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1907 lines
84 KiB
EmacsLisp
1907 lines
84 KiB
EmacsLisp
;;; so-long.el --- Say farewell to performance problems with minified code. -*- lexical-binding:t -*-
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;;
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;; Copyright (C) 2015, 2016, 2018, 2019 Free Software Foundation, Inc.
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;; Author: Phil Sainty <psainty@orcon.net.nz>
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;; Maintainer: Phil Sainty <psainty@orcon.net.nz>
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;; URL: https://savannah.nongnu.org/projects/so-long
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;; Keywords: convenience
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;; Created: 23 Dec 2015
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;; Package-Requires: ((emacs "24.4"))
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;; Version: 1.0
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;; This file is part of GNU Emacs.
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;; GNU Emacs is free software: you can redistribute it and/or modify
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;; it under the terms of the GNU General Public License as published by
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;; the Free Software Foundation, either version 3 of the License, or
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;; (at your option) any later version.
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;; GNU Emacs is distributed in the hope that it will be useful,
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;; but WITHOUT ANY WARRANTY; without even the implied warranty of
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;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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;; GNU General Public License for more details.
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;; You should have received a copy of the GNU General Public License
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;; along with GNU Emacs. If not, see <https://www.gnu.org/licenses/>.
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;;; Commentary:
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;;
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;; * Introduction
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;; --------------
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;; When the lines in a file are so long that performance could suffer to an
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;; unacceptable degree, we say "so long" to the slow modes and options enabled
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;; in that buffer, and invoke something much more basic in their place.
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;;
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;; Many Emacs modes struggle with buffers which contain excessively long lines.
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;; This is commonly on account of 'minified' code (i.e. code that has been
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;; compacted into the smallest file size possible, which often entails removing
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;; newlines should they not be strictly necessary). This can result in lines
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;; which are many thousands of characters long, and most programming modes
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;; simply aren't optimised (remotely) for this scenario, so performance can
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;; suffer significantly.
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;;
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;; When such files are detected, the command `so-long' is automatically called,
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;; overriding certain minor modes and variables with performance implications
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;; (all configurable), in order to enhance performance in the buffer.
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;;
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;; The default action enables the major mode `so-long-mode' in place of the mode
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;; that Emacs selected. This ensures that the original major mode cannot affect
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;; performance further, as well as making the so-long activity more obvious to
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;; the user. These kinds of minified files are typically not intended to be
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;; edited, so not providing the usual editing mode in such cases will rarely be
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;; an issue. However, should the user wish to do so, the original state of the
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;; buffer may be reinstated by calling `so-long-revert' (the key binding for
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;; which is advertised when the major mode change occurs). If you prefer that
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;; the major mode not be changed, the `so-long-minor-mode' action can be
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;; configured.
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;;
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;; The user options `so-long-action' and `so-long-action-alist' determine what
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;; will happen when `so-long' and `so-long-revert' are invoked, allowing
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;; alternative actions (including custom actions) to be configured. As well as
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;; the major and minor mode actions provided by this library, `longlines-mode'
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;; is also supported by default as an alternative action.
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;;
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;; Note that while the measures taken can improve performance dramatically when
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;; dealing with such files, this library does not have any effect on the
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;; fundamental limitations of the Emacs redisplay code itself; and so if you do
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;; need to edit the file, performance may still degrade as you get deeper into
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;; the long lines. In such circumstances you may find that `longlines-mode' is
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;; the most helpful facility.
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;;
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;; Note also that the mitigations are automatically triggered when visiting a
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;; file. The library does not automatically detect if long lines are inserted
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;; into an existing buffer (although the `so-long' command can be invoked
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;; manually in such situations).
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;; * Installation
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;; --------------
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;; Use M-x global-so-long-mode to enable/toggle the functionality. To enable
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;; the functionality by default, either customize the `global-so-long-mode' user
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;; option, or add the following to your init file:
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;;
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;; ;; Avoid performance issues in files with very long lines.
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;; (global-so-long-mode 1)
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;;
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;; If necessary, ensure that so-long.el is in a directory in your load-path, and
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;; that the library has been loaded. (These steps are not necessary if you are
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;; using Emacs 27+, or have installed the GNU ELPA package.)
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;; * Overview of modes and commands
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;; --------------------------------
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;; - `global-so-long-mode' - A global minor mode which enables the automated
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;; behaviour, causing the user's preferred action to be invoked whenever a
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;; newly-visited file contains excessively long lines.
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;; - `so-long-mode' - A major mode, and the default action.
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;; - `so-long-minor-mode' - A minor mode version of the major mode, and an
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;; alternative action.
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;; - `longlines-mode' - A minor mode provided by the longlines.el library,
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;; and another alternative action.
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;; - `so-long' - Manually invoke the user's preferred action, enabling its
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;; performance improvements for the current buffer.
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;; - `so-long-revert' - Restore the original state of the buffer.
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;; - `so-long-customize' - Configure the user options.
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;; - `so-long-commentary' - Read this documentation in outline-mode.
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;; * Usage
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;; -------
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;; In most cases you will simply enable `global-so-long-mode' and leave it to
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;; act automatically as required, in accordance with your configuration (see
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;; "Basic configuration" below).
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;;
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;; On rare occasions you may choose to manually invoke the `so-long' command,
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;; which invokes your preferred `so-long-action' (exactly as the automatic
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;; behaviour would do if it had detected long lines). You might use this if a
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;; problematic file did not meet your configured criteria, and you wished to
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;; trigger the performance improvements manually.
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;;
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;; It is also possible to directly use `so-long-mode' or `so-long-minor-mode'
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;; (major and minor modes, respectively). Both of these modes are actions
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;; available to `so-long' but, like any other mode, they can be invoked directly
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;; if you have a need to do that (see also "Other ways of using so-long" below).
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;;
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;; If the behaviour ever triggers when you did not want it to, you can use the
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;; `so-long-revert' command to restore the buffer to its original state.
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;; * Basic configuration
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;; ---------------------
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;; Use M-x customize-group RET so-long RET
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;; (or M-x so-long-customize RET)
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;;
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;; The user options `so-long-target-modes', `so-long-threshold', and
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;; `so-long-max-lines' determine whether action will be taken automatically when
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;; visiting a file, and `so-long-action' determines what will be done.
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;; * Actions and menus
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;; -------------------
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;; The user options `so-long-action' and `so-long-action-alist' determine what
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;; will happen when `so-long' and `so-long-revert' are invoked, and you can add
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;; your own custom actions if you wish. The selected action can be invoked
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;; manually with M-x so-long; and in general M-x so-long-revert will undo the
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;; effects of whichever action was used (which is particularly useful when the
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;; action is triggered automatically, but the detection was a 'false positive'.)
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;;
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;; All defined actions are presented in the "So Long" menu, which is visible
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;; whenever long lines have been detected. Selecting an action from the menu
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;; will firstly cause the current action (if any) to be reverted, before the
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;; newly-selected action is invoked.
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;;
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;; Aside from the menu bar, the menu is also available in the mode line --
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;; either via the major mode construct (when `so-long-mode' is active), or in
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;; a separate mode line construct when some other major mode is active.
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;; * Files with a file-local 'mode'
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;; --------------------------------
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;; A file-local major mode is likely to be safe even if long lines are detected
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;; (as the author of the file would otherwise be unlikely to have set that mode),
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;; and so these files are treated as special cases. When a file-local 'mode' is
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;; present, the function defined by the `so-long-file-local-mode-function' user
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;; option is called. The default value will cause the `so-long-minor-mode'
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;; action to be used instead of the `so-long-mode' action, if the latter was
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;; going to be used for this file. This is still a conservative default, but
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;; this option can also be configured to inhibit so-long entirely in this
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;; scenario, or to not treat a file-local mode as a special case at all.
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;; * Buffers which are not displayed in a window
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;; ---------------------------------------------
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;; When a file with long lines is visited and the buffer is not displayed right
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;; away, it may be that it is not intended to be displayed at all, and that it
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;; has instead been visited for behind-the-scenes processing by some library.
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;; Invisible buffers are less likely to cause performance issues, and it also
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;; might be surprising to the other library if such a buffer were manipulated by
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;; `so-long' (which might in turn lead to confusing errors for the user); so in
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;; these situations the `so-long-invisible-buffer-function' value is called
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;; instead. By default this arranges for `so-long' to be invoked on the buffer
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;; if and when it is displayed, but not otherwise.
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;;
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;; This 'deferred call' is actually the most common scenario -- even when a
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;; visited file is displayed "right away", it is normal for the buffer to be
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;; invisible when `global-so-long-mode' processes it, and the gap between
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;; "arranging to call" and "calling" `so-long' is simply extremely brief.
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;; * Inhibiting and disabling minor modes
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;; --------------------------------------
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;; Certain minor modes cause significant performance issues in the presence of
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;; very long lines, and should be disabled automatically in this situation.
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;;
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;; The simple way to disable most buffer-local minor modes is to add the mode
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;; symbol to the `so-long-minor-modes' list. Several modes are targeted by
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;; default, and it is a good idea to customize this variable to add any
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;; additional buffer-local minor modes that you use which you know to have
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;; performance implications.
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;;
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;; These minor modes are disabled if `so-long-action' is set to either
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;; `so-long-mode' or `so-long-minor-mode'. If `so-long-revert' is called, then
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;; the original values are restored.
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;;
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;; In the case of globalized minor modes, be sure to specify the buffer-local
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;; minor mode, and not the global mode which controls it.
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;;
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;; Note that `so-long-minor-modes' is not useful for other global minor modes
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;; (as distinguished from globalized minor modes), but in some cases it will be
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;; possible to inhibit or otherwise counter-act the behaviour of a global mode
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;; by overriding variables, or by employing hooks (see below). You would need
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;; to inspect the code for a given global mode (on a case by case basis) to
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;; determine whether it's possible to inhibit it for a single buffer -- and if
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;; so, how best to do that, as not all modes are alike.
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;; * Overriding variables
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;; ----------------------
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;; `so-long-variable-overrides' is an alist mapping variable symbols to values.
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;; If `so-long-action' is set to either `so-long-mode' or `so-long-minor-mode',
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;; the buffer-local value for each variable in the list is set to the associated
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;; value in the alist. Use this to enforce values which will improve
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;; performance or otherwise avoid undesirable behaviours. If `so-long-revert'
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;; is called, then the original values are restored.
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;; * Hooks
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;; -------
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;; `so-long-hook' runs at the end of the `so-long' command, after the configured
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;; action has been invoked.
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;;
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;; Likewise, if the `so-long-revert' command is used to restore the original
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;; state then, once that has happened, `so-long-revert-hook' is run.
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;;
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;; The major and minor modes also provide the usual hooks: `so-long-mode-hook'
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;; for the major mode (running between `change-major-mode-after-body-hook' and
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;; `after-change-major-mode-hook'); and `so-long-minor-mode-hook' (when that
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;; mode is enabled or disabled).
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;; * Troubleshooting
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;; -----------------
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;; Any elisp library has the potential to cause performance problems; so while
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;; the default configuration addresses some important common cases, it's
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;; entirely possible that your own config introduces problem cases which are
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;; unknown to this library.
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;;
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;; If visiting a file is still taking a very long time with so-long enabled,
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;; you should test the following command:
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;;
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;; emacs -Q -l so-long -f global-so-long-mode <file>
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;;
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;; For versions of Emacs < 27, use:
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;; emacs -Q -l /path/to/so-long.el -f global-so-long-mode <file>
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;;
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;; If the file loads quickly when that command is used, you'll know that
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;; something in your personal configuration is causing problems. If this
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;; turns out to be a buffer-local minor mode, or a user option, you can
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;; likely alleviate the issue by customizing `so-long-minor-modes' or
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;; `so-long-variable-overrides' accordingly.
