Appendix E Emacs 23 Antinews

For those users who live backwards in time, here is information about downgrading to Emacs version 23.4. We hope you will enjoy the greater simplicity that results from the absence of many Emacs 24.5 features.

• Support for displaying and editing “bidirectional” text has been removed. Text is now always displayed on the screen in a single consistent direction—left to right—regardless of the underlying script. Similarly, C-f and C-b always move the text cursor to the right and left respectively. Also, RIGHT and LEFT are now equivalent to C-f and C-b, as you might expect, rather than moving forward or backward based on the underlying “paragraph direction”.

  Users of “right-to-left” languages, like Arabic and Hebrew, may adapt by reading and/or editing text in left-to-right order.

• The Emacs Lisp package manager has been removed. Instead of using a “user interface” (M-x list-packages), additional Lisp packages must now be installed by hand, which is the most flexible and “Lispy” method anyway. Typically, this just involves editing your init file to add the package installation directory to the load path and defining some autoloads; see each package’s commentary section and/or README file for details.
• The option delete-active-region has been deleted. When the region is active, typing DEL or Delete no longer deletes the text in the region; it deletes a single character instead.
• We have reworked how Emacs handles the clipboard and the X primary selection. Commands for killing and yanking, like C-w and C-y, use the primary selection and not the clipboard, so you can use these commands without interfering with “cutting” or “pasting” in other programs. The ‘Cut’/‘Copy’/‘Paste’ menu items are bound to separate clipboard commands, not to the same commands as C-w/M-w/C-y.

  Selecting text by dragging with the mouse now puts the text in the kill ring, in addition to the primary selection. But note that selecting an active region with C-SPC does not alter the kill ring nor the primary selection, even though the text highlighting is visually identical.

• In Isearch, C-y and M-y are no longer bound to isearch-yank-kill and isearch-yank-pop respectively. Instead, C-y yanks the rest of the current line into the search string (isearch-yank-line), whereas M-y does isearch-yank-kill. The mismatch with the usual meanings of C-y and M-y is unintended.
• Various completion features have been simplified. The option completion-category-overrides has been removed, so Emacs uses a single consistent scheme to generate completions, instead of using a separate scheme for (say) buffer name completion. Several major modes, such as Shell mode, now implement their own inline completion commands instead of using completion-at-point.
• We have removed several options for controlling how windows are used, such as display-buffer-base-action, display-buffer-alist, window-combination-limit, and window-combination-resize.
• The command M-x customize-themes has been removed. Emacs no longer comes with pre-defined themes (you can write your own).
• Emacs no longer adapts various aspects of its display to GTK+ settings, opting instead for a uniform toolkit-independent look. GTK+ scroll bars are placed on the left, the same position as non-GTK+ X scroll bars. Emacs no longer refers to GTK+ to set the default region face, nor for drawing tooltips.
• Setting the option delete-by-moving-to-trash to a non-nil value now causes all file deletions to use the system trash, even temporary files created by Lisp programs; furthermore, the M-x delete-file and M-x delete-directory commands no longer accept prefix arguments to force true deletion.
• On GNU/Linux and Unix, the default method for sending mail (as specified by send-mail-function) is to use the sendmail program. Emacs no longer asks for a delivery method the first time you try to send mail, trusting instead that the system is configured for mail delivery, as it ought to be.
• Several VC features have been removed, including the C-x v + and C-x v m commands for pulling and merging on distributed version control systems, and the ability to view inline log entries in the log buffers made by C-x v L.
• To keep up with decreasing computer memory capacity and disk space, many other functions and files have been eliminated in Emacs 23.4.