RE: char equivalence classes in search - why not symmetric?

[Drew Adams]

> > ie, the default it to catch *exactly* what the user types.
> 
> I disagree.  But if you want to add a Custom var to let users change the
> default, that's fine by me.
> Personally for those rare cases when I need to explicitly disable
> case-folding in isearch, `M-c' works well enough,

There already is such a Custom var: `case-fold-search'.

And in the rare cases where I need to explicitly _enable_ case
folding in Isearch, `M-c' works well enough.  I've customized
`case-fold-search' to turn it OFF by default.

But the question Jean-Christophe raised is about the _default_
behavior.

And BTW, he raised it specifically wrt char folding, not case folding.

The attempt, each time, to hark back to the fact that Emacs defaults
_case_ folding to ON, in the context of a discussion about _char_
folding, is lamentable.

We can deal with case folding later, if there is enough interest in
reconsidering its default behavior.  In this thread the question is
about char folding, first and foremost.