RE: diacritic-fold-search?

[Drew Adams]

> Is there a way to search ignoring diacritics, e.g. capturing "apres"
> both with and without an accent grave over the "e"? 

Great question.  I don't think so, but I'm guessing that lots of users could
make good use of such a feature!

Unless someone points out here that this is already possible, why don't you
submit an enhancement request for this feature (`M-x report-emacs-bug' is also
for enhancement requests): be able to toggle Isearch distinguishing certain sets
of similar chars (diacritics).

There could be predefined sets of equivalence classes of chars (e.g., the same
letter, modulo diacritical marks).  And users could be able to customize these
classes.

Likewise, for punctuation chars that are very similar (in purpose/visually),
such as straight quotes and curly quotes, and no-break hyphen, hyphen, and the
various dashes.

Likewise, for whitespace chars other than the standard SPC, TAB, etc.  For
whitespace, I believe there might be some handling of additional chars such as
no-break space, but what's needed, here too, is a simple way to toggle
distinguishing them on/off.

But your use case is the best one: be able to optionally ignore diacritical
marks when searching.