diff options
Diffstat (limited to 'lisp/follow.el')
| -rw-r--r-- | lisp/follow.el | 141 |
1 files changed, 69 insertions, 72 deletions
diff --git a/lisp/follow.el b/lisp/follow.el index 069758747c1..dde140d0fd5 100644 --- a/lisp/follow.el +++ b/lisp/follow.el @@ -1,4 +1,4 @@ -;;; follow.el --- synchronize windows showing the same buffer +;;; follow.el --- synchronize windows showing the same buffer -*- lexical-binding: t -*- ;; Copyright (C) 1995-1997, 1999, 2001-2021 Free Software Foundation, ;; Inc. @@ -25,7 +25,7 @@ ;;; Commentary: -;; `Follow mode' is a minor mode that combines windows into one tall +;; `follow-mode' is a minor mode that combines windows into one tall ;; virtual window. ;; ;; The feeling of a "virtual window" has been accomplished by the use @@ -81,7 +81,7 @@ ;; text. Enter long lines spanning several lines, or several ;; windows. ;; -;; * Should you find `Follow' mode annoying, just type +;; * Should you find Follow mode annoying, just type ;; M-x follow-mode <RETURN> ;; to turn it off. @@ -93,25 +93,24 @@ ;; key map. To do so, add the following lines (replacing `[f7]' and ;; `[f8]' with your favorite keys) to the init file: ;; -;; (global-set-key [f8] 'follow-mode) -;; (global-set-key [f7] 'follow-delete-other-windows-and-split) +;; (global-set-key [f8] #'follow-mode) +;; (global-set-key [f7] #'follow-delete-other-windows-and-split) ;; There exist two system variables that control the appearance of ;; lines wider than the window containing them. The default is to ;; truncate long lines whenever a window isn't as wide as the frame. ;; -;; To make sure lines are never truncated, please place the following -;; lines in your init file: +;; To make sure lines are never truncated, place the following lines +;; in your Init file: ;; ;; (setq truncate-lines nil) ;; (setq truncate-partial-width-windows nil) -;; The correct way to configure Follow mode, or any other mode for -;; that matter, is to create one or more functions that do -;; whatever you would like to do. These functions are then added to -;; a hook. +;; One way to configure Follow mode is to create one or more functions +;; that do whatever you would like to do. These functions are then +;; added to a hook. ;; ;; The keymap `follow-mode-map' contains key bindings activated by ;; `follow-mode'. @@ -120,8 +119,8 @@ ;; (add-hook 'follow-mode-hook 'my-follow-mode-hook) ;; ;; (defun my-follow-mode-hook () -;; (define-key follow-mode-map "\C-ca" 'your-favorite-function) -;; (define-key follow-mode-map "\C-cb" 'another-function)) +;; (define-key follow-mode-map "\C-ca" #'your-favorite-function) +;; (define-key follow-mode-map "\C-cb" #'another-function)) ;; Usage: @@ -129,60 +128,60 @@ ;; To activate, issue the command "M-x follow-mode" ;; and press Return. To deactivate, do it again. ;; -;; The following is a list of commands useful when follow-mode is active. +;; The following is a list of commands useful when `follow-mode' is active. ;; -;; follow-scroll-up C-c . C-v +;; `follow-scroll-up' C-c . C-v ;; Scroll text in a Follow mode window chain up. ;; -;; follow-scroll-down C-c . v +;; `follow-scroll-down' C-c . v ;; Like `follow-scroll-up', but in the other direction. ;; -;; follow-delete-other-windows-and-split C-c . 1 +;; `follow-delete-other-windows-and-split' C-c . 1 ;; Maximize the visible area of the current buffer, -;; and enter Follow mode. This is a very convenient +;; and enter Follow mode. This is a very convenient ;; way to start Follow mode, hence we recommend that ;; this command be added to the global keymap. ;; -;; follow-recenter C-c . C-l +;; `follow-recenter' C-c . C-l ;; Place point in the center of the middle window, ;; or a specified number of lines from either top or bottom. ;; -;; follow-switch-to-buffer C-c . b +;; `follow-switch-to-buffer' C-c . b ;; Switch buffer in all windows displaying the current buffer ;; in this frame. ;; -;; follow-switch-to-buffer-all C-c . C-b +;; `follow-switch-to-buffer-all' C-c . C-b ;; Switch buffer in all windows in the selected frame. ;; -;; follow-switch-to-current-buffer-all +;; `follow-switch-to-current-buffer-all' ;; Show the current buffer in all windows on the current ;; frame and turn on `follow-mode'. ;; -;; follow-first-window C-c . < +;; `follow-first-window' C-c . < ;; Select the first window in the frame showing the same buffer. ;; -;; follow-last-window C-c . > +;; `follow-last-window' C-c . > ;; Select the last window in the frame showing the same buffer. ;; -;; follow-next-window C-c . n +;; `follow-next-window' C-c . n ;; Select the next