which copies lines of buffer text into another buffer. -;; -;; In Emacs 19.30, Lazy Lock mode does not ensure that an existing buffer is -;; fontified if it is made visible via a minibuffer-less command that replaces -;; an existing window's buffer (e.g., via the Buffers menu). Upgrade! -;; -;; In Emacs 19.30, Lazy Lock mode does not work well with Transient Mark mode -;; or modes based on Comint mode (e.g., Shell mode), and also interferes with -;; the echoing of keystrokes in the minibuffer. This is because of the way -;; deferral and stealth have to be implemented for Emacs 19.30. Upgrade! -;; -;; Currently XEmacs does not have the features to support this version of -;; lazy-lock.el. Maybe it will one day. - -;; History: -;; -;; 1.15--2.00: -;; - Rewrite for Emacs 19.30 and the features rms added to support lazy-lock.el -;; so that it could work correctly and efficiently. -;; - Many thanks to those who reported bugs, fixed bugs, made suggestions or -;; otherwise contributed in the version 1 cycle; Jari Aalto, Kevin Broadey, -;; Ulrik Dickow, Bill Dubuque, Bob Glickstein, Boris Goldowsky, -;; Jonas Jarnestrom, David Karr, Michael Kifer, Erik Naggum, Rick Sladkey, -;; Jim Thompson, Ben Wing, Ilya Zakharevich, and Richard Stallman. -;; 2.00--2.01: -;; - Made `lazy-lock-fontify-after-command' always `sit-for' and so redisplay -;; - Use `buffer-name' not `buffer-live-p' (Bill Dubuque hint) -;; - Made `lazy-lock-install' do `add-to-list' not `setq' of `current-buffer' -;; - Made `lazy-lock-fontify-after-install' loop over buffer list -;; - Made `lazy-lock-arrange-before-change' to arrange `window-end' triggering -;; - Made `lazy-lock-let-buffer-state' wrap both `befter-change-functions' -;; - Made `lazy-lock-fontify-region' do `condition-case' (Hyman Rosen report) -;; 2.01--2.02: -;; - Use `buffer-live-p' as `buffer-name' can barf (Richard Stanton report) -;; - Made `lazy-lock-install' set `font-lock-fontified' (Kevin Davidson report) -;; - Made `lazy-lock-install' add hooks only if needed -;; - Made `lazy-lock-unstall' add `font-lock-after-change-function' if needed -;; 2.02--2.03: -;; - Made `lazy-lock-fontify-region' do `condition-case' for `quit' too -;; - Made `lazy-lock-mode' respect the value of `font-lock-inhibit-thing-lock' -;; - Added `lazy-lock-after-unfontify-buffer' -;; - Removed `lazy-lock-fontify-after-install' hack -;; - Made `lazy-lock-fontify-after-scroll' not `set-buffer' to `window-buffer' -;; - Made `lazy-lock-fontify-after-trigger' not `set-buffer' to `window-buffer' -;; - Made `lazy-lock-fontify-after-idle' be interruptible (Scott Burson hint) -;; 2.03--2.04: -;; - Rewrite for Emacs 19.31 idle timers -;; - Renamed `buffer-windows' to `get-buffer-window-list' -;; - Removed `buffer-live-p' -;; - Made `lazy-lock-defer-after-change' always save `current-buffer' -;; - Made `lazy-lock-fontify-after-defer' just process buffers -;; - Made `lazy-lock-install-hooks' add hooks correctly (Kevin Broadey report) -;; - Made `lazy-lock-install' cope if `lazy-lock-defer-time' is a list -;; 2.04--2.05: -;; - Rewrite for Common Lisp macros -;; - Added `do-while' macro -;; - Renamed `lazy-lock-let-buffer-state' macro to `save-buffer-state' -;; - Returned `lazy-lock-fontify-after-install' hack (Darren Hall hint) -;; - Added `lazy-lock-defer-on-scrolling' functionality (Scott Byer hint) -;; - Made `lazy-lock-mode' wrap `font-lock-support-mode' -;; 2.05--2.06: -;; - Made `lazy-lock-fontify-after-defer' swap correctly (Scott Byer report) -;; 2.06--2.07: -;; - Added `lazy-lock-stealth-load' functionality (Rob Hooft hint) -;; - Made `lazy-lock-unstall' call `lazy-lock-fontify-region' if needed -;; - Made `lazy-lock-mode' call `lazy-lock-unstall' only if needed -;; - Made `lazy-lock-defer-after-scroll' do `set-window-redisplay-end-trigger' -;; - Added `lazy-lock-defer-contextually' functionality -;; - Added `lazy-lock-defer-on-the-fly' from `lazy-lock-defer-time' -;; - Renamed `lazy-lock-defer-driven' to `lazy-lock-defer-on-scrolling' -;; - Removed `lazy-lock-submit-bug-report' and bade farewell -;; 2.07--2.08: -;; - Made `lazy-lock-fontify-conservatively' fontify around `window-point' -;; - Made `save-buffer-state' wrap `inhibit-point-motion-hooks' -;; - Added Custom support -;; 2.08--2.09: -;; - Removed `byte-*' variables from `eval-when-compile' (Erik Naggum hint) -;; - Made various wrapping `inhibit-point-motion-hooks' (Vinicius Latorre hint) -;; - Made `lazy-lock-fontify-after-idle' wrap `minibuffer-auto-raise' -;; - Made `lazy-lock-fontify-after-defer' paranoid about deferred buffers -;; 2.09--2.10: -;; - Use `window-end' UPDATE arg for Emacs 20.4 and later. -;; - Made deferral `widen' before unfontifying (Dan Nicolaescu report) -;; - Use `lazy-lock-fontify-after-visage' for