Isearch has a couple of toggles like case-fold, isearch-invisible and now
char-fold.

After updating, I noticed that the prompt for the regular `C-s` is now
"Char-fold Isearch: ".

Should that "Char-fold" prefix be there? If so, we should also display what
other isearch options are in effect (case-fold, etc).

Suggestion:
- The prefix be kept the same as before ("Isearch: ") for brevity.
- The moment a user starts Isearch (or when user calls a command during
Isearch using some binding), the effective isearch properties are flashed
in the echo area. That "flashing" would look just as the case-sensitivity
state is flashed on hitting `M-c` during isearch. An example of such
flashed message could be

    [Case-fold: on Char-fold: on  Search-invisible: off]

- If we don't want to flash that message, the message can be displayed and
be allowed to stay there till user starts/resumes typing in the minibuffer.

Thoughts?

On Wed, Jun 24, 2015 at 9:56 PM Artur Malabarba <bruce.connor.am@gmail.com>
wrote:

> > So the most important remaining problem is how to combine char-folding
> > with ‘isearch-lax-whitespace’ and ‘search-whitespace-regexp’.
> > It seems this will require duplicating some code between these two.
>
> I took a shot at this on the last commit. `character-fold-to-regexp'
> now takes a second argument (lax), when this is non-nil it appends a +
> to the regexp generated from whitespace characters.
> It doesn't take `search-whitespace-regexp' into consideration, but I
> don't know if that would even make sense given that a character-folded
> space is even more general (matches more characters) than what's
> specified by `search-whitespace-regexp'.
>
>