Comment/Uncomment in C files?

Comment/Uncomment in C files?

[saneman]

I use emacs22 and have enabled CUA mode. I have assigned 
Comment/Uncomment to:


;; Toogle comment/uncomment
(global-set-key "\C-d" 'comment-dwim)

But nothing happens when I press C-d. Does emacs C-mode use some other 
config files?

Re: Comment/Uncomment in C files?

[Lennart Borgman (gmail)]

saneman wrote:
> I use emacs22 and have enabled CUA mode. I have assigned 
> Comment/Uncomment to:
> 
> 
> ;; Toogle comment/uncomment
> (global-set-key "\C-d" 'comment-dwim)
> 
> But nothing happens when I press C-d. Does emacs C-mode use some other 
> config files?

You can use C-h k or C-h c to find out what a key actually is bound to. 
Maybe that can help you find out what is happening.

Re: Comment/Uncomment in C files?

[Alan Mackenzie]

On Sat, Apr 19, 2008 at 11:06:38AM +0200, saneman wrote:
> I use emacs22 and have enabled CUA mode. I have assigned 
> Comment/Uncomment to:


> ;; Toogle comment/uncomment
> (global-set-key "\C-d" 'comment-dwim)

Quick question: why do you want to do this?  comment-dwim has M-; as a
standard key binding, which is surely just as easy to type, and just as
(un)intuitive ;-).

However, if you just want to do this for no particular reason, .....

> But nothing happens when I press C-d. Does emacs C-mode use some other 
> config files?

C Mode itself binds C-d to c-electric-delete-forward.  More to the point,
it binds it in the keymap c-mode-base-map, and this keymap takes
precedence over the global keymap.  So, if you want your global key
binding to be seen, you'll have to suppress the local keybinding.
Something like this (untested) should work:

(define-key c-mode-base-map "\C-d" nil)

That is, if you _really_ want to do it.

-- 
Alan Mackenzie (Nuremberg, Germany).

Re: Comment/Uncomment in C files?

[saneman]

> (define-key c-mode-base-map "\C-d" nil)

Above gives an error:



An error has occurred while loading `/home/mm/.emacs':

Symbol's value as variable is void: c-mode-base-map

Re: Comment/Uncomment in C files?

[saneman]

saneman wrote:
> 
>> (define-key c-mode-base-map "\C-d" nil)
> 
> Above gives an error:
> 
> 
> 
> An error has occurred while loading `/home/mm/.emacs':
> 
> Symbol's value as variable is void: c-mode-base-map

This did the trick:

  (define-key c-mode-base-map "\C-d" 'comment-dwim)

Re: Comment/Uncomment in C files?

[Alan Mackenzie]

Hi, Saneman!

On Sat, Apr 19, 2008 at 01:02:07PM +0200, saneman wrote:
> saneman wrote:

> >>(define-key c-mode-base-map "\C-d" nil)

> >Above gives an error:

> >An error has occurred while loading `/home/mm/.emacs':

> >Symbol's value as variable is void: c-mode-base-map

Whoops, sorry!  What happened there was that CC Mode hadn't been loaded
when you tried to execute the `define-key'.

> This did the trick:

>  (define-key c-mode-base-map "\C-d" 'comment-dwim)

That will suffer exactly the same problem.  What you need is

    (defun sm-C-d ()
      (define-key c-mode-base-map "\C-d" 'comment-dwim)) ; or nil
    (add-hook 'c-initialization-hook 'sm-C-d)

, fairly early on in your .emacs.  That will cause the key to rebound
when CC Mode later gets loaded.

-- 
Alan Mackenzie (Nuremberg, Germany).

Re: Comment/Uncomment in C files?

[Joost Kremers]

Alan Mackenzie wrote:
>     (defun sm-C-d ()
>       (define-key c-mode-base-map "\C-d" 'comment-dwim)) ; or nil
>     (add-hook 'c-initialization-hook 'sm-C-d)

no need to use a defun for that:

(add-hook 'c-initialization-hook #'(lambda ()
				     (define-key c-mode-base-map "\C-d" 'comment-dwim)

works just as well.


-- 
Joost Kremers                                      joostkremers@yahoo.com
Selbst in die Unterwelt dringt durch Spalten Licht
EN:SiS(9)

Re: Comment/Uncomment in C files?

[David Hansen]

On 20 Apr 2008 11:48:13 GMT Joost Kremers wrote:

> Alan Mackenzie wrote:
>>     (defun sm-C-d ()
>>       (define-key c-mode-base-map "\C-d" 'comment-dwim)) ; or nil
>>     (add-hook 'c-initialization-hook 'sm-C-d)
>
> no need to use a defun for that:
>
> (add-hook 'c-initialization-hook #'(lambda ()
> 				     (define-key c-mode-base-map "\C-d" 'comment-dwim)
>
> works just as well.

But it's way more complicated to `remove-hook' it now.

David

Re: Comment/Uncomment in C files?

[David Hansen]

On Sat, 19 Apr 2008 11:06:38 +0200 saneman wrote:

> I use emacs22 and have enabled CUA mode. I have assigned
> Comment/Uncomment to:
>
>
> ;; Toogle comment/uncomment
> (global-set-key "\C-d" 'comment-dwim)
>
> But nothing happens when I press C-d. Does emacs C-mode use some other
> config files?

What's wrong with the standard M-;?  Overwriting an essential command
like `delete-char' doesn't seem wise to me.

David