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;;
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;; The in-built profiler can be an effective way of discovering the cause
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;; of such problems. Refer to M-: (info "(elisp) Profiling") RET
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;;
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;; In some cases it may be useful to set a file-local `mode' variable to
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;; `so-long-mode', completely bypassing the automated decision process.
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;; Refer to M-: (info "(emacs) Specifying File Variables") RET
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;;
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;; If so-long itself is causing problems, it can be inhibited by setting the
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;; `so-long-enabled' variable to nil, or by disabling the global mode with
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;; M-- M-x global-so-long-mode, or M-: (global-so-long-mode 0)
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;; * Example configuration
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;; -----------------------
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;; If you prefer to configure in code rather than via the customize interface,
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;; then you might use something along these lines:
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;;
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;; ;; Enable so-long library.
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;; (when (require 'so-long nil :noerror)
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;; (global-so-long-mode 1)
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;; ;; Basic settings.
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;; (setq so-long-action 'so-long-minor-mode)
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;; (setq so-long-threshold 1000)
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;; (setq so-long-max-lines 100)
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;; ;; Additional target major modes to trigger for.
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;; (mapc (apply-partially 'add-to-list 'so-long-target-modes)
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;; '(sgml-mode nxml-mode))
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;; ;; Additional buffer-local minor modes to disable.
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;; (mapc (apply-partially 'add-to-list 'so-long-minor-modes)
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;; '(diff-hl-mode diff-hl-amend-mode diff-hl-flydiff-mode))
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;; ;; Additional variables to override.
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;; (mapc (apply-partially 'add-to-list 'so-long-variable-overrides)
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;; '((show-trailing-whitespace . nil)
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;; (truncate-lines . nil))))
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;; * Other ways of using so-long
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;; -----------------------------
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;; It may prove useful to automatically invoke major mode `so-long-mode' for
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;; certain files, irrespective of whether they contain long lines.
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;;
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;; To target specific files and extensions, using `auto-mode-alist' is the
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;; simplest method. To add such an entry, use:
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;; (add-to-list 'auto-mode-alist (cons REGEXP 'so-long-mode))
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;; Where REGEXP is a regular expression matching the filename. e.g.:
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;;
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;; - Any filename with a particular extension ".foo":
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;; (rx ".foo" eos)
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;;
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;; - Any file in a specific directory:
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;; (rx bos "/path/to/directory/")
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;;
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;; - Only *.c filenames under that directory:
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;; (rx bos "/path/to/directory/" (zero-or-more not-newline) ".c" eos)
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;;
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;; - Match some sub-path anywhere in a filename:
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;; (rx "/sub/path/foo")
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;;
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;; - A specific individual file:
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;; (rx bos "/path/to/file" eos)
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;;
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;; Another way to target individual files is to set a file-local `mode'
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;; variable. Refer to M-: (info "(emacs) Specifying File Variables") RET
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;;
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;; `so-long-minor-mode' can also be called directly if desired. e.g.:
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;; (add-hook 'FOO-mode-hook 'so-long-minor-mode)
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;;
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;; In Emacs 26.1 or later (see "Caveats" below) you also have the option of
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;; using file-local and directory-local variables to determine how `so-long'
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;; behaves. e.g. -*- so-long-action: longlines-mode; -*-
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;;
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;; The buffer-local `so-long-function' and `so-long-revert-function' values may
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;; be set directly (in a major mode hook, for instance), as any existing value
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;; for these variables will be used in preference to the values defined by the
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;; selected action. For file-local or directory-local usage it is preferable to
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;; set only `so-long-action', as all function variables are marked as 'risky',
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;; meaning you would need to add to `safe-local-variable-values' in order to
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;; avoid being queried about them.
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;;
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;; Finally, the `so-long-predicate' user option enables the automated behaviour
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;; to be determined by a custom function, if greater control is needed.
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;; * Implementation notes
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;; ----------------------
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;; This library advises `set-auto-mode' (in order to react after Emacs has
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;; chosen the major mode for a buffer), and `hack-local-variables' (so that we
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;; may behave differently when a file-local mode is set). In earlier versions
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;; of Emacs (< 26.1) we also advise `hack-one-local-variable' (to prevent a
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;; file-local mode from restoring the original major mode if we had changed it).
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;;
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;; Many variables are permanent-local because after the normal major mode has
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;; been set, we potentially change the major mode to `so-long-mode', and it's
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;; important that the values which were established prior to that are retained.
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;; * Caveats
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;; ---------
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;; The variables affecting the automated behaviour of this library (such as
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;; `so-long-action') can be used as file- or dir-local values in Emacs 26+, but
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;; not in previous versions of Emacs. This is on account of improvements made
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;; to `normal-mode' in 26.1, which altered the execution order with respect to
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;; when local variables are processed. In earlier versions of Emacs the local
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;; variables are processed too late, and hence have no effect on the decision-
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;; making process for invoking `so-long'. It is unlikely that equivalent
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;; support will be implemented for older versions of Emacs. The exception to
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;; this caveat is the `mode' pseudo-variable, which is processed early in all
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;; versions of Emacs, and can be set to `so-long-mode' if desired.
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;;; * Change Log:
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;;
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;; 1.0 - Included in Emacs 27.1, and in GNU ELPA for prior versions of Emacs.
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;; - New global mode `global-so-long-mode' to enable/disable the library.
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;; - New user option `so-long-action'.
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;; - New user option `so-long-action-alist' defining alternative actions.
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;; - New user option `so-long-variable-overrides'.
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;; - New user option `so-long-skip-leading-comments'.
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;; - New user option `so-long-file-local-mode-function'.
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;; - New user option `so-long-invisible-buffer-function'.
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;; - New user option `so-long-predicate'.
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;; - New variable and function `so-long-function'.
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;; - New variable and function `so-long-revert-function'.
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;; - New command `so-long' to invoke `so-long-function' interactively.
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||
;; - New command `so-long-revert' to invoke `so-long-revert-function'.
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||
;; - New minor mode action `so-long-minor-mode' facilitates retaining the
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;; original major mode, while still disabling minor modes and overriding
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;; variables like the major mode `so-long-mode'.
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;; - Support `longlines-mode' as a `so-long-action' option.
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;; - Added "So Long" menu, including all selectable actions.
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;; - Added mode-line indicator, user option `so-long-mode-line-label',
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;; and faces `so-long-mode-line-active', `so-long-mode-line-inactive'.
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;; - New help commands `so-long-commentary' and `so-long-customize'.
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;; - Renamed `so-long-mode-enabled' to `so-long-enabled'.
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;; - Refactored the default hook values using variable overrides
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;; (and returning all the hooks to nil default values).
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||
;; - Performance improvements for `so-long-detected-long-line-p'.
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||
;; - Converted defadvice to nadvice.
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||
;; 0.7.6 - Bug fix for `so-long-mode-hook' losing its default value.
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;; 0.7.5 - Documentation.
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;; - Added sgml-mode and nxml-mode to `so-long-target-modes'.
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;; 0.7.4 - Refactored the handling of `whitespace-mode'.
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;; 0.7.3 - Added customize group `so-long' with user options.
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;; - Added `so-long-original-values' to generalise the storage and
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||
;; restoration of values from the original mode upon `so-long-revert'.
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;; - Added `so-long-revert-hook'.
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;; 0.7.2 - Remember the original major mode even with M-x `so-long-mode'.
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;; 0.7.1 - Clarified interaction with globalized minor modes.
|
||
;; 0.7 - Handle header 'mode' declarations.
|
||
;; - Hack local variables after reverting to the original major mode.
|
||
;; - Reverted `so-long-max-lines' to a default value of 5.
|
||
;; 0.6.5 - Inhibit globalized `hl-line-mode' and `whitespace-mode'.
|
||
;; - Set `buffer-read-only' by default.
|
||
;; 0.6 - Added `so-long-minor-modes' and `so-long-hook'.
|
||
;; 0.5 - Renamed library to "so-long.el".
|
||
;; - Added explicit `so-long-enable' command to activate our advice.
|
||
;; 0.4 - Amended/documented behaviour with file-local 'mode' variables.
|
||
;; 0.3 - Defer to a file-local 'mode' variable.
|
||
;; 0.2 - Initial release to EmacsWiki.
|
||
;; 0.1 - Experimental.
|
||
|
||
;;; Code:
|
||
|
||
(require 'cl-lib)
|
||
|
||
(add-to-list 'customize-package-emacs-version-alist
|
||
'(so-long ("1.0" . "27.1")))
|
||
|
||
(defconst so-long--latest-version "1.0")
|
||
|
||
(declare-function longlines-mode "longlines")
|
||
(defvar longlines-mode)
|
||
|
||
(declare-function outline-next-visible-heading "outline")
|
||
(declare-function outline-previous-visible-heading "outline")
|
||
(declare-function outline-toggle-children "outline")
|
||
(declare-function outline-toggle-children "outline")
|
||
|
||
(defvar so-long-enabled nil
|
||
"Set to nil to prevent `so-long' from being triggered automatically.
|
||
|
||
Has no effect if `global-so-long-mode' is not enabled.")
|
||
|
||
(defvar-local so-long--active nil ; internal use
|
||
"Non-nil when `so-long' mitigations are in effect.")
|
||
|
||
(defvar so-long--set-auto-mode nil ; internal use
|
||
"Non-nil while `set-auto-mode' is executing.")
|
||
|
||
(defvar so-long--hack-local-variables-no-mode nil ; internal use
|
||
"Non-nil to prevent `hack-local-variables' applying a `mode' variable.")
|
||
|
||
(defvar-local so-long--inhibited nil ; internal use
|
||
"When non-nil, prevents the `set-auto-mode' advice from calling `so-long'.")
|
||
(put 'so-long--inhibited 'permanent-local t)
|
||
|
||
(defvar so-long--calling nil ; internal use
|
||
;; This prevents infinite recursion if eval:(so-long) is specified
|
||
;; as a file- or dir-local variable, and `so-long-action' is set to
|
||
;; `so-long-mode' (as that major mode would once again process the
|
||
;; local variables, and hence call itself).
|
||
"Non-nil while `so-long' or `so-long-revert' is executing.")
|
||
|
||
(defvar-local so-long-detected-p nil
|
||
"Non-nil if `so-long' has been invoked (even if subsequently reverted).")
|
||
(put 'so-long-detected-p 'permanent-local t)
|
||
|
||
(defgroup so-long nil
|
||
"Prevent unacceptable performance degradation with very long lines."
|
||
:prefix "so-long"
|
||
:group 'convenience)
|
||
|
||
(defcustom so-long-threshold 250
|
||
"Maximum line length permitted before invoking `so-long-function'.
|
||
|
||
See `so-long-detected-long-line-p' for details."
|
||
:type 'integer
|
||
:package-version '(so-long . "1.0")
|
||
:group 'so-long)
|
||
|
||
(defcustom so-long-max-lines 5
|
||
"Number of non-blank, non-comment lines to test for excessive length.
|
||
|
||
If nil then all lines will be tested, until either a long line is detected,
|
||
or the end of the buffer is reached.
|
||
|
||
If `so-long-skip-leading-comments' is nil then comments and blank lines will
|
||
be counted.
|
||
|
||
See `so-long-detected-long-line-p' for details."