hideshow.el (Dan Nicolaescu hint) -;; - Use `other' widget where possible (Andreas Schwab fix) -;; 2.10--2.11: -;; - Used `with-temp-message' where possible to make messages temporary. - -;;; Code: - -(require 'font-lock) -(eval-when-compile (require 'cl-lib)) - -(eval-when-compile - ;; - ;; We use this for clarity and speed. Naughty but nice. - (defmacro do-while (test &rest body) - "(do-while TEST BODY...): eval BODY... and repeat if TEST yields non-nil. -The order of execution is thus BODY, TEST, BODY, TEST and so on -until TEST returns nil." - (declare (indent 1) (debug t)) - `(while (progn ,@body ,test)))) - -(defgroup lazy-lock nil - "Font Lock support mode to fontify lazily." - :group 'font-lock) - -(defvar lazy-lock-mode nil) ; Whether we are turned on. -(defvar lazy-lock-buffers nil) ; For deferral. -(defvar lazy-lock-timers (cons nil nil)) ; For deferral and stealth. - -;; User Variables: - -(defcustom lazy-lock-minimum-size 25600 - "Minimum size of a buffer for demand-driven fontification. -On-demand fontification occurs if the buffer size is greater than this value. -If nil, means demand-driven fontification is never performed. -If a list, each element should be a cons pair of the form (MAJOR-MODE . SIZE), -where MAJOR-MODE is a symbol or t (meaning the default). For example: - ((c-mode . 25600) (c++-mode . 25600) (rmail-mode . 1048576)) -means that the minimum size is 25K for buffers in C or C++ modes, one megabyte -for buffers in Rmail mode, and size is irrelevant otherwise. - -The value of this variable is used when Lazy Lock mode is turned on." - :type '(choice (const :tag "none" nil) - (integer :tag "size") - (repeat :menu-tag "mode specific" :tag "mode specific" - :value ((t . nil)) - (cons :tag "Instance" - (radio :tag "Mode" - (const :tag "all" t) - (symbol :tag "name")) - (radio :tag "Size" - (const :tag "none" nil) - (integer :tag "size")))))) - -(defcustom lazy-lock-defer-on-the-fly t - "If non-nil, means fontification after a change should be deferred. -If nil, means on-the-fly fontification is performed. This means when changes -occur in the buffer, those areas are immediately fontified. -If a list, it should be a list of `major-mode' symbol names for which deferred -fontification should occur. The sense of the list is negated if it begins with -`not'. For example: - (c-mode c++-mode) -means that on-the-fly fontification is deferred for buffers in C and C++ modes -only, and deferral does not occur otherwise. - -The value of this variable is used when Lazy Lock mode is turned on." - :type '(choice (const :tag "never" nil) - (const :tag "always" t) - (set :menu-tag "mode specific" :tag "modes" - :value (not) - (const :tag "Except" not) - (repeat :inline t (symbol :tag "mode"))))) - -(defcustom lazy-lock-defer-on-scrolling nil - "If non-nil, means fontification after a scroll should be deferred. -If nil, means demand-driven fontification is performed. This means when -scrolling into unfontified areas of the buffer, those areas are immediately -fontified. Thus scrolling never presents unfontified areas. However, since -fontification occurs during scrolling, scrolling may be slow. -If t, means defer-driven fontification is performed. This means fontification -of those areas is deferred. Thus scrolling may present momentarily unfontified -areas. However, since fontification does not occur during scrolling, scrolling -will be faster than demand-driven fontification. -If any other value, e.g., `eventually', means demand-driven fontification is -performed until the buffer is fontified, then buffer fontification becomes -defer-driven. Thus scrolling never presents unfontified areas until the buffer -is first fontified, after which subsequent scrolling may present future buffer -insertions momentarily unfontified. However, since fontification does not -occur during scrolling after the buffer is first fontified, scrolling will -become faster. (But, since contextual changes continually occur, such a value -makes little sense if `lazy-lock-defer-contextually' is non-nil.) - -The value of this variable is used when Lazy Lock mode is turned on." - :type '(choice (const :tag "never" nil) - (const :tag "always" t) - (other :tag "eventually" eventually))) - -(defcustom lazy-lock-defer-contextually 'syntax-driven - "If non-nil, means deferred fontification should be syntactically true. -If nil, means deferred fontification occurs only on those lines modified. This -means where modification on a line causes syntactic change on subsequent lines, -those subsequent lines are not refontified to reflect their new context. -If t, means deferred fontification occurs on those lines modified and all -subsequent lines. This means those subsequent lines are refontified to reflect -their new