I want my C/M-h keys to be a binding for delete.
The usual solution of global-set-key doesn't work for me, as I want these keys to behave as delete everywhere including the minibuffer and various modes, and be able to work between my various Linux/OS X/Windows emacs installations.
I have the following near solution:
(when (>= emacs-major-version 23)
(setq help-char (string-to-char "<f1>")) ;; Bind ONLY F1 to help, not C-h
(define-key input-decode-map (kbd "C-h") (kbd "DEL")) ;; Translate C-h to DEL ;; FIXME: Should be in emacs 22, doens't work.
(define-key input-decode-map (kbd "M-h") (kbd "M-<DEL>")) ;; Translate M-h to M-DEL
;; (define-key input-decode-map (kbd "<backspace>") 'version) ;; Stop me using backspace for a while
)
But this obviously only works with Emacs > 22, due to input-decode-map.
Would someone be able to help me find a solution that works in 22, maybe even 21? (Not a priority however). Cheers!
Edit: My Solution:
It's not quite there yet, but this has solved most of my issues:
(setq help-char [f1]) ;; I don't want help when I'm just trying to backspace!
(define-key isearch-mode-map "\C-h" 'isearch-delete-char)
;; (define-key isearch-mode-map "\M-h" 'my-isearch-delete-word)
(defvar my-overriding-binding-mode-map
(let ((map (make-sparse-keymap)))
(define-key map [?\C-h] 'delete-backward-char)
(define-key map [?\M-h] 'backward-kill-word)
map))
(define-minor-mode my-overriding-binding-mode
"Personal global key-bindings."
:global t)
(my-overriding-binding-mode 1)
There's probably some caveats for some misbehaving modes that need to be written - I'll do that as I come across them. The only real problem now seems to be M-h in isearch, which I'll post as a seperate question.
Thanks again guys, you've been a great help.
Here's the first, and most important, part of the answer, with the explanations all given in the elisp comments. This has been tested mostly in X11 environments, but including with a Mac keyboard. It has been tested starting with v19.28, and up to and including v23.3. I think it works with v24, but I have not yet used v24 very much.
You can find my complete (though not always 100% up-to-date) ~/.emacs.el in the following repository of initialization and configuration files:
https://github.com/robohack/dotfiles
and so specifically ~/.emacs.el is at:
https://github.com/robohack/dotfiles/blob/master/.emacs.el
;;; first off, we do some fancy stuff to make C-h work "properly," but still
;;; have good access to the help functions!
;;;
;;; Using C-h for "help" might seem OK to some folks, but since it's also the
;;; ASCII standard value for the "backspace" character, one typically used ever
;;; since the days of the typewriter to move the cursor backwards one position
;;; and in computing normally to erase any character backed over, a vast amount
;;; of stupidity is needed in emacs to continue to (ab)use as the "help"
;;; character. Instead it is still quite intuitive, and often much easier in
;;; zillions of environments, to use M-? for help.
;;;
;;; So, we can set C-h and C-? and friends to sensible bindings...
;;
;; Remember to call override-local-key-settings in the appropriate hooks to fix
;; up modes which violate global user preferences....
;;
(global-set-key "\C-h" 'delete-backward-char)
(global-set-key "\C-?" 'delete-char)
(global-set-key "\e\C-h" 'backward-kill-word)
(global-set-key "\e\C-?" 'kill-word)
;;; and then we diddle with help to make it work again....
;;
;; Oddly, the help interface in emacs is extremely scatter-brained, with
;; several slightly different ways of doing the same thing. This is probably
;; due to the fact that several different programmers have implemented various
;; bits and pieces of the help systems. See help.el and help-macro.el, but try
;; not to tear your hair out when you find out help-event-list in 19.34 is
;; essentially bogus, since it is simply an extension to a "standard" list.
;;
;; Remember to call override-local-key-settings in the appropriate hooks to fix
;; up modes which violate global user preferences....
;;
(global-set-key [f1] 'help-command) ; first do this for 19.28.
(global-set-key "\e?" 'help-command) ; this is the first step to set up help
(global-set-key "\e?F" 'view-emacs-FAQ) ; in 19.34 it needs more help...
;; should help-char be just ? instead?
(setq help-char ?\M-?) ; this should "fix" the rest.
;; one more handy help-related binding...
;;
(define-key help-map "?" 'describe-key-briefly) ; also C-x? for Jove compat
;;; Now for function key mappings...
;;;
;;; I USUALLY EXPECT THE BACKSPACE KEY TO WORK LIKE AN ASCII BACKSPACE!
;;
;; For some entirely un-fathomable reason the default function bindings make
;; the 'backspace' and 'delete' keys synonymous!
