bug#20904: If global-set-key is used to rebind <tab>, searching for a TAB character inserts a TAB

bug#20904: If global-set-key is used to rebind <tab>, searching for a TAB character inserts a TAB

[Fran Litterio]

This happens in Emacs built from the latest sources on Windows 7.
To reproduce:

  1. Launch Emacs with: runemacs.exe -Q
  
  2. Type "C-s TAB".  See the error "Failing I-search: ^I" in
     the minibuffer.  This is expected.
  
  2. Evaluate this form:
  
     (global-set-key (kbd "<tab>") 'tab-to-tab-stop)
  
  3. Type "C-s TAB".  Instead of searching for a TAB character, this
     inserts a TAB character.
--
Fran Litterio
flitterio@gmail.com


In GNU Emacs 25.0.50.1 (i686-pc-mingw32)
 of 2015-06-23 on IZSYSTEM023
Repository revision: 931f00677dee11d687b99140d25e5373448e329c
Windowing system distributor `Microsoft Corp.', version 6.1.7601
Configured using:
 `configure --prefix=c:/apps/emacs --without-x --without-xpm
 --without-png --without-jpeg --without-tiff --without-gif'

Configured features:
SOUND NOTIFY ACL TOOLKIT_SCROLL_BARS

Important settings:
  value of $LANG: C.ISO-8859-1
  locale-coding-system: cp1252

Major mode: Lisp Interaction

Minor modes in effect:
  tooltip-mode: t
  global-eldoc-mode: t
  electric-indent-mode: t
  mouse-wheel-mode: t
  tool-bar-mode: t
  menu-bar-mode: t
  file-name-shadow-mode: t
  global-font-lock-mode: t
  font-lock-mode: t
  blink-cursor-mode: t
  auto-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  line-number-mode: t
  transient-mark-mode: t

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edmacro kmacro cl-loaddefs pcase cl-lib time-date mule-util tooltip
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bug#20904: If global-set-key is used to rebind <tab>, searching for a TAB character inserts a TAB

[Fran Litterio]

I <flitterio <at> gmail.com> wrote:

>   2. Evaluate this form:
> 
>      (global-set-key (kbd "<tab>") 'tab-to-tab-stop)

I have found that changing the above form to:

  (global-set-key (kbd "TAB") 'tab-to-tab-stop)

avoids the problem (i.e., it allows the global binding of TAB to be
changed to tab-to-tab-stop and allows searching for a TAB character).
--
Fran

bug#20904: If global-set-key is used to rebind <tab>, searching for a TAB character inserts a TAB

[Stefan Monnier]

tags 20904 notabug
thanks

>> (global-set-key (kbd "<tab>") 'tab-to-tab-stop)
> I have found that changing the above form to:
>   (global-set-key (kbd "TAB") 'tab-to-tab-stop)
> avoids the problem (i.e., it allows the global binding of TAB to be
> changed to tab-to-tab-stop and allows searching for a TAB character).

That's right.
Most of Emacs (including Isearch) gives no special meaning to `tab', and
instead this key is typically remapped to TAB.
So unless you care about the difference between the two, you should
always bind the TAB and not `tab'.


        Stefan

bug#20904: If global-set-key is used to rebind <tab>, searching for a TAB character inserts a TAB

[Eli Zaretskii]

> From: Fran Litterio <flitterio@gmail.com>
> Date: Fri, 26 Jun 2015 17:00:34 +0000 (UTC)
> 
> I <flitterio <at> gmail.com> wrote:
> 
> >   2. Evaluate this form:
> > 
> >      (global-set-key (kbd "<tab>") 'tab-to-tab-stop)
> 
> I have found that changing the above form to:
> 
>   (global-set-key (kbd "TAB") 'tab-to-tab-stop)
> 
> avoids the problem (i.e., it allows the global binding of TAB to be
> changed to tab-to-tab-stop and allows searching for a TAB character).

That's exactly what you should have done.  <tab> is a function key,
not the character Ctrl-I.