syntactic context, either immediately or when scrolling into them. -If any other value, e.g., `syntax-driven', means deferred syntactically true -fontification occurs only if syntactic fontification is performed using the -buffer mode's syntax table, i.e., only if `font-lock-keywords-only' is nil. - -The value of this variable is used when Lazy Lock mode is turned on." - :type '(choice (const :tag "never" nil) - (const :tag "always" t) - (other :tag "syntax-driven" syntax-driven))) - -(defcustom lazy-lock-defer-time 0.25 - "Time in seconds to delay before beginning deferred fontification. -Deferred fontification occurs if there is no input within this time. -If nil, means fontification is never deferred, regardless of the values of the -variables `lazy-lock-defer-on-the-fly', `lazy-lock-defer-on-scrolling' and -`lazy-lock-defer-contextually'. - -The value of this variable is used when Lazy Lock mode is turned on." - :type '(choice (const :tag "never" nil) - (number :tag "seconds"))) - -(defcustom lazy-lock-stealth-time 30 - "Time in seconds to delay before beginning stealth fontification. -Stealth fontification occurs if there is no input within this time. -If nil, means stealth fontification is never performed. - -The value of this variable is used when Lazy Lock mode is turned on." - :type '(choice (const :tag "never" nil) - (number :tag "seconds"))) - -(defcustom lazy-lock-stealth-lines (if font-lock-maximum-decoration 100 250) - "Maximum size of a chunk of stealth fontification. -Each iteration of stealth fontification can fontify this number of lines. -To speed up input response during stealth fontification, at the cost of stealth -taking longer to fontify, you could reduce the value of this variable." - :type '(integer :tag "lines")) - -(defcustom lazy-lock-stealth-load - (if (condition-case nil (load-average) (error)) 200) - "Load in percentage above which stealth fontification is suspended. -Stealth fontification pauses when the system short-term load average (as -returned by the function `load-average' if supported) goes above this level, -thus reducing the demand that stealth fontification makes on the system. -If nil, means stealth fontification is never suspended. -To reduce machine load during stealth fontification, at the cost of stealth -taking longer to fontify, you could reduce the value of this variable. -See also `lazy-lock-stealth-nice'." - :type (if (condition-case nil (load-average) (error)) - '(choice (const :tag "never" nil) - (integer :tag "load")) - '(const :format "%t: unsupported\n" nil))) - -(defcustom lazy-lock-stealth-nice 0.125 - "Time in seconds to pause between chunks of stealth fontification. -Each iteration of stealth fontification is separated by this amount of time, -thus reducing the demand that stealth fontification makes on the system. -If nil, means stealth fontification is never paused. -To reduce machine load during stealth fontification, at the cost of stealth -taking longer to fontify, you could increase the value of this variable. -See also `lazy-lock-stealth-load'." - :type '(choice (const :tag "never" nil) - (number :tag "seconds"))) - -(defcustom lazy-lock-stealth-verbose - (and (not lazy-lock-defer-contextually) (not (null font-lock-verbose))) - "If non-nil, means stealth fontification should show status messages." - :type 'boolean) - -;; User Functions: - -;;;###autoload -(defun lazy-lock-mode (&optional arg) - "Toggle Lazy Lock mode. -With arg, turn Lazy Lock mode on if and only if arg is positive. Enable it -automatically in your `~/.emacs' by: - - (setq font-lock-support-mode \\='lazy-lock-mode) - -For a newer font-lock support mode with similar functionality, see -`jit-lock-mode'. Eventually, Lazy Lock mode will be deprecated in -JIT Lock's favor. - -When Lazy Lock mode is enabled, fontification can be lazy in a number of ways: - -- Demand-driven buffer fontification if `lazy-lock-minimum-size' is non-nil. - This means initial fontification does not occur if the buffer is greater than - `lazy-lock-minimum-size' characters in length. Instead, fontification occurs - when necessary, such as when scrolling through the buffer would otherwise - reveal unfontified areas. This is useful if buffer fontification is too slow - for large buffers. - -- Deferred scroll fontification if `lazy-lock-defer-on-scrolling' is non-nil. - This means demand-driven fontification does not occur as you scroll. - Instead, fontification is deferred until after `lazy-lock-defer-time' seconds - of Emacs idle time, while Emacs remains idle. This is useful if - fontification is too slow to keep up with scrolling. - -- Deferred on-the-fly fontification if `lazy-lock-defer-on-the-fly' is non-nil. - This means on-the-fly fontification does not occur as you