|
||
:type '(choice (integer :tag "Limit")
|
||
(const :tag "Unlimited" nil))
|
||
:package-version '(so-long . "1.0")
|
||
:group 'so-long)
|
||
|
||
(defcustom so-long-skip-leading-comments t
|
||
"Non-nil to ignore all leading comments and whitespace.
|
||
|
||
If the file begins with a shebang (#!), this option also causes that line to be
|
||
ignored even if it doesn't match the buffer's comment syntax, to ensure that
|
||
comments following the shebang will be ignored.
|
||
|
||
See `so-long-detected-long-line-p' for details."
|
||
:type 'boolean
|
||
:package-version '(so-long . "1.0")
|
||
:group 'so-long)
|
||
|
||
(defcustom so-long-target-modes
|
||
'(prog-mode css-mode sgml-mode nxml-mode)
|
||
"`so-long' affects only these modes and their derivatives.
|
||
|
||
Our primary use-case is minified programming code, so `prog-mode' covers
|
||
most cases, but there are some exceptions to this.
|
||
|
||
If t, then all modes are targeted. Note that this is only useful with a
|
||
custom `so-long-predicate', as many file types (archives and binary files,
|
||
for example) can safely contain long lines, and invoking `so-long' on such
|
||
files would prevent Emacs from handling them correctly."
|
||
;; Use 'symbol', as 'function' may be unknown => mismatch.
|
||
:type '(choice (repeat :tag "Specified modes" symbol)
|
||
(const :tag "All modes" t))
|
||
:package-version '(so-long . "1.0")
|
||
:group 'so-long)
|
||
|
||
(defcustom so-long-invisible-buffer-function #'so-long-deferred
|
||
"Function called in place of `so-long' when the buffer is not displayed.
|
||
|
||
This affects the behaviour of `global-so-long-mode'.
|
||
|
||
We treat invisible buffers differently from displayed buffers because, in
|
||
cases where a library is using a buffer for behind-the-scenes processing,
|
||
it might be surprising if that buffer were unexpectedly manipulated by
|
||
`so-long' (which might in turn lead to confusing errors for the user).
|
||
Invisible buffers are less likely to cause performance issues related to
|
||
long lines, so this differentiation is generally satisfactory.
|
||
|
||
The default value `so-long-deferred' prevents `global-so-long-mode' from
|
||
triggering `so-long' for any given buffer until such time as the buffer is
|
||
displayed in a window.
|
||
|
||
\(Note that buffers are normally invisible at this point -- when `find-file'
|
||
is used, the buffer is not displayed in a window until a short time after
|
||
`global-so-long-mode' has seen it.)
|
||
|
||
The value nil or `so-long' means that `so-long' will be called directly; in
|
||
which case it may be problematic for `so-long-variable-overrides' to enable
|
||
`buffer-read-only', or for `so-long-action' to be set to `so-long-mode'.
|
||
This is because the buffer may not be intended to be displayed at all, and
|
||
the mentioned options might interfere with some intended processing."
|
||
:type '(radio (const so-long-deferred)
|
||
(const :tag "nil: Call so-long as normal" nil)
|
||
(function :tag "Custom function"))
|
||
:package-version '(so-long . "1.0")
|
||
:group 'so-long)
|
||
|
||
(defcustom so-long-predicate 'so-long-detected-long-line-p
|
||
"Function, called after `set-auto-mode' to decide whether action is needed.
|
||
|
||
Only called if the major mode is a member of `so-long-target-modes'.
|
||
|
||
The specified function will be called with no arguments. If it returns non-nil
|
||
then `so-long' will be invoked.
|
||
|
||
Defaults to `so-long-detected-long-line-p'."
|
||
:type '(radio (const so-long-detected-long-line-p)
|
||
(function :tag "Custom function"))
|
||
:package-version '(so-long . "1.0")
|
||
:group 'so-long)
|
||
|
||
;; Silence byte-compiler warning. `so-long-action-alist' is defined below
|
||
;; as a user option; but the definition sequence required for its setter
|
||
;; function means we also need to declare it beforehand.
|
||
(defvar so-long-action-alist)
|
||
|
||
(defun so-long--action-type ()
|
||
"Generate a :type for `so-long-action' based on `so-long-action-alist'."
|
||
;; :type seemingly cannot be a form to be evaluated on demand, so we
|
||
;; endeavour to keep it up-to-date with `so-long-action-alist' by
|
||
;; calling this from `so-long--action-alist-setter'.
|
||
`(radio ,@(mapcar (lambda (x) (list 'const :tag (cadr x) (car x)))
|
||
(assq-delete-all nil so-long-action-alist))
|
||
(const :tag "Do nothing" nil)))
|
||
|
||
(defun so-long--action-alist-setter (option value)
|
||
"The customize :set function for `so-long-action-alist'."
|
||
;; Set the value as normal.
|
||
(set-default option value)
|
||
;; Update the :type of `so-long-action' to present the updated values.
|
||
(put 'so-long-action 'custom-type (so-long--action-type)))
|
||
|
||
(defcustom so-long-action-alist
|
||
'((so-long-mode
|
||
"Change major mode to so-long-mode"
|
||
so-long-mode
|
||
so-long-mode-revert)
|
||
(so-long-minor-mode
|
||
"Enable so-long-minor-mode"
|
||
turn-on-so-long-minor-mode
|
||
turn-off-so-long-minor-mode)
|
||
(longlines-mode
|
||
"Enable longlines-mode"
|
||
so-long-function-longlines-mode
|
||
so-long-revert-function-longlines-mode))
|
||
"Options for `so-long-action'.
|
||
|
||
Each element is a list comprising (KEY LABEL ACTION REVERT)
|
||
|
||
KEY is a symbol which is a valid value for `so-long-action', and LABEL is a
|
||
string which describes and represents the key in that option's customize
|
||
interface, and in the \"So Long\" menu. ACTION and REVERT are functions:
|
||
|
||
ACTION will be the `so-long-function' value when `so-long' is called, and
|
||
REVERT will be the `so-long-revert-function' value, if `so-long-revert' is
|
||
subsequently called."
|
||
:type '(alist :key-type (symbol :tag "Key" :value <action>)
|
||
:value-type (list (string :tag "Label" :value "<description>")
|
||
(function :tag "Action")
|
||
(function :tag "Revert")))
|
||
:set #'so-long--action-alist-setter
|
||
:package-version '(so-long . "1.0")
|
||
:group 'so-long)
|
||
(put 'so-long-action-alist 'risky-local-variable t)
|
||
|
||
(defcustom so-long-action 'so-long-mode
|
||
"The action taken by `so-long' when long lines are detected.
|
||
|
||
\(Long lines are determined by `so-long-predicate' after `set-auto-mode'.)
|
||
|
||
The value is a key to one of the options defined by `so-long-action-alist'.
|
||
|
||
The default action is to replace the original major mode with `so-long-mode'.
|
||
Alternatively, the `so-long-minor-mode' action retains the original major mode
|
||
while still disabling minor modes and overriding variables. These are the only
|
||
standard values for which `so-long-minor-modes' and `so-long-variable-overrides'
|
||
will be automatically processed; but custom actions can also do these things.
|
||
|
||
The value `longlines-mode' causes that minor mode to be enabled. See
|
||
longlines.el for more details.
|
||
|
||
Each action likewise determines the behaviour of `so-long-revert'.
|
||
|
||
If the value is nil, or not defined in `so-long-action-alist', then no action
|
||
will be taken."
|
||
:type (so-long--action-type)
|
||
:package-version '(so-long . "1.0")
|
||
:group 'so-long)
|
||
|
||
(defvar-local so-long-function nil
|
||
"The function called by `so-long'.
|
||
|
||
This should be set in conjunction with `so-long-revert-function'. This usually
|
||
happens automatically, based on the value of `so-long-action'.
|
||
|
||
The specified function will be called with no arguments, after which
|
||
`so-long-hook' runs.")
|
||
(put 'so-long-function 'permanent-local t)
|
||
|
||
(defvar-local so-long-revert-function nil
|
||
"The function called by `so-long-revert'.
|
||
|
||
This should be set in conjunction with `so-long-function'. This usually
|
||
happens automatically, based on the value of `so-long-action'.
|
||
|
||
The specified function will be called with no arguments, after which
|
||
`so-long-revert-hook' runs.")
|
||
(put 'so-long-revert-function 'permanent-local t)
|
||
|
||
(defun so-long-function (&optional action-arg)
|
||
"The value of `so-long-function', else derive from `so-long-action'.
|
||
|
||
If ACTION-ARG is provided, it is used in place of `so-long-action'."
|
||
(or so-long-function
|
||
(and (or action-arg
|
||
(setq action-arg so-long-action))
|
||
(let ((action (assq action-arg so-long-action-alist)))
|
||
(nth 2 action)))))
|
||
|
||
(defun so-long-revert-function (&optional action-arg)
|
||
"The value of `so-long-revert-function', else derive from `so-long-action'.
|
||
|
||
If ACTION-ARG is provided, it is used in place of `so-long-action'."
|
||
(or so-long-revert-function
|
||
(and (or action-arg
|
||
(setq action-arg so-long-action))
|
||
(let ((action (assq action-arg so-long-action-alist)))
|
||
(nth 3 action)))))
|
||
|
||
(defcustom so-long-file-local-mode-function 'so-long-mode-downgrade
|
||
"Function to call during `set-auto-mode' when a file-local mode is set.
|
||
|
||
The specified function will be called with a single argument, being the
|
||
file-local mode which was established.
|
||
|
||
This happens before `so-long' is called, and so this function can modify the
|
||
subsequent action.
|
||
|
||
The value `so-long-mode-downgrade' means `so-long-minor-mode' will be used in
|
||
place of `so-long-mode' -- therefore respecting the file-local mode value, yet
|
||
still overriding minor modes and variables (as if `so-long-action' had been set
|
||
to `so-long-minor-mode').
|
||
|
||
The value `so-long-inhibit' means that so-long will not take any action at all
|
||
for this file.
|
||
|
||
If nil, then do not treat files with file-local modes any differently to other
|
||
files.
|
||
|
||
Note that this function is called if a file-local mode is set even if `so-long'
|
||
will not be called, and also if the file-local mode is `so-long-mode'. Custom
|
||
functions may need to test for these cases -- see `so-long-mode-downgrade' for
|
||
an example."
|
||
:type '(radio (const so-long-mode-downgrade)
|
||
(const so-long-inhibit)
|
||
(const :tag "nil: Use so-long-function as normal" nil)
|
||
(function :tag "Custom function"))
|
||
:package-version '(so-long . "1.0")
|
||
:group 'so-long)
|
||
(make-variable-buffer-local 'so-long-file-local-mode-function)
|
||
|
||
;; `provided-mode-derived-p' was added in 26.1
|
||
(unless (fboundp 'provided-mode-derived-p)
|
||
(defun provided-mode-derived-p (mode &rest modes)
|
||
"Non-nil if MODE is derived from one of MODES.
|
||
Uses the `derived-mode-parent' property of the symbol to trace backwards.
|
||
If you just want to check `major-mode', use `derived-mode-p'."
|
||
(while (and (not (memq mode modes))
|
||
(setq mode (get mode 'derived-mode-parent))))
|
||
mode))
|
||
|
||
(defun so-long-handle-file-local-mode (mode)
|
||
"Wrapper for calling `so-long-file-local-mode-function'.
|
||
|
||
The function is called with one argument, MODE, being the file-local mode which
|
||
was established."