window in the frame showing the same buffer. ;; -;; follow-previous-window C-c . p +;; `follow-previous-window' C-c . p ;; Select the previous window showing the same buffer. ;; Well, it seems ok, but what if I really want to look at two different -;; positions in the text? Here are two simple methods to use: +;; positions in the text? Here are two simple methods to use: ;; ;; 1) Use multiple frames; `follow' mode only affects windows displayed -;; in the same frame. (My apologies to you who can't use frames.) +;; in the same frame. (My apologies to you who can't use frames.) ;; ;; 2) Bind `follow-mode' to key so you can turn it off whenever -;; you want to view two locations. Of course, `follow' mode can +;; you want to view two locations. Of course, `follow-mode' can ;; be reactivated by hitting the same key again. ;; ;; Example from my ~/.emacs: -;; (global-set-key [f8] 'follow-mode) +;; (global-set-key [f8] #'follow-mode) ;; Implementation: ;; @@ -201,7 +200,6 @@ ;;; Code: -(require 'easymenu) (eval-when-compile (require 'cl-lib)) ;;; Variables @@ -236,17 +234,17 @@ After that, changing the prefix key requires manipulating keymaps." (defvar follow-mode-map (let ((mainmap (make-sparse-keymap)) (map (make-sparse-keymap))) - (define-key map "\C-v" 'follow-scroll-up) - (define-key map "\M-v" 'follow-scroll-down) - (define-key map "v" 'follow-scroll-down) - (define-key map "1" 'follow-delete-other-windows-and-split) - (define-key map "b" 'follow-switch-to-buffer) - (define-key map "\C-b" 'follow-switch-to-buffer-all) - (define-key map "\C-l" 'follow-recenter) - (define-key map "<" 'follow-first-window) - (define-key map ">" 'follow-last-window) - (define-key map "n" 'follow-next-window) - (define-key map "p" 'follow-previous-window) + (define-key map "\C-v" #'follow-scroll-up) + (define-key map "\M-v" #'follow-scroll-down) + (define-key map "v" #'follow-scroll-down) + (define-key map "1" #'follow-delete-other-windows-and-split) + (define-key map "b" #'follow-switch-to-buffer) + (define-key map "\C-b" #'follow-switch-to-buffer-all) + (define-key map "\C-l" #'follow-recenter) + (define-key map "<" #'follow-first-window) + (define-key map ">" #'follow-last-window) + (define-key map "n" #'follow-next-window) + (define-key map "p" #'follow-previous-window) (define-key mainmap follow-mode-prefix map) @@ -255,13 +253,13 @@ After that, changing the prefix key requires manipulating keymaps." ;; could be enhanced in Follow mode. End-of-buffer is a special ;; case since it is very simple to define and it greatly enhances ;; the look and feel of Follow mode.) - (define-key mainmap [remap end-of-buffer] 'follow-end-of-buffer) + (define-key mainmap [remap end-of-buffer] #'follow-end-of-buffer) - (define-key mainmap [remap scroll-bar-toolkit-scroll] 'follow-scroll-bar-toolkit-scroll) - (define-key mainmap [remap scroll-bar-drag] 'follow-scroll-bar-drag) - (define-key mainmap [remap scroll-bar-scroll-up] 'follow-scroll-bar-scroll-up) - (define-key mainmap [remap scroll-bar-scroll-down] 'follow-scroll-bar-scroll-down) - (define-key mainmap [remap mwheel-scroll] 'follow-mwheel-scroll) + (define-key mainmap [remap scroll-bar-toolkit-scroll] #'follow-scroll-bar-toolkit-scroll) + (define-key mainmap [remap scroll-bar-drag] #'follow-scroll-bar-drag) + (define-key mainmap [remap scroll-bar-scroll-up] #'follow-scroll-bar-scroll-up) + (define-key mainmap [remap scroll-bar-scroll-down] #'follow-scroll-bar-scroll-down) + (define-key mainmap [remap mwheel-scroll] #'follow-mwheel-scroll) mainmap) "Minor mode keymap for Follow mode.") @@ -343,7 +341,7 @@ property `follow-mode-use-cache' to non-nil.") ;; Internal variables: (defvar follow-internal-force-redisplay nil - "True when Follow mode should redisplay the windows.") + "Non-nil when Follow mode should redisplay the windows.") (defvar follow-active-menu nil "The menu visible when Follow mode is active.") @@ -370,7 +368,7 @@ This is typically set by explicit scrolling commands.") (defsubst follow-debug-message (&rest args) "Like `message', but only active when `follow-debug' is non-nil." (if (and (boundp 'follow-debug) follow-debug) - (apply 'message args))) + (apply #'message args))) ;;; Cache @@ -1020,8 +1018,8 @@ returned by `follow-windows-start-end'." (setq win-start-end (cdr win-start-end))) result)) -;; Check if point is visible in all windows. (So that -;; no one will be recentered.) +;; Check if point is visible in all windows. +;; (So that no one will be recentered.) (defun follow-point-visible-all-windows-p (win-start-end) "Non-nil when the `window-point' is visible in all windows." @@ -1070,11 +1068,11 @@ Return the selected window." win)) ;; Lets select a window showing the end. Make sure we only select it if -;; it wasn't just moved here. (I.e. M-> shall not unconditionally place +;; it wasn't just moved here. (I.e. M-> shall not unconditionally place ;; point in the selected window.) ;; ;; (Compatibility kludge: in Emacs `window-end' is equal to `point-max'; -;; in XEmacs, it is equal to `point-max + 1'. Should I really bother +;; in XEmacs, it is equal to `point-max + 1'. Should I really bother ;; checking `window-end' now when I check `end-of-buffer' explicitly?) (defun follow-select-if-end-visible (win-start-end) @@ -1098,7 +1096,7 @@ Return the selected window." ;; Select a window that will display point if the windows would -;; be redisplayed with the first window fixed. This is useful for +;; be redisplayed with the first window fixed. This is useful for ;; example when the user has pressed return at the bottom of a window ;; as point is not visible in any window. @@ -1203,7 +1201,7 @@ should be a member of WINDOWS, starts at position START." (goto-char guess) (while (not done) (if (not (= (vertical-motion 1 (car windows)) 1)) - ;; Hit bottom! (Can we really do this?) + ;; Hit bottom! (Can we really do this?) ;; We'll keep it, since it ensures termination. (progn (setq done t) @@ -1284,7 +1282,7 @@ non-first windows in Follow mode." (defvar follow-prev-buffer nil "The buffer current at the last call to `follow-adjust-window' or nil. -follow-mode is not necessarily enabled in this buffer.") +`follow-mode' is not necessarily enabled in this buffer.") ;; This function is added to `pre-display-function' and is thus called ;; before each redisplay operation. It supersedes (2018-09) the @@ -1332,7 +1330,7 @@ follow-mode is not necessarily enabled in this buffer.") ;; . (defun follow-adjust-window (win) - ;; Adjust the window WIN and its followers. + "Adjust the window WIN and its followers." (cl-assert (eq (window-buffer win) (current-buffer))) ;; Have we moved out of or into a follow-mode window group? @@ -1647,17 +1645,17 @@ This is updated by redisplay or by calling (defun follow-window-end (&optional window update) "Return position at which display currently ends in the Follow - Mode group of windows which includes WINDOW. +Mode group of windows which includes WINDOW. - WINDOW must be a live window and defaults to the selected one. - This is updated by redisplay, when it runs to completion. - Simply changing the buffer text or setting `window-start' does - not update this value. - - Return nil if there is no recorded value. (This can happen if - the last redisplay of WINDOW was preempted, and did not - finish.) If UPDATE is non-nil, compute the up-to-date position - if it isn't already recorded." +WINDOW must be a live window and defaults to the selected one. +This is updated by redisplay, when it runs to completion. +Simply changing the buffer text or setting `window-start' does +not update this value. + +Return nil if there is no recorded value. (This can happen if +the last redisplay of WINDOW was preempted, and did not +finish.) If UPDATE is non-nil, compute the up-to-date position +if it isn't already recorded." (let* ((windows (follow-all-followers window)) (last (car (last windows)))) (when (and update follow-start-end-invalid) @@ -1677,7 +1675,7 @@ overriding motion of point in order to display at this exact start." (defun follow-pos-visible-in-window-p (&optional pos window partially) "Return non-nil if position POS is currently on the frame in one of - the windows in the Follow Mode group which includes WINDOW. +the windows in the Follow Mode group which includes WINDOW. WINDOW must be a live window and defaults to the selected one. @@ -1696,8 +1694,7 @@ omitted if the character after POS is fully visible; otherwise, RTOP and RBOT are the number of pixels off-window at the top and bottom of the screen line (\"row\") containing POS, ROWH is the visible height of that row, and VPOS is the row number \(zero-based)." - (let* ((windows (follow-all-followers window)) - (last (car (last windows)))) + (let* ((windows (follow-all-followers window))) (when follow-start-end-invalid (follow-redisplay windows (car windows))) (let* ((cache (follow-windows-start-end windows)) @@ -1725,7 +1722,7 @@ zero means top of the first window in the group, negative means (start-end (follow-windows-start-end windows)) (rev-start-end (reverse start-end)) (lines 0) - middle-window elt count) + elt count) (select-window (cond ((null arg) |