type. Instead, - fontification is deferred until after `lazy-lock-defer-time' seconds of Emacs - idle time, while Emacs remains idle. This is useful if fontification is too - slow to keep up with your typing. - -- Deferred context fontification if `lazy-lock-defer-contextually' is non-nil. - This means fontification updates the buffer corresponding to true syntactic - context, after `lazy-lock-defer-time' seconds of Emacs idle time, while Emacs - remains idle. Otherwise, fontification occurs on modified lines only, and - subsequent lines can remain fontified corresponding to previous syntactic - contexts. This is useful where strings or comments span lines. - -- Stealthy buffer fontification if `lazy-lock-stealth-time' is non-nil. - This means remaining unfontified areas of buffers are fontified if Emacs has - been idle for `lazy-lock-stealth-time' seconds, while Emacs remains idle. - This is useful if any buffer has any deferred fontification. - -Basic Font Lock mode on-the-fly fontification behavior fontifies modified -lines only. Thus, if `lazy-lock-defer-contextually' is non-nil, Lazy Lock mode -on-the-fly fontification may fontify differently, albeit correctly. In any -event, to refontify some lines you can use \\[font-lock-fontify-block]. - -Stealth fontification only occurs while the system remains unloaded. -If the system load rises above `lazy-lock-stealth-load' percent, stealth -fontification is suspended. Stealth fontification intensity is controlled via -the variable `lazy-lock-stealth-nice' and `lazy-lock-stealth-lines', and -verbosity is controlled via the variable `lazy-lock-stealth-verbose'." - (interactive "P") - (let* ((was-on lazy-lock-mode) - (now-on (unless (memq 'lazy-lock-mode font-lock-inhibit-thing-lock) - (if arg (> (prefix-numeric-value arg) 0) (not was-on))))) - (cond ((and now-on (not font-lock-mode)) - ;; Turned on `lazy-lock-mode' rather than `font-lock-mode'. - (message "Use font-lock-support-mode rather than calling lazy-lock-mode") - (sit-for 2)) - (now-on - ;; Turn ourselves on. - (set (make-local-variable 'lazy-lock-mode) t) - (lazy-lock-install)) - (was-on - ;; Turn ourselves off. - (set (make-local-variable 'lazy-lock-mode) nil) - (lazy-lock-unstall))))) - -;;;###autoload -(defun turn-on-lazy-lock () - "Unconditionally turn on Lazy Lock mode." - (lazy-lock-mode t)) - -(defun lazy-lock-install () - (let ((min-size (font-lock-value-in-major-mode lazy-lock-minimum-size)) - (defer-change (and lazy-lock-defer-time lazy-lock-defer-on-the-fly)) - (defer-scroll (and lazy-lock-defer-time lazy-lock-defer-on-scrolling)) - (defer-context (and lazy-lock-defer-time lazy-lock-defer-contextually - (or (eq lazy-lock-defer-contextually t) - (null font-lock-keywords-only))))) - ;; - ;; Tell Font Lock whether Lazy Lock will do fontification. - (make-local-variable 'font-lock-fontified) - (setq font-lock-fontified (and min-size (>= (buffer-size) min-size))) - ;; - ;; Add the text properties and fontify. - (if (not font-lock-fontified) - (lazy-lock-after-fontify-buffer) - ;; Make sure we fontify in any existing windows showing the buffer. - (let ((windows (get-buffer-window-list (current-buffer) 'nomini t))) - (lazy-lock-after-unfontify-buffer) - (while windows - (lazy-lock-fontify-conservatively (car windows)) - (setq windows (cdr windows))))) - ;; - ;; Add the fontification hooks. - (lazy-lock-install-hooks - font-lock-fontified - (cond ((eq (car-safe defer-change) 'not) - (not (memq major-mode (cdr defer-change)))) - ((listp defer-change) - (memq major-mode defer-change)) - (t - defer-change)) - (eq defer-scroll t) - defer-context) - ;; - ;; Add the fontification timers. - (lazy-lock-install-timers - (if (or defer-change defer-scroll defer-context) lazy-lock-defer-time) - lazy-lock-stealth-time))) - -(defun lazy-lock-install-hooks (fontifying - defer-change defer-scroll defer-context) - ;; - ;; Add hook if lazy-lock.el is fontifying on scrolling or is deferring. - (when (or fontifying defer-change defer-scroll defer-context) - (add-hook 'window-scroll-functions (if defer-scroll - #'lazy-lock-defer-after-scroll - #'lazy-lock-fontify-after-scroll) - nil t)) - ;; - ;; Add hook if lazy-lock.el is fontifying and is not deferring changes. - (when (and fontifying (not defer-change) (not defer-context)) - (add-hook 'before-change-functions #'lazy-lock-arrange-before-change nil t)) - ;; - ;; Replace Font Lock mode hook. - (remove-hook 'after-change-functions #'font-lock-after-change-function t) - (add-hook 'after-change-functions - (cond ((and defer-change defer-context) - #'lazy-lock-defer-rest-after-change) - (defer-change - #'lazy-lock-defer-line-after-change) - (defer-context - #'lazy-lock-fontify-rest-after-change) - (t - #'lazy-lock-fontify-line-after-change)) - nil