|
||
;; Handle the special case whereby the file-local mode was `so-long-mode'.
|
||
;; In this instance we set `so-long--inhibited', because the file-local mode
|
||
;; is already going to do everything that is wanted.
|
||
(when (provided-mode-derived-p mode 'so-long-mode)
|
||
(setq so-long--inhibited t))
|
||
;; Call `so-long-file-local-mode-function'.
|
||
(when so-long-file-local-mode-function
|
||
(funcall so-long-file-local-mode-function mode)))
|
||
|
||
(defcustom so-long-minor-modes
|
||
;; In sorted groups.
|
||
'(font-lock-mode ;; (Generally the most important).
|
||
;; Other standard minor modes:
|
||
display-line-numbers-mode
|
||
flymake-mode
|
||
flyspell-mode
|
||
goto-address-mode
|
||
goto-address-prog-mode
|
||
hi-lock-mode
|
||
highlight-changes-mode
|
||
hl-line-mode
|
||
linum-mode
|
||
nlinum-mode
|
||
prettify-symbols-mode
|
||
visual-line-mode
|
||
whitespace-mode
|
||
;; Known third-party modes-of-interest:
|
||
diff-hl-amend-mode
|
||
diff-hl-flydiff-mode
|
||
diff-hl-mode
|
||
dtrt-indent-mode
|
||
flycheck-mode
|
||
hl-sexp-mode
|
||
idle-highlight-mode
|
||
rainbow-delimiters-mode
|
||
)
|
||
;; It's not clear to me whether all of these would be problematic, but they
|
||
;; seemed like reasonable targets. Some are certainly excessive in smaller
|
||
;; buffers of minified code, but we should be aiming to maximise performance
|
||
;; by default, so that Emacs is as responsive as we can manage in even very
|
||
;; large buffers of minified code.
|
||
"List of buffer-local minor modes to explicitly disable.
|
||
|
||
The ones which were originally enabled in the buffer are disabled by calling
|
||
them with the numeric argument 0. Unknown modes, and modes which were not
|
||
enabled, are ignored.
|
||
|
||
This happens after any globalized minor modes have acted, so that buffer-local
|
||
modes controlled by globalized modes can also be targeted.
|
||
|
||
By default this happens if `so-long-action' is set to either `so-long-mode'
|
||
or `so-long-minor-mode'. If `so-long-revert' is subsequently invoked, then the
|
||
disabled modes are re-enabled by calling them with the numeric argument 1.
|
||
|
||
`so-long-hook' can be used where more custom behaviour is desired.
|
||
|
||
Please submit bug reports to recommend additional modes for this list, whether
|
||
they are in Emacs core, GNU ELPA, or elsewhere."
|
||
:type '(repeat symbol) ;; not function, as may be unknown => mismatch.
|
||
:package-version '(so-long . "1.0")
|
||
:group 'so-long)
|
||
|
||
(defcustom so-long-variable-overrides
|
||
'((bidi-paragraph-direction . left-to-right)
|
||
(buffer-read-only . t)
|
||
(global-hl-line-mode . nil)
|
||
(line-move-visual . t)
|
||
(show-paren-mode . nil)
|
||
(truncate-lines . nil)
|
||
(which-func-mode . nil))
|
||
"Variables to override, and the values to override them with.
|
||
|
||
The variables are given buffer-local values. By default this happens if
|
||
`so-long-action' is set to either `so-long-mode' or `so-long-minor-mode'.
|
||
|
||
If `so-long-revert' is subsequently invoked, then the variables are restored
|
||
to their original states.
|
||
|
||
The combination of `line-move-visual' (enabled) and `truncate-lines' (disabled)
|
||
is important for maximising responsiveness when moving vertically within an
|
||
extremely long line, as otherwise the full length of the line may need to be
|
||
scanned to find the next position."
|
||
:type '(alist :key-type (variable :tag "Variable")
|
||
:value-type (sexp :tag "Value"))
|
||
:options '((bidi-paragraph-direction (choice (const left-to-right)
|
||
(const right-to-left)
|
||
(const nil)))
|
||
(buffer-read-only boolean)
|
||
(global-hl-line-mode boolean)
|
||
(line-move-visual boolean)
|
||
(show-paren-mode boolean)
|
||
(truncate-lines boolean)
|
||
(which-func-mode boolean))
|
||
:package-version '(so-long . "1.0")
|
||
:group 'so-long)
|
||
|
||
(defcustom so-long-hook nil
|
||
"List of functions to call after `so-long' is called.
|
||
|
||
See also `so-long-revert-hook'."
|
||
:type 'hook
|
||
:package-version '(so-long . "1.0")
|
||
:group 'so-long)
|
||
|
||
(defcustom so-long-revert-hook nil
|
||
"List of functions to call after `so-long-revert' is called.
|
||
|
||
See also `so-long-hook'."
|
||
:type 'hook
|
||
:package-version '(so-long . "1.0")
|
||
:group 'so-long)
|
||
|
||
(defcustom so-long-mode-line-label "So Long"
|
||
"Text label of `so-long-mode-line-info' when long lines are detected.
|
||
|
||
If nil, no mode line indicator will be displayed."
|
||
:type '(choice (string :tag "String")
|
||
(const :tag "None" nil))
|
||
:package-version '(so-long . "1.0")
|
||
:group 'so-long)
|
||
|
||
(defface so-long-mode-line-active
|
||
'((t :inherit mode-line-emphasis))
|
||
"Face for `so-long-mode-line-info' when mitigations are active."
|
||
:package-version '(so-long . "1.0")
|
||
:group 'so-long)
|
||
|
||
(defface so-long-mode-line-inactive
|
||
'((t :inherit mode-line-inactive))
|
||
"Face for `so-long-mode-line-info' when mitigations have been reverted."
|
||
:package-version '(so-long . "1.0")
|
||
:group 'so-long)
|
||
|
||
;; Modes that go slowly and line lengths excessive
|
||
;; Font-lock performance becoming oppressive
|
||
;; All of my CPU tied up with strings
|
||
;; These are a few of my least-favourite things
|
||
|
||
(defvar-local so-long-original-values nil
|
||
"Alist holding the buffer's original `major-mode' value, and other data.
|
||
|
||
Any values to be restored by `so-long-revert' can be stored here by the
|
||
`so-long-function' or during `so-long-hook'. `so-long' itself stores the
|
||
original states for `so-long-variable-overrides' and `so-long-minor-modes',
|
||
so these values are available to custom actions by default.
|
||
|
||
See also `so-long-remember' and `so-long-original'.")
|
||
(put 'so-long-original-values 'permanent-local t)
|
||
|
||
(defun so-long-original (key &optional exists)
|
||
"Return the current value for KEY in `so-long-original-values'.
|
||
|
||
If you need to differentiate between a stored value of nil and no stored value
|
||
at all, make EXISTS non-nil. This then returns the result of `assq' directly:
|
||
nil if no value was set, and a cons cell otherwise."
|
||
(if exists
|
||
(assq key so-long-original-values)
|
||
(cadr (assq key so-long-original-values))))
|
||
|
||
(defun so-long-remember (variable)
|
||
"Store the value of VARIABLE in `so-long-original-values'.
|
||
|
||
We additionally store a boolean value which indicates whether that value was
|
||
buffer-local."
|
||
(when (boundp variable)
|
||
(setq so-long-original-values
|
||
(assq-delete-all variable so-long-original-values))
|
||
(push (list variable
|
||
(symbol-value variable)
|
||
(local-variable-p variable))
|
||
so-long-original-values)))
|
||
|
||
(defun so-long-remember-all (&optional reset)
|
||
"Remember the current variable and minor mode values.
|
||
|
||
Stores the existing value for each entry in `so-long-variable-overrides'.
|
||
Stores the name of each enabled mode from the list `so-long-minor-modes'.
|
||
|
||
If RESET is non-nil, remove any existing values before storing the new ones."
|
||
(when reset
|
||
(setq so-long-original-values nil))
|
||
(dolist (ovar so-long-variable-overrides)
|
||
(so-long-remember (car ovar)))
|
||
(dolist (mode so-long-minor-modes)
|
||
(when (and (boundp mode) mode)
|
||
(so-long-remember mode))))
|
||
|
||
(defun so-long-menu ()
|
||
"Dynamically generate the \"So Long\" menu."
|
||
;; (info "(elisp) Menu Example")
|
||
(let ((map (make-sparse-keymap "So Long"))
|
||
(help-map (make-sparse-keymap "Help")))
|
||
;; `so-long-revert'.
|
||
(define-key-after map [so-long-revert]
|
||
'(menu-item "Revert to normal" so-long-menu-item-revert
|
||
:enable (and so-long-revert-function
|
||
so-long--active)))
|
||
;; `so-long-menu-item-replace-action' over `so-long-action-alist'.
|
||
(define-key-after map [so-long-actions-separator]
|
||
'(menu-item "--"))
|
||
(dolist (item so-long-action-alist)
|
||
(cl-destructuring-bind (key label actionfunc revertfunc)
|
||
item
|
||
(define-key-after map (vector key)
|
||
`(menu-item
|
||
,label
|
||
,(let ((sym (make-symbol "so-long-menu-item-replace-action")))
|
||
;; Using a symbol here, so that `describe-key' on the menu item
|
||
;; produces the `so-long-menu-item-replace-action' documentation.
|
||
(defalias sym
|
||
(apply-partially #'so-long-menu-item-replace-action item)
|
||
(documentation #'so-long-menu-item-replace-action))
|
||
(put sym 'interactive-form '(interactive))
|
||
sym)
|
||
:enable (not (and so-long--active
|
||
(eq ',actionfunc so-long-function)
|
||
(eq ',revertfunc so-long-revert-function)))))))
|
||
;; "Help" sub-menu.
|
||
(define-key-after map [so-long-help-separator]
|
||
'(menu-item "--"))
|
||
(define-key-after map [so-long-help]
|
||
`(menu-item "Help" ,help-map))
|
||
(define-key-after help-map [so-long-commentary]
|
||
'(menu-item "Commentary" so-long-commentary))
|
||
(define-key-after help-map [so-long-customize]
|
||
'(menu-item "Customize" so-long-customize))
|
||
map))
|
||
|
||
(defun so-long-menu-click-window ()
|
||
"Return the window for a click in the So Long menu.
|
||
|
||
Commands in the mode-line menu may be triggered by mouse when some other window
|
||
is selected, so we need to make sure we are acting on the correct buffer."
|
||
;; Refer to (info "(elisp) Click Events") regarding the form of the mouse
|
||
;; position list for clicks in the mode line.
|
||
(or (and (mouse-event-p last-nonmenu-event)
|
||
(windowp (car (cadr last-nonmenu-event))) ; cXXXr only available
|
||
(car (cadr last-nonmenu-event))) ; since Emacs 26.1
|
||
(selected-window)))
|
||
|
||
(defun so-long-menu-item-revert ()
|
||
"Invoke `so-long-revert'."
|
||
(interactive)
|
||
(with-selected-window (so-long-menu-click-window)
|
||
(so-long-revert)))
|
||
|
||
(defun so-long-menu-item-replace-action (replacement)
|
||
"Revert the current action and invoke the specified replacement.
|
||
|
||
REPLACEMENT is a `so-long-action-alist' item."
