bug#21140: 25.0.50; Isearch "char-fold" by default

[Sebastien Vauban <sva-news-D0wtAvR13HarG/iDocfnWg@public.gmane.org>]

Artur Malabarba <bruce.connor.am-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> writes:
>> First, the default behavior seems changed, and I'm not really aware
>> (yet) of what exactly "char folding" is.  I did not found any
>> definition for this, even if I have some ideas.
>
> There's another thread here about hiding that string from the
> prompt. I agree it's a little confusing, and char folding can be used
> without flashing it on the user. Somebody offered to do something
> about it, though I forget who.

I wasn't specifically asking to remove it from the prompt. If "char-fold
isearch" is a different beast from the "default Emacs 24 isearch", then
it should be visible somehow.

And I've no current opinion on whether or not that should be displayed
in the prompt (or somewhere else).

>> Second, I don't think the new default is right.  I prefer to search
>> for text, not for regexps by default.  Otherwise, we could also
>> invert `C-s' and `C-M-s', right?
>
> Char fold search is a text search, not a regexp search. It does use
> a regexp underneath, but that should be invisible to the user. You
> type some text and it matches that text or similar texts.

"Char fold" search is a "fuzzy" search, then, similar to
https://github.com/auto-complete/fuzzy-el?

What comes the name "char fold" from?  It's not very intuitive to me
that it's some sort of fuzzy search; moreover, it looks like "case fold"
search, which is again something different...

>> Finally, it *seems* buggy to me when using `C-w' to complete the
>> search pattern (or shouldn't we use that anymore?).
>
> I can't see your link on my phone, but if it's like you describe then
> it's certainly a bug.  I'll try out your examples when I get home.

Thanks!

Best regards,
  Seb