t) - ;; - ;; Add package-specific hook. - (add-hook 'outline-view-change-hook #'lazy-lock-fontify-after-visage nil t) - (add-hook 'hs-hide-hook #'lazy-lock-fontify-after-visage nil t)) - -(defun lazy-lock-install-timers (dtime stime) - ;; Schedule or re-schedule the deferral and stealth timers. - ;; The layout of `lazy-lock-timers' is: - ;; ((DEFER-TIME . DEFER-TIMER) (STEALTH-TIME . STEALTH-TIMER) - ;; If an idle timeout has changed, cancel the existing idle timer (if there - ;; is one) and schedule a new one (if the new idle timeout is non-nil). - (unless (eq dtime (car (car lazy-lock-timers))) - (let ((defer (car lazy-lock-timers))) - (when (cdr defer) - (cancel-timer (cdr defer))) - (setcar lazy-lock-timers (cons dtime (and dtime - (run-with-idle-timer dtime t #'lazy-lock-fontify-after-defer)))))) - (unless (eq stime (car (cdr lazy-lock-timers))) - (let ((stealth (cdr lazy-lock-timers))) - (when (cdr stealth) - (cancel-timer (cdr stealth))) - (setcdr lazy-lock-timers (cons stime (and stime - (run-with-idle-timer stime t #'lazy-lock-fontify-after-idle))))))) - -(defun lazy-lock-unstall () - ;; - ;; If Font Lock mode is still enabled, make sure that the buffer is - ;; fontified, and reinstall its hook. We must do this first. - (when font-lock-mode - (when (lazy-lock-unfontified-p) - (let ((verbose (if (numberp font-lock-verbose) - (> (buffer-size) font-lock-verbose) - font-lock-verbose))) - (with-temp-message - (when verbose - (format "Fontifying %s..." (buffer-name))) - ;; Make sure we fontify etc. in the whole buffer. - (save-restriction - (widen) - (lazy-lock-fontify-region (point-min) (point-max)))))) - (add-hook 'after-change-functions #'font-lock-after-change-function nil t)) - ;; - ;; Remove the text properties. - (lazy-lock-after-unfontify-buffer) - ;; - ;; Remove the fontification hooks. - (remove-hook 'window-scroll-functions #'lazy-lock-fontify-after-scroll t) - (remove-hook 'window-scroll-functions #'lazy-lock-defer-after-scroll t) - (remove-hook 'before-change-functions #'lazy-lock-arrange-before-change t) - (remove-hook 'after-change-functions #'lazy-lock-fontify-line-after-change t) - (remove-hook 'after-change-functions #'lazy-lock-fontify-rest-after-change t) - (remove-hook 'after-change-functions #'lazy-lock-defer-line-after-change t) - (remove-hook 'after-change-functions #'lazy-lock-defer-rest-after-change t) - (remove-hook 'outline-view-change-hook #'lazy-lock-fontify-after-visage t) - (remove-hook 'hs-hide-hook #'lazy-lock-fontify-after-visage t)) - -;; Hook functions. - -;; Lazy Lock mode intervenes when (1) a previously invisible buffer region -;; becomes visible, i.e., for demand- or defer-driven on-the-scroll -;; fontification, (2) a buffer modification occurs, i.e., for defer-driven -;; on-the-fly fontification, (3) Emacs becomes idle, i.e., for fontification of -;; deferred fontification and stealth fontification, and (4) other special -;; occasions. - -;; 1. There are three ways whereby this can happen. -;; -;; (a) Scrolling the window, either explicitly (e.g., `scroll-up') or -;; implicitly (e.g., `search-forward'). Here, `window-start' changes. -;; Fontification occurs by adding `lazy-lock-fontify-after-scroll' (for -;; demand-driven fontification) or `lazy-lock-defer-after-scroll' (for -;; defer-driven fontification) to the hook `window-scroll-functions'. - -(defun lazy-lock-fontify-after-scroll (window window-start) - ;; Called from `window-scroll-functions'. - ;; Fontify WINDOW from WINDOW-START following the scroll. - (let ((inhibit-point-motion-hooks t)) - (lazy-lock-fontify-region window-start (window-end window t))) - ;; A prior deletion that did not cause scrolling, followed by a scroll, would - ;; result in an unnecessary trigger after this if we did not cancel it now. - (set-window-redisplay-end-trigger window nil)) - -(defun lazy-lock-defer-after-scroll (window _window-start) - ;; Called from `window-scroll-functions'. - ;; Defer fontification following the scroll. Save the current buffer so that - ;; we subsequently fontify in all windows showing the buffer. - (unless (memq (current-buffer) lazy-lock-buffers) - (push (current-buffer) lazy-lock-buffers)) - ;; A prior deletion that did not cause scrolling, followed by a scroll, would - ;; result in an unnecessary trigger after this if we did not cancel it now. - (set-window-redisplay-end-trigger window nil)) - -;; (b) Resizing the window, either explicitly (e.g., `enlarge-window') or -;; implicitly (e.g., `delete-other-windows'). Here, `window-end' changes. -;; Fontification occurs by adding `lazy-lock-fontify-after-resize' to the -;; hook `window-size-change-functions'. - -(defun lazy-lock-fontify-after-resize (frame) - ;; Called from `window-size-change-functions'. - ;; Fontify windows