|
||
(interactive)
|
||
(with-selected-window (so-long-menu-click-window)
|
||
(when so-long--active
|
||
(so-long-revert))
|
||
(cl-destructuring-bind (_key _label actionfunc revertfunc)
|
||
replacement
|
||
(setq so-long-function actionfunc)
|
||
(setq so-long-revert-function revertfunc)
|
||
(setq this-command 'so-long)
|
||
(so-long))))
|
||
|
||
;;;###autoload
|
||
(defun so-long-commentary ()
|
||
"View the so-long documentation in `outline-mode'."
|
||
(interactive)
|
||
(let ((buf "*So Long: Commentary*"))
|
||
(when (buffer-live-p (get-buffer buf))
|
||
(kill-buffer buf))
|
||
;; Use `finder-commentary' to generate the buffer.
|
||
(require 'finder)
|
||
(cl-letf (((symbol-function 'finder-summary) #'ignore))
|
||
(finder-commentary "so-long"))
|
||
(let ((inhibit-read-only t))
|
||
(when (looking-at "^Commentary:\n\n")
|
||
(replace-match "so-long.el\n\n"))
|
||
(save-excursion
|
||
(while (re-search-forward "^-+$" nil :noerror)
|
||
(replace-match ""))))
|
||
(rename-buffer buf)
|
||
;; Enable `outline-mode' and `view-mode' for user convenience.
|
||
(outline-mode)
|
||
(view-mode 1)
|
||
;; Add some custom local bindings.
|
||
(let ((map (make-sparse-keymap)))
|
||
(define-key map (kbd "TAB") #'outline-toggle-children)
|
||
(define-key map (kbd "<M-tab>") #'outline-toggle-children)
|
||
(define-key map (kbd "M-n") #'outline-next-visible-heading)
|
||
(define-key map (kbd "M-p") #'outline-previous-visible-heading)
|
||
(set-keymap-parent map (current-local-map))
|
||
(use-local-map map))
|
||
;; Display the So Long menu.
|
||
(so-long--ensure-enabled)
|
||
(let ((so-long-action nil))
|
||
(so-long))))
|
||
|
||
;;;###autoload
|
||
(defun so-long-customize ()
|
||
"Open the so-long `customize' group."
|
||
(interactive)
|
||
(customize-group 'so-long))
|
||
|
||
(defvar-local so-long-mode-line-info nil
|
||
"Mode line construct displayed when `so-long' has been triggered.
|
||
|
||
Displayed as part of `mode-line-misc-info'.
|
||
|
||
`so-long-mode-line-label' defines the text to be displayed (if any).
|
||
|
||
Face `so-long-mode-line-active' is used while mitigations are active, and
|
||
`so-long-mode-line-inactive' is used if `so-long-revert' is called.
|
||
|
||
Not displayed when `so-long-mode' is enabled, as the major mode construct
|
||
serves the same purpose.")
|
||
|
||
;; Ensure we can display text properties on this value in the mode line.
|
||
;; See (info "(elisp) Mode Line Data") or (info "(elisp) Properties in Mode").
|
||
(put 'so-long-mode-line-info 'risky-local-variable t)
|
||
|
||
(defun so-long-mode-line-info ()
|
||
"Return the mode line construct for variable `so-long-mode-line-info'."
|
||
(let ((map (make-sparse-keymap)))
|
||
(define-key map (kbd "<mode-line> <down-mouse-1>")
|
||
`(menu-item "" nil
|
||
:filter ,(lambda (_cmd) (so-long-menu))))
|
||
;; Mode line construct.
|
||
;; n.b. It's necessary for `so-long-mode-line-info' to have a non-nil
|
||
;; risky-local-variable property, as otherwise the text properties won't
|
||
;; be rendered.
|
||
`(so-long-mode-line-label
|
||
("" (:eval (propertize so-long-mode-line-label
|
||
'mouse-face 'highlight
|
||
'keymap ',map
|
||
'help-echo t ;; Suppress the mode-line value
|
||
'face (if so-long--active
|
||
'so-long-mode-line-active
|
||
'so-long-mode-line-inactive)))
|
||
" "))))
|
||
|
||
;; When the line's long
|
||
;; When the mode's slow
|
||
;; When Emacs is sad
|
||
;; We change automatically to faster code
|
||
;; And then I won't feel so mad
|
||
|
||
(defun so-long-detected-long-line-p ()
|
||
"Determine whether the current buffer contains long lines.
|
||
|
||
Following any initial comments and blank lines, the next N lines of the buffer
|
||
will be tested for excessive length (where \"excessive\" means above
|
||
`so-long-threshold', and N is `so-long-max-lines').
|
||
|
||
Returns non-nil if any such excessive-length line is detected.
|
||
|
||
If `so-long-skip-leading-comments' is nil then the N lines will be counted
|
||
starting from the first line of the buffer. In this instance you will likely
|
||
want to increase `so-long-max-lines' to allow for possible comments.
|
||
|
||
This is the default value of `so-long-predicate'."
|
||
(let ((count 0) start)
|
||
(save-excursion
|
||
(goto-char (point-min))
|
||
(when so-long-skip-leading-comments
|
||
;; Skip the shebang line, if any. This is not necessarily comment
|
||
;; syntax, so we need to treat it specially.
|
||
(when (looking-at "#!")
|
||
(forward-line 1))
|
||
;; Move past any leading whitespace and/or comments.
|
||
;; We use narrowing to limit the amount of text being processed at any
|
||
;; given time, where possible, as this makes things more efficient.
|
||
(setq start (point))
|
||
(while (save-restriction
|
||
(narrow-to-region start (min (+ (point) so-long-threshold)
|
||
(point-max)))
|
||
(goto-char start)
|
||
;; Possibilities for `comment-forward' are:
|
||
;; 0. No comment; no movement; return nil.
|
||
;; 1. Comment is <= point-max; move end of comment; return t.
|
||
;; 2. Comment is truncated; move point-max; return nil.
|
||
;; 3. Only whitespace; move end of WS; return nil.
|
||
(prog1 (or (comment-forward 1) ;; Moved past a comment.
|
||
(and (eobp) ;; Truncated, or WS up to point-max.
|
||
(progn ;; Widen and retry.
|
||
(widen)
|
||
(goto-char start)
|
||
(comment-forward 1))))
|
||
;; Otherwise there was no comment, and we return nil.
|
||
;; If there was whitespace, we moved past it.
|
||
(setq start (point)))))
|
||
;; We're at the first non-comment line, but we may have moved past
|
||
;; indentation whitespace, so move back to the beginning of the line
|
||
;; unless we're at the end of the buffer (in which case there was no
|
||
;; non-comment/whitespace content in the buffer at all).
|
||
(unless (eobp)
|
||
(forward-line 0)))
|
||
;; Start looking for long lines.
|
||
;; `while' will ultimately return nil if we do not `throw' a result.
|
||
(catch 'excessive
|
||
(while (and (not (eobp))
|
||
(or (not so-long-max-lines)
|
||
(< count so-long-max-lines)))
|
||
(setq start (point))
|
||
(save-restriction
|
||
(narrow-to-region start (min (+ start 1 so-long-threshold)
|
||
(point-max)))
|
||
(forward-line 1))
|
||
;; If point is not now at the beginning of a line, then the previous
|
||
;; line was long -- with the exception of when point is at the end of
|
||
;; the buffer (bearing in mind that we have widened again), in which
|
||
;; case there was a short final line with no newline. There is an
|
||
;; edge case when such a final line is exactly (1+ so-long-threshold)
|
||
;; chars long, so if we're at (eobp) we need to verify the length in
|
||
;; order to be consistent.
|
||
(unless (or (bolp)
|
||
(and (eobp) (<= (- (point) start)
|
||
so-long-threshold)))
|
||
(throw 'excessive t))
|
||
(setq count (1+ count)))))))
|
||
|
||
(defun so-long-function-longlines-mode ()
|
||
"Enable minor mode `longlines-mode'."
|
||
(require 'longlines)
|
||
(so-long-remember 'longlines-mode)
|
||
(longlines-mode 1))
|
||
|
||
(defun so-long-revert-function-longlines-mode ()
|
||
"Restore original state of `longlines-mode'."
|
||
(require 'longlines)
|
||
(let ((state (so-long-original 'longlines-mode :exists)))
|
||
(if state
|
||
(unless (equal (cadr state) longlines-mode)
|
||
(longlines-mode (if (cadr state) 1 0)))
|
||
(longlines-mode 0))))
|
||
|
||
(defun turn-on-so-long-minor-mode ()
|
||
"Enable minor mode `so-long-minor-mode'."
|
||
(so-long-minor-mode 1))
|
||
|
||
(defun turn-off-so-long-minor-mode ()
|
||
"Disable minor mode `so-long-minor-mode'."
|
||
(so-long-minor-mode 0))
|
||
|
||
;;;###autoload
|
||
(define-minor-mode so-long-minor-mode
|
||
"This is the minor mode equivalent of `so-long-mode'.
|
||
|
||
Any active minor modes listed in `so-long-minor-modes' are disabled for the
|
||
current buffer, and buffer-local values are assigned to variables in accordance
|
||
with `so-long-variable-overrides'.
|
||
|
||
This minor mode is a standard `so-long-action' option."
|
||
nil nil nil
|
||
(if so-long-minor-mode ;; We are enabling the mode.
|
||
(progn
|
||
;; Housekeeping. `so-long-minor-mode' might be invoked directly rather
|
||
;; than via `so-long', so replicate the necessary behaviours. The minor
|
||
;; mode also cares about whether `so-long' was already active, as we do
|
||
;; not want to remember values which were potentially overridden already.
|
||
(unless (or so-long--calling so-long--active)
|
||
(so-long--ensure-enabled)
|
||
(setq so-long--active t
|
||
so-long-detected-p t
|
||
so-long-function 'turn-on-so-long-minor-mode
|
||
so-long-revert-function 'turn-off-so-long-minor-mode)
|
||
(so-long-remember-all :reset)
|
||
(unless (derived-mode-p 'so-long-mode)
|
||
(setq so-long-mode-line-info (so-long-mode-line-info))))
|
||
;; Now perform the overrides.
|
||
(so-long-disable-minor-modes)
|
||
(so-long-override-variables))
|
||
;; We are disabling the mode.
|
||
(unless so-long--calling ;; Housekeeping.
|
||
(when (eq so-long-function 'turn-on-so-long-minor-mode)
|
||
(setq so-long--active nil))
|
||
(unless (derived-mode-p 'so-long-mode)
|
||
(setq so-long-mode-line-info (so-long-mode-line-info))))
|
||
;; Restore the overridden settings.
|
||
(so-long-restore-minor-modes)
|
||
(so-long-restore-variables)))
|
||
|
||
;; How do you solve a problem like a long line?
|
||
;; How do you stop a mode from slowing down?
|
||
;; How do you cope with processing a long line?
|
||
;; A bit of advice! A mode! A workaround!
|
||
|
||
(defvar so-long-mode-map
|
||
(let ((map (make-sparse-keymap)))
|
||
(define-key map (kbd "C-c C-c") 'so-long-revert)
|
||
;; Define the major mode menu. We have an awkward issue whereby
|
||
;; [menu-bar so-long] is already defined in the global map and is
|
||
;; :visible so-long-detected-p, but we also want this to be
|
||
;; available via the major mode construct in the mode line.
|
||
;; The following achieves the desired end result, as :visible nil
|
||
;; prevents this from duplicating its contents in the menu bar,
|
||
;; but still includes it in the mode line.
|
||
(define-key map [menu-bar so-long]
|
||
`(menu-item "" nil
|
||
:visible nil
|
||
:filter ,(lambda (_cmd) (so-long-menu))))
|
||
map)
|
||
"Major mode keymap and menu for `so-long-mode'.")
