Binding C-i without losing <tab> functionality

Binding C-i without losing <tab> functionality

[Joseph Peterson]

Hello all,

I'm trying to bind C-i to isearch-forward, but I'm having some problems.  

It doesn't change anything when I do this or variations of this: 
  (global-set-key [?\C-i] 'isearch-forward)

Sometimes it seems like it will work, but it rebinds the tab key, too 
(I may be remembering when I bound TAB, though...)

If I bind both <tab> and C-i, then it seems that I can rebind C-i to be
different than <tab>. Like this:
  (global-set-key [tab] 'c-indent-command)
  (global-set-key [?\C-i] 'isearch-forward)

Then it seems to work, but then I lose all the mode-specific bindings. 
(Most annoying is the loss of mini-buffer completion). How do I bind 
C-i without affecting the Tab key?

Thanks all,
-JEEP
Joe Peterson


      

Re: Binding C-i without losing <tab> functionality

[Paul R]

On Thu, 23 Oct 2008 17:56:03 -0700 (PDT), Joseph Peterson <jeepeterson@yahoo.com> said:

Joseph> Hello all, I'm trying to bind C-i to isearch-forward, but I'm
Joseph> having some problems.

Some devices are known to treat C-i and TAB as the same signal, as
well as C-m and RET. I think this is why it is not so easy to
dissociate them in emacs, even when your device allows it.

-- 
  Paul

Re: Binding C-i without losing <tab> functionality

[Andreas Politz]

Paul R wrote:
> On Thu, 23 Oct 2008 17:56:03 -0700 (PDT), Joseph Peterson <jeepeterson@yahoo.com> said:
> 
> Joseph> Hello all, I'm trying to bind C-i to isearch-forward, but I'm
> Joseph> having some problems.
> 
> Some devices are known to treat C-i and TAB as the same signal, as
> well as C-m and RET. I think this is why it is not so easy to
> dissociate them in emacs, even when your device allows it.
> 

This looks like the answer :


,----[ (info "(elisp)Function Keys") ]
|      In ASCII, `C-i' and <TAB> are the same character.  If the terminal
|      can distinguish between them, Emacs conveys the distinction to
|      Lisp programs by representing the former as the integer 9, and the
|      latter as the symbol `tab'.
|
|      Most of the time, it's not useful to distinguish the two.  So
|      normally `function-key-map' (*note Translation Keymaps::) is set
|      up to map `tab' into 9.  Thus, a key binding for character code 9
|      (the character `C-i') also applies to `tab'.  Likewise for the
|      other symbols in this group.  The function `read-char' likewise
|      converts these events into characters.
`----

(member '(tab . [9]) function-keymap)

-ap

Re: Binding C-i without losing <tab> functionality

[jeep]

On Oct 24, 2:30 am, Andreas Politz <poli...@fh-trier.de> wrote:
> (member '(tab . [9]) function-keymap)

Would you mind explaining this a little? I cannot evaluate that in
emacs. And I don't understand what it's supposed to do.

Thanks,
-JEEP

Re: Binding C-i without losing <tab> functionality

[Andreas Politz]

jeep wrote:
> On Oct 24, 2:30 am, Andreas Politz <poli...@fh-trier.de> wrote:
>> (member '(tab . [9]) function-keymap)
> 
> Would you mind explaining this a little? I cannot evaluate that in
> emacs. And I don't understand what it's supposed to do.
> 
> Thanks,
> -JEEP

I forgot a hyphen. The thing is called `function-key-map'.

(member '(tab . [9]) function-key-map)

After reading the mentioned info page (what you should have done as well)
, I would do it like so:

1. Don't translate tab into C-i.
(define-key function-key-map [tab] nil)

2. Swap the meanings of tab and C-i.
(define-key key-translation-map [9] [tab])
(define-key key-translation-map [tab] [9])

3. Bind tab (which is now actually C-i)
(global-set-key [tab] 'isearch-forward)

Note that I am an emacs newbie as well, so I can't tell what
sideeffects this has. But it seems to work. Unless the system
can't differentiate this 2 keys, like in an xterm.

-ap

Re: Binding C-i without losing <tab> functionality

[jeep]

Thank you! That seems to work. I'll post again if I find any weird
side effects.

> After reading the mentioned info page (what you should have done as well)

In my defense, I did read the info page... I just didn't understand
it. *blush*
I should have mentioned that, I guess.

Thanks,
-JEEP

Re: Binding C-i without losing <tab> functionality

[jeep]

> 1. Don't translate tab into C-i.
> (define-key function-key-map [tab] nil)
> 2. Swap the meanings of tab and C-i.
> (define-key key-translation-map [9] [tab])
> (define-key key-translation-map [tab] [9])
> 3. Bind tab (which is now actually C-i)
> (global-set-key [tab] 'isearch-forward)

I really do appreciate the help and I'm sorry that I'm being a bit
dense, but I want to understand this.

This works for what I want to do, but I still don't grok it. I
understand all the steps, but now... if I want to reassign the tab
key, how would I go about doing that? Everything I try seems to fail,
just like it did before for C-i. I've been reading info for hours now
and I understand a lot more about emacs, but this still bothers me.