in FRAME following the resize. We cannot use - ;; `window-start' or `window-end' so we fontify conservatively. - (save-excursion - (save-selected-window - (select-frame frame) - (walk-windows (function (lambda (window) - (set-buffer (window-buffer window)) - (when lazy-lock-mode - (lazy-lock-fontify-conservatively window)) - (set-window-redisplay-end-trigger window nil))) - 'nomini frame)))) - -;; (c) Deletion in the buffer. Here, a `window-end' marker can become visible. -;; Fontification occurs by adding `lazy-lock-arrange-before-change' to -;; `before-change-functions' and `lazy-lock-fontify-after-trigger' to the -;; hook `redisplay-end-trigger-functions'. Before every deletion, the -;; marker `window-redisplay-end-trigger' position is set to the soon-to-be -;; changed `window-end' position. If the marker becomes visible, -;; `lazy-lock-fontify-after-trigger' gets called. Ouch. Note that we only -;; have to deal with this eventuality if there is no on-the-fly deferral. - -(defun lazy-lock-arrange-before-change (beg end) - ;; Called from `before-change-functions'. - ;; Arrange that if text becomes visible it will be fontified (if a deletion - ;; is pending, text might become visible at the bottom). - (unless (eq beg end) - (let ((windows (get-buffer-window-list (current-buffer) 'nomini t)) window) - (while windows - (setq window (car windows)) - (unless (markerp (window-redisplay-end-trigger window)) - (set-window-redisplay-end-trigger window (make-marker))) - (set-marker (window-redisplay-end-trigger window) (window-end window)) - (setq windows (cdr windows)))))) - -(defun lazy-lock-fontify-after-trigger (window trigger-point) - ;; Called from `redisplay-end-trigger-functions'. - ;; Fontify WINDOW from TRIGGER-POINT following the redisplay. - ;; We could probably just use `lazy-lock-fontify-after-scroll' without loss: - ;; (inline (lazy-lock-fontify-after-scroll window (window-start window))) - (let ((inhibit-point-motion-hooks t)) - (lazy-lock-fontify-region trigger-point (window-end window t)))) - -;; 2. Modified text must be marked as unfontified so it can be identified and -;; fontified later when Emacs is idle. Deferral occurs by adding one of -;; `lazy-lock-fontify-*-after-change' (for on-the-fly fontification) or -;; `lazy-lock-defer-*-after-change' (for deferred fontification) to the -;; hook `after-change-functions'. - -(defalias 'lazy-lock-fontify-line-after-change - ;; Called from `after-change-functions'. - ;; Fontify the current change. - #'font-lock-after-change-function) - -(defun lazy-lock-fontify-rest-after-change (beg end old-len) - ;; Called from `after-change-functions'. - ;; Fontify the current change and defer fontification of the rest of the - ;; buffer. Save the current buffer so that we subsequently fontify in all - ;; windows showing the buffer. - (lazy-lock-fontify-line-after-change beg end old-len) - (with-silent-modifications - (unless (memq (current-buffer) lazy-lock-buffers) - (push (current-buffer) lazy-lock-buffers)) - (save-restriction - (widen) - (remove-text-properties end (point-max) '(lazy-lock nil))))) - -(defun lazy-lock-defer-line-after-change (beg end _old-len) - ;; Called from `after-change-functions'. - ;; Defer fontification of the current change. Save the current buffer so - ;; that we subsequently fontify in all windows showing the buffer. - (with-silent-modifications - (unless (memq (current-buffer) lazy-lock-buffers) - (push (current-buffer) lazy-lock-buffers)) - (remove-text-properties (max (1- beg) (point-min)) - (min (1+ end) (point-max)) - '(lazy-lock nil)))) - -(defun lazy-lock-defer-rest-after-change (beg _end _old-len) - ;; Called from `after-change-functions'. - ;; Defer fontification of the rest of the buffer. Save the current buffer so - ;; that we subsequently fontify in all windows showing the buffer. - (with-silent-modifications - (unless (memq (current-buffer) lazy-lock-buffers) - (push (current-buffer) lazy-lock-buffers)) - (save-restriction - (widen) - (remove-text-properties (max (1- beg) (point-min)) - (point-max) - '(lazy-lock nil))))) - -;; 3. Deferred fontification and stealth fontification are done from these two -;; functions. They are set up as Idle Timers. - -(defun lazy-lock-fontify-after-defer () - ;; Called from `timer-idle-list'. - ;; Fontify all windows where deferral has occurred for its buffer. - (save-excursion - (while (and lazy-lock-buffers (not (input-pending-p))) - (let ((buffer (car lazy-lock-buffers)) windows) - ;; Paranoia: check that the buffer is still live and Lazy Lock mode on. - (when (buffer-live-p buffer) - (set-buffer buffer) - (when lazy-lock-mode - (setq windows (get-buffer-window-list buffer 'nomini t)) - (while windows - (lazy-lock-fontify-window (car windows)) - (setq windows (cdr windows))))) - (setq lazy-lock-buffers (cdr lazy-lock-buffers))))) - ;; Add hook if fontification should now be defer-driven in this buffer. - (when (and lazy-lock-mode lazy-lock-defer-on-scrolling - (memq #'lazy-lock-fontify-after-scroll window-scroll-functions) - (not (or (input-pending-p) (lazy-lock-unfontified-p)))) - (remove-hook 'window-scroll-functions #'lazy-lock-fontify-after-scroll t) - (add-hook 'window-scroll-functions #'lazy-lock-defer-after-scroll nil t))) - -(defun lazy-lock-fontify-after-idle () - ;; Called from `timer-idle-list'. - ;; Fontify all buffers that need it, stealthily while idle. - (unless (or executing-kbd-macro (window-minibuffer-p (selected-window))) - ;; Loop over all buffers, fontify stealthily for each if necessary. - (let ((buffers (buffer-list)) (continue t) - message message-log-max minibuffer-auto-raise) - (save-excursion - (do-while (and buffers continue) - (set-buffer (car buffers)) - (if (not (and lazy-lock-mode (lazy-lock-unfontified-p))) - (setq continue (not (input-pending-p))) - ;; Fontify regions in this buffer while there is no input. - (with-temp-message - (when lazy-lock-stealth-verbose - "Fontifying stealthily...") - (do-while (and (lazy-lock-unfontified-p) continue) - (if (and lazy-lock-stealth-load - (> (car (load-average)) lazy-lock-stealth-load)) - ;; Wait a while before continuing with the loop. - (progn - (when message - (message "Fontifying stealthily...suspended") - (setq message nil)) - (setq continue (sit-for (or lazy-lock-stealth-time 30)))) - ;; Fontify a chunk. - (when lazy-lock-stealth-verbose - (if message - (message "Fontifying stealthily... %2d%% of %s" - (lazy-lock-percent-fontified) (buffer-name)) - (message "Fontifying stealthily...") - (setq message t))) - ;; Current buffer may have changed during `sit-for'. - (set-buffer (car buffers)) - (lazy-lock-fontify-chunk) - (setq continue (sit-for (or lazy-lock-stealth-nice 0))))))) - (setq buffers (cdr buffers))))))) - -;; 4. Special circumstances. - -(defun lazy-lock-fontify-after-visage () - ;; Called from `outline-view-change-hook' and `hs-hide-hook'. - ;; Fontify windows showing the current buffer, as its visibility has changed. - ;; This is a conspiracy hack between lazy-lock.el, outline.el and - ;; hideshow.el. - (let ((windows (get-buffer-window-list (current-buffer) 'nomini t))) - (while windows - (lazy-lock-fontify-conservatively (car windows)) - (setq windows (cdr windows))))) - -(defun lazy-lock-after-fontify-buffer () - ;; Called from `font-lock-after-fontify-buffer'. - ;; Mark the current buffer as fontified. - ;; This is a conspiracy hack between lazy-lock.el and font-lock.el. - (with-silent-modifications - (add-text-properties (point-min) (point-max) '(lazy-lock t)))) - -(defun lazy-lock-after-unfontify-buffer () - ;; Called from `font-lock-after-unfontify-buffer'. - ;; Mark the current buffer as unfontified. - ;; This is a conspiracy hack between lazy-lock.el and font-lock.el. - (with-silent-modifications - (remove-text-properties (point-min) (point-max) '(lazy-lock nil)))) - -;; Fontification functions. - -;; If packages want to ensure that some region of the buffer is fontified, they -;; should use this function. For an example, see ps-print.el. -(defun lazy-lock-fontify-region (beg end) - ;; Fontify between BEG and END, where necessary, in the current buffer. - (save-restriction - (widen) - (when (setq beg (text-property-any beg end 'lazy-lock nil)) - (save-excursion - (with-silent-modifications - (let ((inhibit-point-motion-hooks t)) - ;; Find successive unfontified regions between BEG and END. - (condition-case data - (do-while beg - (let ((next (or (text-property-any beg end 'lazy-lock t) - end))) - ;; Make sure the region end points are at beginning of line. - (goto-char beg) - (unless (bolp) - (beginning-of-line) - (setq beg (point))) - (goto-char next) - (unless (bolp) - (forward-line) - (setq next (point))) - ;; Fontify the region, then flag it as fontified. - (font-lock-fontify-region beg next) - (add-text-properties beg next '(lazy-lock t)) - (setq beg (text-property-any next end 'lazy-lock nil)))) - ((error quit) (message "Fontifying region...