|
||
|
||
;;;###autoload
|
||
(define-derived-mode so-long-mode nil "So Long"
|
||
"This major mode is the default `so-long-action' option.
|
||
|
||
The normal reason for this mode being active is that `global-so-long-mode' is
|
||
enabled, and `so-long-predicate' has detected that the file contains long lines.
|
||
|
||
Many Emacs modes struggle with buffers which contain excessively long lines,
|
||
and may consequently cause unacceptable performance issues.
|
||
|
||
This is commonly on account of \"minified\" code (i.e. code that has been
|
||
compacted into the smallest file size possible, which often entails removing
|
||
newlines should they not be strictly necessary). These kinds of files are
|
||
typically not intended to be edited, so not providing the usual editing mode
|
||
in these cases will rarely be an issue.
|
||
|
||
This major mode disables any active minor modes listed in `so-long-minor-modes'
|
||
for the current buffer, and buffer-local values are assigned to variables in
|
||
accordance with `so-long-variable-overrides'.
|
||
|
||
To restore the original major mode (along with the minor modes and variable
|
||
values), despite potential performance issues, type \\[so-long-revert].
|
||
|
||
Use \\[so-long-commentary] for more information.
|
||
|
||
Use \\[so-long-customize] to configure the behaviour."
|
||
;; Housekeeping. `so-long-mode' might be invoked directly rather than via
|
||
;; `so-long', so replicate the necessary behaviours. We could use this same
|
||
;; test in `so-long-after-change-major-mode' to run `so-long-hook', but that's
|
||
;; not so obviously the right thing to do, so I've omitted it for now.
|
||
(unless so-long--calling
|
||
(so-long--ensure-enabled)
|
||
(setq so-long--active t
|
||
so-long-detected-p t
|
||
so-long-function 'so-long-mode
|
||
so-long-revert-function 'so-long-mode-revert))
|
||
;; Use `after-change-major-mode-hook' to disable minor modes and override
|
||
;; variables. Append, to act after any globalized modes have acted.
|
||
(add-hook 'after-change-major-mode-hook
|
||
'so-long-after-change-major-mode :append :local)
|
||
;; Override variables. This is the first of two instances where we do this
|
||
;; (the other being `so-long-after-change-major-mode'). It is desirable to
|
||
;; set variables here in order to cover cases where the setting of a variable
|
||
;; influences how a global minor mode behaves in this buffer.
|
||
(so-long-override-variables)
|
||
;; Hide redundant mode-line information (our major mode info replicates this).
|
||
(setq so-long-mode-line-info nil)
|
||
;; Inform the user about our major mode hijacking.
|
||
(unless (or so-long--inhibited so-long--set-auto-mode)
|
||
(message (concat "Changed to %s (from %s)"
|
||
(unless (or (eq this-command 'so-long)
|
||
(and (symbolp this-command)
|
||
(provided-mode-derived-p this-command
|
||
'so-long-mode)))
|
||
" on account of line length")
|
||
". %s to revert.")
|
||
major-mode
|
||
(or (so-long-original 'major-mode) "<unknown>")
|
||
(substitute-command-keys "\\[so-long-revert]"))))
|
||
|
||
(defun so-long--change-major-mode ()
|
||
;; Advice, enabled with:
|
||
;; (advice-add 'so-long-mode :before #'so-long--change-major-mode)
|
||
;;
|
||
;; n.b. `major-mode-suspend' and `major-mode-restore' are new in Emacs 27, and
|
||
;; related to what we're doing here; but it's not worth going to the effort of
|
||
;; using those (conditionally, only for 27+) when we have our own framework
|
||
;; for remembering and restoring this buffer state (amongst other things).
|
||
"Ensure that `so-long-mode' knows the original `major-mode'.
|
||
|
||
This advice acts before `so-long-mode', with the previous mode still active."
|
||
(unless (derived-mode-p 'so-long-mode)
|
||
;; Housekeeping. `so-long-mode' might be invoked directly rather than
|
||
;; via `so-long', so replicate the necessary behaviours.
|
||
(unless so-long--calling
|
||
(so-long-remember-all :reset))
|
||
;; Remember the original major mode, regardless.
|
||
(so-long-remember 'major-mode)))
|
||
|
||
(advice-add 'so-long-mode :before #'so-long--change-major-mode)
|
||
|
||
(defun so-long-after-change-major-mode ()
|
||
"Run by `so-long-mode' in `after-change-major-mode-hook'.
|
||
|
||
Calls `so-long-disable-minor-modes' and `so-long-override-variables'."
|
||
;; Disable minor modes.
|
||
(so-long-disable-minor-modes)
|
||
;; Override variables (again). We already did this in `so-long-mode' in
|
||
;; order that variables which affect global/globalized minor modes can have
|
||
;; that effect; however it's feasible that one of the minor modes disabled
|
||
;; above might have reverted one of these variables, so we re-enforce them.
|
||
;; (For example, disabling `visual-line-mode' sets `line-move-visual' to
|
||
;; nil, when for our purposes it is preferable for it to be non-nil).
|
||
(so-long-override-variables))
|
||
|
||
(defun so-long-disable-minor-modes ()
|
||
"Disable any active minor modes listed in `so-long-minor-modes'."
|
||
(dolist (mode so-long-minor-modes)
|
||
(when (and (boundp mode) mode)
|
||
(funcall mode 0))))
|
||
|
||
(defun so-long-restore-minor-modes ()
|
||
"Restore the minor modes which were disabled.
|
||
|
||
The modes are enabled in accordance with what was remembered in `so-long'."
|
||
(dolist (mode so-long-minor-modes)
|
||
(when (and (so-long-original mode)
|
||
(boundp mode)
|
||
(not (symbol-value mode)))
|
||
(funcall mode 1))))
|
||
|
||
(defun so-long-override-variables ()
|
||
"Set the buffer-local values defined by `so-long-variable-overrides'."
|
||
(dolist (ovar so-long-variable-overrides)
|
||
(set (make-local-variable (car ovar)) (cdr ovar))))
|
||
|
||
(defun so-long-restore-variables ()
|
||
"Restore the remembered values for the overridden variables.
|
||
|
||
The variables are set in accordance with what was remembered in `so-long'."
|
||
(dolist (ovar so-long-variable-overrides)
|
||
(so-long-restore-variable (car ovar))))
|
||
|
||
(defun so-long-restore-variable (variable)
|
||
"Restore the remembered value (if any) for VARIABLE."
|
||
;; In the instance where `so-long-mode-revert' has just reverted the major
|
||
;; mode, note that `kill-all-local-variables' was already called by the
|
||
;; original mode function, and so these 'overridden' variables may now have
|
||
;; global rather than buffer-local values.
|
||
(let* ((remembered (so-long-original variable :exists))
|
||
(originally-local (nth 2 remembered)))
|
||
(if originally-local
|
||
;; The variable originally existed with a buffer-local value, so we
|
||
;; restore it as such (even if the global value is a match).
|
||
(set (make-local-variable variable) (cadr remembered))
|
||
;; Either this variable did not exist initially, or it did not have a
|
||
;; buffer-local value at that time. In either case we kill the current
|
||
;; buffer-local value (if any) in order to restore the original state.
|
||
;;
|
||
;; It's possible that the global value has *changed* in the interim; but
|
||
;; we can't know whether it's best to use the new global value, or retain
|
||
;; the old value as a buffer-local value, so we keep it simple.
|
||
(kill-local-variable variable))))
|
||
|
||
(defun so-long-mode-revert ()
|
||
"Call the `major-mode' which was selected before `so-long-mode' replaced it.
|
||
|
||
Re-process local variables, and restore overridden variables and minor modes.
|
||
|
||
This is the `so-long-revert-function' for `so-long-mode'."
|
||
(interactive)
|
||
(let ((so-long-original-mode (so-long-original 'major-mode)))
|
||
(unless so-long-original-mode
|
||
(error "Original mode unknown."))
|
||
(funcall so-long-original-mode)
|
||
;; Emacs 26+ has already called `hack-local-variables' (during
|
||
;; `run-mode-hooks'; provided there was a `buffer-file-name'), but for older
|
||
;; versions we need to call it here. In Emacs 26+ the revised 'HANDLE-MODE'
|
||
;; argument is set to `no-mode' (being the non-nil-and-non-t behaviour),
|
||
;; which we mimic here by binding `so-long--hack-local-variables-no-mode',
|
||
;; in order to prevent a local 'mode' variable from clobbering the major
|
||
;; mode we have just called.
|
||
(when (< emacs-major-version 26)
|
||
(let ((so-long--hack-local-variables-no-mode t))
|
||
(hack-local-variables)))
|
||
;; Restore minor modes.
|
||
(so-long-restore-minor-modes)
|
||
;; Restore overridden variables.
|
||
;; `kill-all-local-variables' was already called by the original mode
|
||
;; function, so we may be seeing global values.
|
||
(so-long-restore-variables)
|
||
;; Restore the mode line construct.
|
||
(unless (derived-mode-p 'so-long-mode)
|
||
(setq so-long-mode-line-info (so-long-mode-line-info)))))
|
||
|
||
(defun so-long-mode-downgrade (&optional mode)
|
||
"The default value for `so-long-file-local-mode-function'.
|
||
|
||
A buffer-local \"downgrade\" from `so-long-mode' to `so-long-minor-mode'.
|
||
|
||
When `so-long-function' is set to `so-long-mode', then we change it to
|
||
`turn-on-so-long-minor-mode' instead -- retaining the file-local major
|
||
mode, but still doing everything else that `so-long-mode' would have done.
|
||
`so-long-revert-function' is likewise updated.
|
||
|
||
If `so-long-function' has any value other than `so-long-mode', we do nothing,
|
||
as if `so-long-file-local-mode-function' was nil.
|
||
|
||
We also do nothing if MODE (the file-local mode) has the value `so-long-mode',
|
||
because we do not want to downgrade the major mode in that scenario."
|
||
;; Do nothing if the file-local mode was `so-long-mode'.
|
||
(unless (provided-mode-derived-p mode 'so-long-mode)
|
||
;; Act only if `so-long-mode' would be enabled by the current action.
|
||
(when (and (symbolp (so-long-function))
|
||
(provided-mode-derived-p (so-long-function) 'so-long-mode))
|
||
;; Downgrade from `so-long-mode' to the `so-long-minor-mode' behaviour.
|
||
(setq so-long-function 'turn-on-so-long-minor-mode
|
||
so-long-revert-function 'turn-off-so-long-minor-mode))))
|
||
|
||
(defun so-long-inhibit (&optional _mode)
|
||
"Prevent so-long from having any effect at all.
|
||
|
||
This is a `so-long-file-local-mode-function' option."
|
||
(setq so-long--inhibited t))
|
||
|
||
(defun so-long--check-header-modes ()
|
||
;; See also "Files with a file-local 'mode'" in the Commentary.
|
||
"Handle the header-comments processing in `set-auto-mode'.
|
||
|
||
`set-auto-mode' has some special-case code to handle the `mode' pseudo-variable
|
||
when set in the header comment. This runs outside of `hack-local-variables'
|
||
and cannot be conveniently intercepted, so we are forced to replicate it here.
|
||
|
||
This special-case code will ultimately be removed from Emacs, as it exists to
|
||
deal with a deprecated feature; but until then we need to replicate it in order
|
||
to inhibit our own behaviour in the presence of a header comment `mode'
|
||
declaration.
