bug#553: 23.0.60; Unknown button type `quail-keyboard-layout-button'

bug#553: 23.0.60; Unknown button type `quail-keyboard-layout-button'

[Juri Linkov]

1. `emacs -Q'
2. `M-: (require 'help-mode) RET'
   or run any Help command that loads this mode
3. Activate an input method by C-\
4. Click `mouse-3' on the input method's indicator
   on the mode-line

It fills the *Help* buffer with the text only until
it tries to create a button, and fails with the error
"make-text-button: Unknown button type `quail-keyboard-layout-button'".

This is because `quail-help-init' fails to define new button types.
It currently has the form:

(defun quail-help-init ()
  (unless (featurep 'help-mode)
    (require 'help-mode)
    (define-button-type 'quail-keyboard-layout-button
      :supertype 'help-xref
      'help-function '(lambda (layout)
			(help-setup-xref `(quail-keyboard-layout-button ,layout)
					 nil)
			(quail-show-keyboard-layout layout))
      'help-echo (purecopy "mouse-2, RET: show keyboard layout"))

    (define-button-type 'quail-keyboard-customize-button
      :supertype 'help-customize-variable
      'help-echo (purecopy "mouse-2, RET: customize keyboard layout"))))

So it doesn't define two button types if `help-mode' is already loaded.

I guess it was done to define them only once, and not redefine on next
invocations.  Instead of checking for (featurep 'help-mode) it could
check if these buttons were already defined.  I can't find a function
like `button-defined-p' to do this.  But the following check seems to work:

(get 'quail-keyboard-layout-button 'button-category-symbol)

-- 
Juri Linkov
http://www.jurta.org/emacs/

bug#553: marked as done (23.0.60; Unknown button type `quail-keyboard-layout-button')

[Emacs bug Tracking System]

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Your message dated Fri, 05 Sep 2008 18:15:22 -0400
with message-id <871vzyjl39.fsf@cyd.mit.edu>
and subject line Re: 23.0.60; Unknown button type `quail-keyboard-layout-button'
has caused the Emacs bug report #553,
regarding 23.0.60; Unknown button type `quail-keyboard-layout-button'
to be marked as done.

This means that you claim that the problem has been dealt with.
If this is not the case it is now your responsibility to reopen the
bug report if necessary, and/or fix the problem forthwith.

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-- 
553: http://emacsbugs.donarmstrong.com/cgi-bin/bugreport.cgi?bug=553
Emacs Bug Tracking System
Contact don@donarmstrong.com with problems

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From: Juri Linkov <juri@jurta.org>
To: emacs-pretest-bug@gnu.org
Subject: 23.0.60; Unknown button type `quail-keyboard-layout-button'
Date: Sun, 13 Jul 2008 01:04:42 +0300
Message-ID: <87d4likbd1.fsf@jurta.org>

1. `emacs -Q'
2. `M-: (require 'help-mode) RET'
   or run any Help command that loads this mode
3. Activate an input method by C-\
4. Click `mouse-3' on the input method's indicator
   on the mode-line

It fills the *Help* buffer with the text only until
it tries to create a button, and fails with the error
"make-text-button: Unknown button type `quail-keyboard-layout-button'".

This is because `quail-help-init' fails to define new button types.
It currently has the form:

(defun quail-help-init ()
  (unless (featurep 'help-mode)
    (require 'help-mode)
    (define-button-type 'quail-keyboard-layout-button
      :supertype 'help-xref
      'help-function '(lambda (layout)
			(help-setup-xref `(quail-keyboard-layout-button ,layout)
					 nil)
			(quail-show-keyboard-layout layout))
      'help-echo (purecopy "mouse-2, RET: show keyboard layout"))

    (define-button-type 'quail-keyboard-customize-button
      :supertype 'help-customize-variable
      'help-echo (purecopy "mouse-2, RET: customize keyboard layout"))))

So it doesn't define two button types if `help-mode' is already loaded.

I guess it was done to define them only once, and not redefine on next
invocations.  Instead of checking for (featurep 'help-mode) it could
check if these buttons were already defined.  I can't find a function
like `button-defined-p' to do this.  But the following check seems to work:

(get 'quail-keyboard-layout-button 'button-category-symbol)

-- 
Juri Linkov
http://www.jurta.org/emacs/



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From: Chong Yidong <cyd@stupidchicken.com>
To: Juri Linkov <juri@jurta.org>
Cc: 553-done@emacsbugs.donarmstrong.com
Subject: Re: 23.0.60; Unknown button type `quail-keyboard-layout-button'
Date: Fri, 05 Sep 2008 18:15:22 -0400
Message-ID: <871vzyjl39.fsf@cyd.mit.edu>

> I don't know the reason of writing quail-help-init this way, but it
> seems it was to not load `help-mode' after loading `quail.el'.
> `help-mode' is not necessary for quail's operations, so its loading
> should be postponed for rare cases when the user needs to see the help
> buffer with keyboard layouts.