%s" data))))))))) - -(defun lazy-lock-fontify-chunk () - ;; Fontify the nearest chunk, for stealth, in the current buffer. - (let ((inhibit-point-motion-hooks t)) - (save-excursion - (save-restriction - (widen) - ;; Move to end of line in case the character at point is not fontified. - (end-of-line) - ;; Find where the previous (next) unfontified regions end (begin). - (let ((prev (previous-single-property-change (point) 'lazy-lock)) - (next (text-property-any (point) (point-max) 'lazy-lock nil))) - ;; Fontify from the nearest unfontified position. - (if (or (null prev) (and next (< (- next (point)) (- (point) prev)))) - ;; The next, or neither, region is the nearest not fontified. - (lazy-lock-fontify-region - (progn (goto-char (or next (point-min))) - (beginning-of-line) - (point)) - (progn (goto-char (or next (point-min))) - (forward-line lazy-lock-stealth-lines) - (point))) - ;; The previous region is the nearest not fontified. - (lazy-lock-fontify-region - (progn (goto-char prev) - (forward-line (- lazy-lock-stealth-lines)) - (point)) - (progn (goto-char prev) - (forward-line) - (point))))))))) - -(defun lazy-lock-fontify-window (window) - ;; Fontify in WINDOW between `window-start' and `window-end'. - ;; We can only do this when we can use `window-start' and `window-end'. - (with-current-buffer (window-buffer window) - (lazy-lock-fontify-region (window-start window) (window-end window)))) - -(defun lazy-lock-fontify-conservatively (window) - ;; Fontify in WINDOW conservatively around point. - ;; Where we cannot use `window-start' and `window-end' we do `window-height' - ;; lines around point. That way we guarantee to have done enough. - (with-current-buffer (window-buffer window) - (let ((inhibit-point-motion-hooks t)) - (lazy-lock-fontify-region - (save-excursion - (goto-char (window-point window)) - (vertical-motion (- (window-height window)) window) (point)) - (save-excursion - (goto-char (window-point window)) - (vertical-motion (window-height window) window) (point)))))) - -(defun lazy-lock-unfontified-p () - ;; Return non-nil if there is anywhere still to be fontified. - (save-restriction - (widen) - (text-property-any (point-min) (point-max) 'lazy-lock nil))) - -(defun lazy-lock-percent-fontified () - ;; Return the percentage (of characters) of the buffer that are fontified. - (save-restriction - (widen) - (let ((beg (point-min)) (size 0) next) - ;; Find where the next fontified region begins. - (while (setq beg (text-property-any beg (point-max) 'lazy-lock t)) - (setq next (or (text-property-any beg (point-max) 'lazy-lock nil) - (point-max))) - (cl-incf size (- next beg)) - (setq beg next)) - ;; Float because using integer multiplication will frequently overflow. - (truncate (* (/ (float size) (point-max)) 100))))) - -;; Version dependent workarounds and fixes. - -(when (consp lazy-lock-defer-time) - ;; - ;; In 2.06.04 and below, `lazy-lock-defer-time' could specify modes and time. - (with-output-to-temp-buffer "*Help*" - (princ "The value of the variable `lazy-lock-defer-time' was\n ") - (princ lazy-lock-defer-time) - (princ "\n") - (princ "This variable cannot now be a list of modes and time,\n") - (princ "so instead use ") - (princ (substitute-command-keys "\\[customize-option]")) - (princ " to modify the variables, or put the forms:\n") - (princ " (setq lazy-lock-defer-time ") - (princ (cdr lazy-lock-defer-time)) - (princ ")\n") - (princ " (setq lazy-lock-defer-on-the-fly '") - (princ (car lazy-lock-defer-time)) - (princ ")\n") - (princ "in your ~/.emacs. ") - (princ "The above forms have been evaluated for this editor session,\n") - (princ "but you should use ") - (princ (substitute-command-keys "\\[customize-option]")) - (princ " or change your ~/.emacs now.")) - (setq lazy-lock-defer-on-the-fly (car lazy-lock-defer-time) - lazy-lock-defer-time (cdr lazy-lock-defer-time))) - -(when (boundp 'lazy-lock-defer-driven) - ;; - ;; In 2.06.04 and below, `lazy-lock-defer-driven' was the variable name. - (with-output-to-temp-buffer "*Help*" - (princ "The value of the variable `lazy-lock-defer-driven' is set to ") - (if (memq lazy-lock-defer-driven '(nil t)) - (princ lazy-lock-defer-driven) - (princ "`") - (princ lazy-lock-defer-driven) - (princ "'")) - (princ ".\n") - (princ "This variable is now called `lazy-lock-defer-on-scrolling',\n") - (princ "so instead use ") - (princ (substitute-command-keys "\\[customize-option]")) - (princ " to modify the variable, or put the form:\n") - (princ " (setq lazy-lock-defer-on-scrolling ") - (unless (memq lazy-lock-defer-driven '(nil t)) - (princ "'")) - (princ lazy-lock-defer-driven) - (princ ")\n") - (princ "in your ~/.emacs. ") - (princ "The above form has been evaluated for this editor session,\n") - (princ "but you should use ") - (princ (substitute-command-keys "\\[customize-option]")) - (princ " or change your ~/.emacs now.")) - (setq lazy-lock-defer-on-scrolling lazy-lock-defer-driven)) - -;; Install ourselves: - -(add-hook 'window-size-change-functions #'lazy-lock-fontify-after-resize) -(add-hook 'redisplay-end-trigger-functions #'lazy-lock-fontify-after-trigger) - -(unless (assq 'lazy-lock-mode minor-mode-alist) - (setq minor-mode-alist (append minor-mode-alist '((lazy-lock-mode nil))))) - -(provide 'lazy-lock) - -;; Local Variables: -;; byte-compile-warnings: (not obsolete) -;; End: - -;;; lazy-lock.el ends here |