|
||
|
||
If a file-local mode is detected in the header comment, then we call the
|
||
function defined by `so-long-file-local-mode-function'."
|
||
;; The following code for processing MODE declarations in the header
|
||
;; comments is copied verbatim from `set-auto-mode', because we have
|
||
;; no way of intercepting it.
|
||
;;
|
||
(let ((try-locals (not (inhibit-local-variables-p)))
|
||
end _done _mode modes)
|
||
;; Once we drop the deprecated feature where mode: is also allowed to
|
||
;; specify minor-modes (ie, there can be more than one "mode:"), we can
|
||
;; remove this section and just let (hack-local-variables t) handle it.
|
||
;; Find a -*- mode tag.
|
||
(save-excursion
|
||
(goto-char (point-min))
|
||
(skip-chars-forward " \t\n")
|
||
;; Note by design local-enable-local-variables does not matter here.
|
||
(and enable-local-variables
|
||
try-locals
|
||
(setq end (set-auto-mode-1))
|
||
(if (save-excursion (search-forward ":" end t))
|
||
;; Find all specifications for the `mode:' variable
|
||
;; and execute them left to right.
|
||
(while (let ((case-fold-search t))
|
||
(or (and (looking-at "mode:")
|
||
(goto-char (match-end 0)))
|
||
(re-search-forward "[ \t;]mode:" end t)))
|
||
(skip-chars-forward " \t")
|
||
(let ((beg (point)))
|
||
(if (search-forward ";" end t)
|
||
(forward-char -1)
|
||
(goto-char end))
|
||
(skip-chars-backward " \t")
|
||
(push (intern (concat (downcase (buffer-substring
|
||
beg (point)))
|
||
"-mode"))
|
||
modes)))
|
||
;; Simple -*-MODE-*- case.
|
||
(push (intern (concat (downcase (buffer-substring (point) end))
|
||
"-mode"))
|
||
modes))))
|
||
|
||
;; `so-long' now processes the resulting mode list. If any modes were
|
||
;; listed, we assume that one of them is a major mode. It's possible that
|
||
;; this isn't true, but the buffer would remain in fundamental-mode if that
|
||
;; were the case, so it is very unlikely. For the purposes of passing a
|
||
;; value to `so-long-handle-file-local-mode' we assume the major mode was
|
||
;; the first mode specified (in which case it is the last in the list).
|
||
(when modes
|
||
(so-long-handle-file-local-mode (car (last modes))))))
|
||
|
||
;; Lisp advice, Lisp advice
|
||
;; Every calling you greet me
|
||
;; Code of mine, redefined
|
||
;; You look happy to tweak me
|
||
|
||
(defun so-long--hack-local-variables (orig-fun &optional handle-mode &rest args)
|
||
;; Advice, enabled with:
|
||
;; (advice-add 'hack-local-variables :around #'so-long--hack-local-variables)
|
||
;;
|
||
;; See also "Files with a file-local 'mode'" in the Commentary.
|
||
"Ensure that `so-long' defers to file-local mode declarations if necessary.
|
||
|
||
If a file-local mode is detected, then we call the function defined by
|
||
`so-long-file-local-mode-function'.
|
||
|
||
This advice acts after the HANDLE-MODE:t call to `hack-local-variables'.
|
||
\(MODE-ONLY in Emacs versions < 26).
|
||
|
||
File-local header comments are currently an exception, and are processed by
|
||
`so-long--check-header-modes' (see which for details)."
|
||
;; The first arg to `hack-local-variables' is HANDLE-MODE since Emacs 26.1,
|
||
;; and MODE-ONLY in earlier versions. In either case we are interested in
|
||
;; whether it has the value `t'.
|
||
(let ((retval (apply orig-fun handle-mode args)))
|
||
(and (eq handle-mode t)
|
||
retval ; A file-local mode was set.
|
||
(so-long-handle-file-local-mode retval))
|
||
retval))
|
||
|
||
(defun so-long--set-auto-mode (orig-fun &rest args)
|
||
;; Advice, enabled with:
|
||
;; (advice-add 'set-auto-mode :around #'so-long--set-auto-mode)
|
||
"Maybe call `so-long' for files with very long lines.
|
||
|
||
This advice acts after `set-auto-mode' has set the buffer's major mode.
|
||
|
||
We can't act before this point, because some major modes must be exempt
|
||
\(binary file modes, for example). Instead, we act only when the selected
|
||
major mode is a member (or derivative of a member) of `so-long-target-modes'.
|
||
|
||
`so-long-predicate' then determines whether the mode change is needed."
|
||
(setq so-long--inhibited nil) ; is permanent-local
|
||
(when so-long-enabled
|
||
(so-long--check-header-modes)) ; may cause `so-long--inhibited' to be set.
|
||
(let ((so-long--set-auto-mode t))
|
||
;; Call `set-auto-mode'.
|
||
(apply orig-fun args)) ; may cause `so-long--inhibited' to be set.
|
||
;; Test the new major mode for long lines.
|
||
(and so-long-enabled
|
||
(not so-long--inhibited)
|
||
(not so-long--calling)
|
||
(or (eq so-long-target-modes t)
|
||
(apply #'derived-mode-p so-long-target-modes))
|
||
(setq so-long-detected-p (funcall so-long-predicate))
|
||
;; `so-long' should be called; but only if and when the buffer is
|
||
;; displayed in a window. Long lines in invisible buffers are generally
|
||
;; not problematic, whereas it might cause problems if an invisible
|
||
;; buffer being used for behind-the-scenes processing is manipulated
|
||
;; unexpectedly. The default `so-long-invisible-buffer-function' value
|
||
;; is `so-long-deferred', which arranges to call `so-long' as soon as
|
||
;; the buffer is displayed.
|
||
(if (or (get-buffer-window (current-buffer) t)
|
||
(not so-long-invisible-buffer-function))
|
||
(so-long)
|
||
(funcall so-long-invisible-buffer-function))))
|
||
|
||
(defun so-long--hack-one-local-variable (orig-fun var val)
|
||
;; Advice, enabled with:
|
||
;; (advice-add 'hack-one-local-variable :around
|
||
;; #'so-long--hack-one-local-variable)
|
||
"Prevent the original major mode being restored after `so-long-mode'.
|
||
|
||
This advice is needed and enabled only for Emacs versions < 26.1.
|
||
|
||
If the local `mode' pseudo-variable is used, `set-auto-mode-0' will call it
|
||
firstly, and subsequently `hack-one-local-variable' may call it again.
|
||
|
||
Usually `hack-one-local-variable' tries to avoid processing that second call,
|
||
by testing the value against `major-mode'; but as we may have changed the
|
||
major mode to `so-long-mode' by this point, that protection is insufficient
|
||
and so we need to perform our own test.
|
||
|
||
We likewise need to support an equivalent of the `no-mode' behaviour in 26.1+
|
||
to ensure that `so-long-mode-revert' will not restore a file-local mode again
|
||
after it has already reverted to the original mode.
|
||
|
||
The changes to `normal-mode' in Emacs 26.1 modified the execution order, and
|
||
makes this advice unnecessary. The relevant NEWS entry is:
|
||
|
||
** File local and directory local variables are now initialized each
|
||
time the major mode is set, not just when the file is first visited.
|
||
These local variables will thus not vanish on setting a major mode."
|
||
(if (eq var 'mode)
|
||
;; Adapted directly from `hack-one-local-variable'
|
||
(let ((mode (intern (concat (downcase (symbol-name val))
|
||
"-mode"))))
|
||
(unless (or so-long--hack-local-variables-no-mode
|
||
(let ((origmode (so-long-original 'major-mode)))
|
||
;; We bind origmode because (indirect-function nil) is an
|
||
;; error in Emacs versions < 25.1, and so we need to test
|
||
;; it first.
|
||
(and origmode
|
||
(eq (indirect-function mode)
|
||
(indirect-function origmode)))))
|
||
(funcall orig-fun var val)))
|
||
;; VAR is not the 'mode' pseudo-variable.
|
||
(funcall orig-fun var val)))
|
||
|
||
(defun so-long-deferred ()
|
||
"Arrange to call `so-long' if the current buffer is displayed in a window."
|
||
;; The first time that a window-configuration change results in the buffer
|
||
;; being displayed in a window, `so-long' will be called (with the window
|
||
;; selected and the buffer set as current). Because `so-long' removes this
|
||
;; buffer-local hook value, it triggers once at most.
|
||
(add-hook 'window-configuration-change-hook #'so-long nil :local))
|
||
|
||
;;;###autoload
|
||
(defun so-long (&optional action)
|
||
"Invoke `so-long-action' and run `so-long-hook'.
|
||
|
||
This command is called automatically when long lines are detected, when
|
||
`global-so-long-mode' is enabled.
|
||
|
||
The effects of the action can be undone by calling `so-long-revert'.
|
||
|
||
If ACTION is provided, it is used instead of `so-long-action'. With a prefix
|
||
argument, select the action to use interactively."
|
||
(interactive
|
||
(list (and current-prefix-arg
|
||
(intern
|
||
(completing-read "Action (none): "
|
||
(mapcar #'car so-long-action-alist)
|
||
nil :require-match)))))
|
||
;; Ensure that `so-long-deferred' only triggers `so-long' once (at most).
|
||
(remove-hook 'window-configuration-change-hook #'so-long :local)
|
||
(unless so-long--calling
|
||
(let ((so-long--calling t))
|
||
(so-long--ensure-enabled)
|
||
;; ACTION takes precedence if supplied.
|
||
(when action
|
||
(setq so-long-function nil
|
||
so-long-revert-function nil))
|
||
;; Some of these settings need to be duplicated in `so-long-mode' to cover
|
||
;; the case when that mode is invoked directly.
|
||
(setq so-long-detected-p t) ;; ensure menu is present.
|
||
(unless so-long-function
|
||
(setq so-long-function (so-long-function action)))
|
||
(unless so-long-revert-function
|
||
(setq so-long-revert-function (so-long-revert-function action)))
|
||
;; Remember original settings.
|
||
(so-long-remember-all :reset)
|
||
;; Call the configured `so-long-function'.
|
||
(when so-long-function
|
||
(funcall so-long-function)
|
||
;; Set `so-long--active' last, as it isn't permanent-local.
|
||
(setq so-long--active t))
|
||
;; Display mode line info, unless we are in `so-long-mode' (which provides
|
||
;; equivalent information in the mode line construct for the major mode).
|
||
(unless (derived-mode-p 'so-long-mode)
|
||
(setq so-long-mode-line-info (so-long-mode-line-info)))
|
||
;; Run `so-long-hook'.
|
||
;; By default we set `buffer-read-only', which can cause problems if hook
|
||
;; functions need to modify the buffer. We use `inhibit-read-only' to
|
||
;; side-step the issue (and likewise in `so-long-revert').
|
||
(let ((inhibit-read-only t))
|
||
(run-hooks 'so-long-hook)))))
|
||
|
||
(defun so-long-revert ()
|
||
"Revert the active `so-long-action' and run `so-long-revert-hook'.
|
||
|
||
This undoes the effects of the `so-long' command (which is normally called
|
||
automatically by `global-so-long-mode').
|
||
|
||
For the default action, reverting will restore the original major mode, and
|
||
restore the minor modes and settings which were overridden when `so-long' was
|
||
invoked."