;;
;; NOTE: this *should* work by simply reading termio for current erase char.
;;
;; As of emacs-21.2 a note was added to the NEWS file which says "** On
;; terminals whose erase-char is ^H (Backspace), Emacs now uses
;; normal-erase-is-backspace-mode." Unfortunately this does EXACTLY the WRONG
;; thing, and in a totally bizzare, disruptive, subversive, and stupid
;; backwards way. With every major release it's gotten worse and worse and
;; worse; more convoluted, and ugly.
;;
;; So, we must do something to kill that horrible stupid broken poor
;; useless excuse for a feature, normal-erase-is-backspace-mode....
;;
;; seems 23.1 changes function-key-map radically....
;;
;; Unfortunately 23.1 also still has function-key-map so we can't make that
;; (function-key-map) an alias for the new local-function-key-map that we need
;; to use in 23.1 to modify key translations. Sigh.
;;
;; Instead make a new alias that can be used transparently as the desired map.
;;
(eval-and-compile
(if (functionp 'defvaralias) ; since 22.1
(if (boundp 'local-function-key-map)
(defvaralias 'my-function-key-map 'local-function-key-map
"Special variable alias to allow transparent override of
`local-function-key-map' for 23.1 vs 22.3(?).")
(defvaralias 'my-function-key-map 'function-key-map
"Special variable alias to allow transparent override
of `function-key-map' for 22.3(?) vs. older,"))
;; XXX is this right? it works (maybe?)
(defvar my-function-key-map function-key-map)))
;;
;; First undo (local-)function-key-map weirdness.
;;
;; luckily on Mac OS-X X11, at least with the mini-wireless keyboard and on the
;; large USB keyboard, the big "delete" key on the main block is actually
;; sending <backspace> by default, else one would have to first change the X11
;; keyboard map!
;;
(define-key my-function-key-map [delete] [?\C-?])
(define-key my-function-key-map [S-delete] [?\C-h])
(define-key my-function-key-map [M-delete] [?\C-\M-?])
(define-key my-function-key-map [kp-delete] [?\C-?])
(define-key my-function-key-map [backspace] [?\C-h])
(define-key my-function-key-map [S-backspace] [?\C-?])
;;(define-key my-function-key-map [C-backspace] [?\C-h]) ; sometimes *is* DEL....
(define-key my-function-key-map [M-backspace] [?\e?\C-h])
(define-key my-function-key-map [M-S-backspace] [?\e?\C-?])
(define-key my-function-key-map [kp-backspace] [?\C-h])
;;
;; Next, zap the keyboard translate table, set up by
;; normal-erase-is-backspace-mode (in simple.el), which can do nothing
;; but confuse!
;;
(setq keyboard-translate-table nil)
;;
;; Finally, kill, Kill, KILL! the input-decode-map added in 23.x, and set
;; up by normal-erase-is-backspace-mode (in simple.el) which can do
;; nothing but confuse!
;;
;; This is TRULY _E_V_I_L_!!!! HORRID!!! MASSIVELY STUPID!!!!
;;
;; input-decode-map is poorly documented, and causes things above and
;; below to fail with the most confusing errors!
;;
;; (This probably only needs to be blown away on window systems, and
;; perhaps only for X, but doing it here now is apparently early enough
;; to allow for terminal mode specific settings to be re-applied to it
;; and so it seems safe to just blow away the asinine stupid attempt to
;; transpose backspace and delete. RMS is a pedantic idiot on this!)
;;
(if (boundp 'input-decode-map)
(setq input-decode-map (make-sparse-keymap)))
;; finally here's a little function to help fix up modes which don't honour default
;; bindings in sensible ways. Use this in any init hooks for modes which cause problems
;;
(defun override-local-key-settings ()
"User defined function. Intended to be called within various hooks to
override the value of buffer-local key map settings which may have been
overridden without consideration by the major mode."
(local-set-key "\C-?" 'delete-char) ; many modes
(local-set-key "\C-h" 'delete-backward-char) ; sh-mode
;; the rest are *not* overridden by cc-mode, but are by c-mode
(local-set-key "\e\C-h" 'backward-kill-word) ; text-mode
(local-set-key "\e?" 'help-command) ; nroff-mode
(local-set-key "\eh" 'mark-c-function)
(local-set-key "\e\C-?" 'kill-word)
(local-set-key "\e\C-e" 'compile)
;; try this on for size...
(local-set-key "\C-x\e\C-e" 'recompile)
)
(add-hook 'isearch-mode-hook
(function
(lambda ()
"Private isearch-mode fix for C-h."
(define-key isearch-mode-map "\C-h" 'isearch-delete-char))))
;;; OK, that's the end of the stuff to fix GNU Emacs' C-h brain damage. Phew!