I don't think it's a big deal to just load help-mode, so I changed
quail.el to do that.

bug#553: 23.0.60; Unknown button type `quail-keyboard-layout-button'

[Chong Yidong]

Hi Handa-san,

> 1. `emacs -Q'
> 2. `M-: (require 'help-mode) RET'
>    or run any Help command that loads this mode
> 3. Activate an input method by C-\
> 4. Click `mouse-3' on the input method's indicator
>    on the mode-line
>
> It fills the *Help* buffer with the text only until
> it tries to create a button, and fails with the error
> "make-text-button: Unknown button type `quail-keyboard-layout-button'".
>
> This is because `quail-help-init' fails to define new button types.
> It currently has the form:
>
> (defun quail-help-init ()
>   (unless (featurep 'help-mode)
>     (require 'help-mode)
>     (define-button-type 'quail-keyboard-layout-button
>       :supertype 'help-xref
>       'help-function '(lambda (layout)
> 			(help-setup-xref `(quail-keyboard-layout-button ,layout)
> 					 nil)
> 			(quail-show-keyboard-layout layout))
>       'help-echo (purecopy "mouse-2, RET: show keyboard layout"))
>
>     (define-button-type 'quail-keyboard-customize-button
>       :supertype 'help-customize-variable
>       'help-echo (purecopy "mouse-2, RET: customize keyboard layout"))))
>
> So it doesn't define two button types if `help-mode' is already loaded.
>
> I guess it was done to define them only once, and not redefine on next
> invocations.

Do you remember why you wrote quail-help-init this way?  It seems
unnecessary; why not define the button types directly at the top level
of quail.el?

bug#553: 23.0.60; Unknown button type `quail-keyboard-layout-button'

[Juri Linkov]

> Do you remember why you wrote quail-help-init this way?  It seems
> unnecessary; why not define the button types directly at the top level
> of quail.el?

I don't know the reason of writing quail-help-init this way, but it seems
it was to not load `help-mode' after loading `quail.el'.  `help-mode' is
not necessary for quail's operations, so its loading should be postponed
for rare cases when the user needs to see the help buffer with keyboard
layouts.

-- 
Juri Linkov
http://www.jurta.org/emacs/

bug#553: 23.0.60; Unknown button type `quail-keyboard-layout-button'

[Chong Yidong]

> > Do you remember why you wrote quail-help-init this way?  It seems
> > unnecessary; why not define the button types directly at the top level
> > of quail.el?
>
> I don't know the reason of writing quail-help-init this way, but it seems
> it was to not load `help-mode' after loading `quail.el'.  `help-mode' is
> not necessary for quail's operations, so its loading should be postponed
> for rare cases when the user needs to see the help buffer with keyboard
> layouts.

Right, but why do we have to put the button definitions inside
quail-help-init?  In other words, why not the following?

*** trunk/lisp/international/quail.el.~1.164.~	2008-05-06 00:18:15.000000000 -0400
--- trunk/lisp/international/quail.el	2008-08-26 17:09:39.000000000 -0400
***************
*** 2424,2450 ****
  	(insert ?\n))
        (insert ?\n))))
  
! (defun quail-help-init ()
!   (unless (featurep 'help-mode)
!     (require 'help-mode)
!     (define-button-type 'quail-keyboard-layout-button
!       :supertype 'help-xref
!       'help-function '(lambda (layout)
! 			(help-setup-xref `(quail-keyboard-layout-button ,layout)
! 					 nil)
! 			(quail-show-keyboard-layout layout))
!       'help-echo (purecopy "mouse-2, RET: show keyboard layout"))
! 
!     (define-button-type 'quail-keyboard-customize-button
!       :supertype 'help-customize-variable
!       'help-echo (purecopy "mouse-2, RET: customize keyboard layout"))))
  
  (defun quail-help (&optional package)
    "Show brief description of the current Quail package.
  Optional arg PACKAGE specifies the name of alternative Quail
  package to describe."
    (interactive)
!   (quail-help-init)
    (let ((help-xref-mule-regexp help-xref-mule-regexp-template)
  	(mb enable-multibyte-characters)
  	(package-def
--- 2424,2447 ----
  	(insert ?\n))
        (insert ?\n))))
  
! (define-button-type 'quail-keyboard-layout-button
!   :supertype 'help-xref
!   'help-function '(lambda (layout)
! 		    (help-setup-xref `(quail-keyboard-layout-button ,layout)
! 				     nil)
! 		    (quail-show-keyboard-layout layout))
!   'help-echo (purecopy "mouse-2, RET: show keyboard layout"))
! 
! (define-button-type 'quail-keyboard-customize-button
!   :supertype 'help-customize-variable
!   'help-echo (purecopy "mouse-2, RET: customize keyboard layout"))
  
  (defun quail-help (&optional package)
    "Show brief description of the current Quail package.
  Optional arg PACKAGE specifies the name of alternative Quail
  package to describe."
    (interactive)
!   (require 'help-mode)
    (let ((help-xref-mule-regexp help-xref-mule-regexp-template)
  	(mb enable-multibyte-characters)
  	(package-def