|
||
(interactive)
|
||
(unless so-long--calling
|
||
(let ((so-long--calling t))
|
||
(when so-long-revert-function
|
||
(funcall so-long-revert-function)
|
||
(setq so-long--active nil))
|
||
(let ((inhibit-read-only t))
|
||
(run-hooks 'so-long-revert-hook)))))
|
||
|
||
;; Duplicate the `so-long-revert' documentation for the menu item.
|
||
(put 'so-long-menu-item-revert 'function-documentation
|
||
(documentation 'so-long-revert t))
|
||
|
||
;;;###autoload
|
||
(defun so-long-enable ()
|
||
"Enable the so-long library's functionality.
|
||
|
||
Equivalent to calling (global-so-long-mode 1)"
|
||
(interactive)
|
||
(global-so-long-mode 1))
|
||
|
||
(defun so-long-disable ()
|
||
"Disable the so-long library's functionality.
|
||
|
||
Equivalent to calling (global-so-long-mode 0)"
|
||
(interactive)
|
||
(global-so-long-mode 0))
|
||
|
||
(make-obsolete 'so-long-enable 'global-so-long-mode "so-long 1.0")
|
||
(make-obsolete 'so-long-disable 'global-so-long-mode "so-long 1.0")
|
||
|
||
;;;###autoload
|
||
(define-minor-mode global-so-long-mode
|
||
"Toggle automated performance mitigations for files with long lines.
|
||
|
||
Many Emacs modes struggle with buffers which contain excessively long lines,
|
||
and may consequently cause unacceptable performance issues.
|
||
|
||
This is commonly on account of \"minified\" code (i.e. code that has been
|
||
compacted into the smallest file size possible, which often entails removing
|
||
newlines should they not be strictly necessary).
|
||
|
||
When such files are detected by `so-long-predicate', we invoke the selected
|
||
`so-long-action' to mitigate potential performance problems in the buffer.
|
||
|
||
Use \\[so-long-commentary] for more information.
|
||
|
||
Use \\[so-long-customize] to configure the behaviour."
|
||
:global t
|
||
:group 'so-long
|
||
(if global-so-long-mode
|
||
;; Enable
|
||
(progn
|
||
(so-long--enable)
|
||
(advice-add 'hack-local-variables :around
|
||
#'so-long--hack-local-variables)
|
||
(advice-add 'set-auto-mode :around
|
||
#'so-long--set-auto-mode)
|
||
(when (< emacs-major-version 26)
|
||
(advice-add 'hack-one-local-variable :around
|
||
#'so-long--hack-one-local-variable)))
|
||
;; Disable
|
||
(so-long--disable)
|
||
(advice-remove 'hack-local-variables #'so-long--hack-local-variables)
|
||
(advice-remove 'set-auto-mode #'so-long--set-auto-mode)
|
||
(when (< emacs-major-version 26)
|
||
(advice-remove 'hack-one-local-variable
|
||
#'so-long--hack-one-local-variable))))
|
||
|
||
(put 'global-so-long-mode 'variable-documentation
|
||
"Non-nil if the so-long library's automated functionality is enabled.
|
||
|
||
Use \\[so-long-commentary] for more information.
|
||
|
||
Setting this variable directly does not take effect;
|
||
either customize it (see the info node `Easy Customization')
|
||
or call the function `global-so-long-mode'.")
|
||
|
||
(defun so-long--ensure-enabled ()
|
||
"Enable essential functionality, if not already enabled."
|
||
(unless so-long-enabled
|
||
(so-long--enable)))
|
||
|
||
(defun so-long--enable ()
|
||
"Enable functionality other than `global-so-long-mode'."
|
||
(add-to-list 'mode-line-misc-info '("" so-long-mode-line-info))
|
||
(define-key-after (current-global-map) [menu-bar so-long]
|
||
`(menu-item "So Long" nil
|
||
;; See also `so-long-mode-map'.
|
||
:visible (or so-long--active
|
||
so-long-detected-p
|
||
(derived-mode-p 'so-long-mode))
|
||
:filter ,(lambda (_cmd) (so-long-menu))))
|
||
(setq so-long-enabled t))
|
||
|
||
(defun so-long--disable ()
|
||
"Disable functionality other than `global-so-long-mode'."
|
||
(setq mode-line-misc-info
|
||
(delete '("" so-long-mode-line-info) mode-line-misc-info))
|
||
(define-key (current-global-map) [menu-bar so-long] nil)
|
||
(setq so-long-enabled nil))
|
||
|
||
(defun so-long-unload-function ()
|
||
"Handler for `unload-feature'."
|
||
(condition-case err
|
||
(progn
|
||
(global-so-long-mode 0)
|
||
;; Process existing buffers.
|
||
(dolist (buf (buffer-list))
|
||
(with-current-buffer buf
|
||
;; Remove buffer-local `window-configuration-change-hook' values set
|
||
;; by `so-long-deferred'.
|
||
(remove-hook 'window-configuration-change-hook #'so-long :local)
|
||
;; Call `so-long-revert' in all buffers where so-long is active.
|
||
(when (bound-and-true-p so-long--active)
|
||
(so-long-revert))))
|
||
;; Un-define our buffer-local variables, as `unload-feature' will not do
|
||
;; this automatically. We remove them from `unload-function-defs-list'
|
||
;; as well, to prevent them being redefined. n.b.: `so-long--active' is
|
||
;; tested (above) using `bound-and-true-p' because that is one of the
|
||
;; variables which we unbind (below); and if something subsequent to
|
||
;; this handler signals an error, the user may need to call this again.
|
||
(defvar unload-function-defs-list)
|
||
(dolist (var '(so-long--active
|
||
so-long--inhibited
|
||
so-long-detected-p
|
||
so-long-file-local-mode-function
|
||
so-long-function
|
||
so-long-minor-mode
|
||
so-long-mode-abbrev-table
|
||
so-long-mode-line-info
|
||
so-long-mode-syntax-table
|
||
so-long-original-values
|
||
so-long-revert-function))
|
||
(makunbound var)
|
||
(setq unload-function-defs-list
|
||
(delq var unload-function-defs-list)))
|
||
;; Return nil if unloading was successful. Refer to `unload-feature'.
|
||
nil)
|
||
;; If any error occurred, return non-nil.
|
||
(error (progn
|
||
(message "Error unloading so-long: %S %S" (car err) (cdr err))
|
||
t))))
|
||
|
||
;; Backwards-compatibility definitions.
|
||
;;
|
||
;; The following obsolete functions may exist in the user's customized hook
|
||
;; values dating from versions < 1.0, so we need to ensure that such saved
|
||
;; values will not trigger errors.
|
||
(cl-flet ((ignore () nil))
|
||
(dolist (hookfunc '((so-long-inhibit-whitespace-mode . so-long-hook)
|
||
(so-long-make-buffer-read-only . so-long-hook)
|
||
(so-long-revert-buffer-read-only . so-long-revert-hook)
|
||
(so-long-inhibit-global-hl-line-mode . so-long-mode-hook)))
|
||
(defalias (car hookfunc) #'ignore
|
||
(format "Obsolete function. It now does nothing.
|
||
|
||
If it appears in `%s', you should remove it."
|
||
(cdr hookfunc)))
|
||
(make-obsolete (car hookfunc) nil "so-long.el version 1.0")))
|
||
|
||
;; Live upgrades, for when a newer version is loaded over an older one.
|
||
;;
|
||
;; If `so-long-version' was already bound then that tells us which version we
|
||
;; should upgrade from. If `so-long-version' is unbound then most likely there
|
||
;; was no older version loaded; however, prior to version 1.0 `so-long-version'
|
||
;; was not defined at all, and so we also need to detect that scenario, which
|
||
;; we can do by testing for the presence of a symbol which was removed in 1.0.
|
||
;;
|
||
;; The variable `so-long-mode-enabled' covers versions 0.5 - 0.7.6, which is
|
||
;; every pre-1.0 release using the name "so-long.el".
|
||
(defvar so-long-version (if (boundp 'so-long-mode-enabled)
|
||
"0.5" ;; >= 0.5 and < 1.0
|
||
so-long--latest-version)
|
||
"The loaded version of so-long.el.")
|
||
|
||
;; Version-specific updates.
|
||
(when (version< so-long-version so-long--latest-version)
|
||
;; Perform each update in sequence, as necessary.
|
||
;; Update to version 1.0 from earlier versions:
|
||
(when (version< so-long-version "1.0")
|
||
(remove-hook 'change-major-mode-hook 'so-long-change-major-mode)
|
||
(require 'advice)
|
||
(when (ad-find-advice 'hack-local-variables 'after 'so-long--file-local-mode)
|
||
(ad-remove-advice 'hack-local-variables 'after 'so-long--file-local-mode)
|
||
(ad-activate 'hack-local-variables))
|
||
(when (ad-find-advice 'set-auto-mode 'around 'so-long--set-auto-mode)
|
||
(ad-remove-advice 'set-auto-mode 'around 'so-long--set-auto-mode)
|
||
(ad-activate 'set-auto-mode))
|
||
(when (boundp 'so-long-mode-map)
|
||
(define-key so-long-mode-map [remap so-long-mode-revert] #'so-long-revert))
|
||
(dolist (var '(so-long-mode--inhibited
|
||
so-long-original-mode))
|
||
(makunbound var))
|
||
(dolist (func '(so-long-change-major-mode
|
||
so-long-check-header-modes
|
||
so-long-line-detected-p))
|
||
(fmakunbound func))
|
||
(defvar so-long-mode-enabled)
|
||
(when so-long-mode-enabled
|
||
(unless global-so-long-mode
|
||
(global-so-long-mode 1)))
|
||
(makunbound 'so-long-mode-enabled))
|
||
;; Update to version 1.N:
|
||
;; (when (version< so-long-version "1.N") ...)
|
||
;;
|
||
;; All updates completed.
|
||
(setq so-long-version so-long--latest-version))
|
||
|
||
|
||
(provide 'so-long)
|
||
|
||
;; Local Variables:
|
||
;; emacs-lisp-docstring-fill-column: 80
|
||
;; fill-column: 80
|
||
;; indent-tabs-mode: nil
|
||
;; ispell-check-comments: exclusive
|
||
;; ispell-local-dictionary: "british"
|
||
;; End:
|
||
|
||
;; This library is extensively documented in British English, contrary to the
|
||
;; preference for American English in Emacs. I hope the benefits of the library
|
||
;; will outweigh any discontent you may experience regarding the spelling (or
|
||
;; that you find the spelling to be an agreeable bonus). Certain standard Emacs
|
||
;; terminology, and text quoted from elsewhere in Emacs, retains its original
|
||
;; spelling. The following LocalWords should result in no misspellings from
|
||
;; M-x ispell-buffer (using aspell).
|
||
|
||
; LocalWords: LocalWords british ispell aspell hunspell emacs elisp el init dir
|
||
; LocalWords: customize customized customizing Customization globalized amongst
|
||
; LocalWords: initialized profiler boolean minified pre redisplay config keymap
|
||
; LocalWords: noerror selectable mapc sgml nxml hl flydiff defs arg Phil Sainty
|
||
; LocalWords: defadvice nadvice whitespace ie bos eos eobp origmode un Un cXXXr
|
||
; LocalWords: docstring auf wiedersehen longlines alist autoload Refactored Inc
|
||
; LocalWords: MERCHANTABILITY RET REGEXP VAR ELPA WS mitigations EmacsWiki eval
|
||
; LocalWords: setq rx filename filenames
|
||
|
||
;; So long, farewell, auf wiedersehen, goodbye
|
||
;; You have to go, this code is minified
|
||
;; Goodbye!
|
||
|
||
;;; so-long.el ends here
|