Thanks a lot.
-JEEP

Re: Binding C-i without losing <tab> functionality

[Andreas Politz]

jeep wrote:
>> 1. Don't translate tab into C-i.
>> (define-key function-key-map [tab] nil)
>> 2. Swap the meanings of tab and C-i.
>> (define-key key-translation-map [9] [tab])
>> (define-key key-translation-map [tab] [9])
>> 3. Bind tab (which is now actually C-i)
>> (global-set-key [tab] 'isearch-forward)
> 
> I really do appreciate the help and I'm sorry that I'm being a bit
> dense, but I want to understand this.
> 
> This works for what I want to do, but I still don't grok it. I
> understand all the steps, but now... if I want to reassign the tab
> key, how would I go about doing that? Everything I try seems to fail,
> just like it did before for C-i. I've been reading info for hours now
> and I understand a lot more about emacs, but this still bothers me.
> 
> Thanks a lot.
> -JEEP

What are you doing and what doesn't work ?

-ap

Re: Binding C-i without losing <tab> functionality

[jeep]

On Oct 25, 3:02 am, Andreas Politz <poli...@fh-trier.de> wrote:
> jeep wrote:
> >> 1. Don't translate tab into C-i.
> >> (define-key function-key-map [tab] nil)
> >> 2. Swap the meanings of tab and C-i.
> >> (define-key key-translation-map [9] [tab])
> >> (define-key key-translation-map [tab] [9])
> >> 3. Bind tab (which is now actually C-i)
> >> (global-set-key [tab] 'isearch-forward)
>
> > I really do appreciate the help and I'm sorry that I'm being a bit
> > dense, but I want to understand this.
>
> > This works for what I want to do, but I still don't grok it. I
> > understand all the steps, but now... if I want to reassign the tab
> > key, how would I go about doing that? Everything I try seems to fail,
> > just like it did before for C-i. I've been reading info for hours now
> > and I understand a lot more about emacs, but this still bothers me.
>
> > Thanks a lot.
> > -JEEP
>
> What are you doing and what doesn't work ?
>
> -ap

Sorry, I don't recall what I was doing wrong, but I managed to figure
it out. I guess I just needed a day to let things soak in.

Thanks!
-JEEP

Re: Binding C-i without losing <tab> functionality

[jeep]

> Some devices are known to treat C-i and TAB as the same signal, as
> well as C-m and RET. I think this is why it is not so easy to
> dissociate them in emacs, even when your device allows it.

I can disassociate them... if I set them both. My understanding is
that
C-i and <tab> are both, by default, set to ASCII character 9, which is
given the notation TAB.

If I set both "C-i" and "<tab>", then C-i and the tab key do different
things.
Unfortunately, many modes bind the tab key differently. I want to keep
all those other bindings while reassigning C-i.

It's the same thing with <return> and C-m. They are both aliased to
RET (ASCII 13).  But the following code works fine:
  (global-set-key [return] 'newline)
  (global-set-key [?\C-m] 'open-line)

I don't know how to make one different than the other without binding
them both. The <tab> is so useful, I don't want to globally rebind it.
I only want C-i rebound.

-JEEP

Re: Binding C-i without losing <tab> functionality

[Xah]

On Oct 23, 5:56 pm, Joseph Peterson <jeepeter...@yahoo.com> wrote:
> Hello all,
>
> I'm trying to bind C-i to isearch-forward, but I'm having some problems.
>
> It doesn't change anything when I do this or variations of this:
>   (global-set-key [?\C-i] 'isearch-forward)
>
> Sometimes it seems like it will work, but it rebinds the tab key, too
> (I may be remembering when I bound TAB, though...)
>
> If I bind both <tab> and C-i, then it seems that I can rebind C-i to be
> different than <tab>. Like this:
>   (global-set-key [tab] 'c-indent-command)
>   (global-set-key [?\C-i] 'isearch-forward)
>
> Then it seems to work, but then I lose all the mode-specific bindings.
> (Most annoying is the loss of mini-buffer completion). How do I bind
> C-i without affecting the Tab key?

not sure if you can. Because i think internally Ctrl+i and Tab are
both rerpresented by ascii 9. (ascii 9 is named Horizontal Tab with
standard notation ^I)

similar other pairs i noticed are Return and Ctrl+m (which is ascii
13; ^M).

i might be wrong though.

Reference:
http://xahlee.org/elisp/Character-Type.html

quote: «
 Control characters may be represented using yet another read syntax.
This consists of a question mark followed by a backslash, caret, and
the corresponding non-control character, in either upper or lower
case. For example, both `?\^I' and `?\^i' are valid read syntax for
the character C-i, the character whose value is 9.

Instead of the `^', you can use “C-”; thus, `?\C-i' is equivalent to `?
\^I' and to `?\^i':

     ?\^I ⇒ 9     ?\C-I ⇒ 9
»

  Xah
∑ http://xahlee.org/

☄