Re: On language-dependent defaults for character-folding

[Eli Zaretskii]

> From: John Wiegley <address@hidden>
> Cc: address@hidden,  address@hidden,  address@hidden,  address@hidden,  
> address@hidden
> Date: Fri, 26 Feb 2016 16:48:21 -0800
> 
> 
> [1:text/plain Hide]
> 
> >>>>> Eli Zaretskii <address@hidden> writes:
> 
> > The discussion (with a few exceptions) is about how to augment the current
> > implementation to make it more acceptable to various needs and cultures. So
> > I think it's directly related to the pretest, and so moving it to
> > emacs-tangents would be wrong.
> 
> In that case, can you please propose a plan for reaching such acceptability?
> If I can clearly see what we're aiming toward, it will give me a context for
> reading these messages, and help focus the discussion.
> 
> For example: makes exactly it not acceptable today? what are the desirable
> features of an "ideal implementation"? what are the variables we're trying to
> hammer down? etc. Then I think we can meaningfully tackle this issue by
> breaking it into the smaller pieces that make it up.

The simplest change would be to have character-folding disabled by
default in some European locales whose users expressed objections to
having it on by default, due to folding of some characters that
shouldn't be folded in the languages of those locales.

Another, more complex, but still simple enough, possibility would be
to have character-folding on by default, but have the problematic
foldings filtered out from the regexp used by it.  We could either
always filter out all of them, or filter out only some of them, as
determined by the user locale.  For example, in the Spanish locales, ñ
will not be folded.

The next alternative is to come up with a fine-grained classification
of character-folding, and provide user options to control each one of
them independently, with the defaults determined by the user locale.
For example, one class of folding is the one required for matching
pre-composed characters such as á with its decomposed variant á;
another class is for finding "similar" characters, such as finding ⒜
when looking for a.  There should probably be classes that are
disliked by users of certain languages, such as ñ for Spanish.
Etc. etc.  (I think this alternative needs more research and user
feedback, and so is probably not for the release branch.)

Maybe there are more alternatives, I don't know.  It's not like they
were explicitly proposed by someone; the above is just my personal
conclusions from reading the discussion.