TextMate
EmacsKeybindings

In OS X, various keystrokes move the cursor around in exactly the same way as they do in the text editor emacs. For example, in both emacs and TextEdit.app, C-f (control-f) moves the cursor forward one character. (Many emacs-like keybindings are set up by default; you can get access to a few more by copying this DefaultKeyBinding.dict in ~/Library/KeyBindings.)

Unfortunately, some key combinations—though they work in other Cocoa apps—do not work in TextMate. (This is mostly because TextMate binds other commands to the relevant key combinations.) This page: (1) explains how to get TextMate to behave more like emacs; and (2) records the emacs commands that are not supported by TextMate (focusing on those commands that are available to other Cocoa apps).

How emacs behaves : this is what we’re aiming for. (This appear to be a link to an illegal copy of some O’Reilly material; a link to something similar, but legal, would be better!)

Emacs-like commands that are bindable in other Cocoa apps (tested: Mail.app, TextEdit.app, SubEthaEdit.app), but not TextMate:

setMark (C-@, C-SPACE)
deleteToMark (C-w)
yank (C-y)
moveForward¹ (C-f)
deleteForward² (C-d)

(Names taken from Apple’s NSResponder documentation.)

¹ In TextMate, C-f is bound to reformatText; if you bind this to something else (e.g. M-q, emacs’ default—do this by editing /Applications/TextMate.app/Contents/Resources/KeyBindings.dict), C-f will revert to being moveForward.

² In TextMate, C-d duplicates the current line. This is a preset macro “Duplicate Line”—edit the macro to erase (or reassign) this binding (via Automation | Replay Macros | Edit Macros…), and C-d will revert to delete forward.

Emacs-like commands that don’t work quite right in TextMate:

deleteToEndOfLine (C-k)—this doesn’t delete the line if the line happens to be empty.

Emacs-like commands that are unavailable in OS X, but nice to have in TextMate:

isearch-forward (C-s)—incremental search
isearch-backward (C-r)—incremental search
spell-word (M-$)—checks spelling of word under cursor
split-window-horizontally (C-x 2)—(or some other way to get two views of the same file)
delete-other-windows (C-x 1)
backward-paragraph (M-[)
forward-paragraph (M-])
switch-to-buffer (C-x b)—Default switches to last open buffer (see request for history list)
advertised-undo (C-x u or C-)—this is basically just the regular undo, but I don’t see how to bind this to C- in Cocoa; there doesn’t seem to be an “undo” command.

(Names are emacs commands .)