bug#9571: 24.0.50; user option to turn off bidi, please

["Štěpán Němec" <stepnem@gmail.com>]

On Fri, 23 Sep 2011 11:21:02 +0200
Juanma Barranquero wrote:

> OOH, there was a time when suggesting that the user adds something to
> .emacs, like
>
>   (setq-default bidi-display-reordering nil)
>
> was not considered obscure. Not everything must go through the
> customization interface.

It's certainly good enough to me, but you won't find that advice in the
current documentation either, AFAICT.

> OTOH, you could equally argue that the new font backend stuff from the
> Unicode merge slows Emacs for people who only ever edits ASCII, and
> that disabling these backends should be an "easily disoverable and
> advertised posibility". But currently the only way to disable a
> specific font backend is via (initial|default)-frame-alist, and no one
> has complained yet.

Sure. If someone complained, it would probably idicate there was an
issue to be solved? As it happens, Drew did complain.

Also, this is not (only) about making `bidi-display-reordering' a custom
variable. It is about releasing Emacs 24 with still-not-widely-tested
bidi support, which quite possibly adds zero value for most users[1],
but does add significant problems at least in some (possibly as yet
unknown) circumstances. It might be a good idea, but I don't see why you
shouldn't be sincere about it and document the implications and
safeguard measures properly. IMO just saying something to the effect of
"bidi support can bring various problems and can be disabled by doing
AB, but we hope you don't disable it and instead help us improve it by
reporting any problems you encounter" might have better effect than
everybody switching off bidi for good after encountering the first
problem and then finding "Emacs 24 bidi slows things down, just turn it
off with AB" on the Internet.   

[1] Just in case: that of course doesn't mean it's not great or
necessary to have it.

-- 
Štěpán