Re: Re: Support (or not) for Emacs 21, and XEmacs

[Carsten Dominik <carsten.dominik@gmail.com>]

OK.

- Carsten

On Apr 19, 2010, at 5:54 PM, Michael Sperber wrote:

>
> Carsten Dominik <carsten.dominik@gmail.com> writes:
>
>> That is acceptable - but I think that making BUFFER default to
>> (current-buffer) does make a lot of sense - which is why making that
>> argument optional in XEmacs is a good idea anyway.
>
> It would - but the problem is that in XEmacs, an omitted BUFFER  
> argument
> means something different from (current-buffer):
>
> `local-variable-p' is a built-in function
>  -- loaded from "/afs/informatik.uni-tuebingen.de/home/sperber/build/ 
> xemacs/src/symbols.c"
> (local-variable-p SYMBOL BUFFER &optional AFTER-SET)
>
> Documentation:
> Return t if SYMBOL's value is local to BUFFER.
> If optional third arg AFTER-SET is non-nil, return t if SYMBOL would  
> be
> buffer-local after it is set, regardless of whether it is so  
> presently.
> A nil value for BUFFER is *not* the same as (current-buffer), but  
> means
> "no buffer".  Specifically:
>
> -- If BUFFER is nil and AFTER-SET is nil, a return value of t  
> indicates that
>   the variable is one of the special built-in variables that is always
>   buffer-local. (This includes `buffer-file-name', `buffer-read-only',
>   `buffer-undo-list', and others.)
>
> -- If BUFFER is nil and AFTER-SET is t, a return value of t  
> indicates that
>   the variable has had `make-variable-buffer-local' applied to it.
>
> -- 
> Cheers =8-} Mike
> Friede, Völkerverständigung und überhaupt blabla

- Carsten