Re: Questions about isearch

[Mike Kupfer <m.kupfer@acm.org>]

Eli Zaretskii wrote:

> > From: Mike Kupfer <m.kupfer@acm.org>
> > cc: emacs-devel <emacs-devel@gnu.org>
> > Date: Wed, 25 Nov 2015 15:04:37 -0800
> > 
> > To give a more concrete example, if I try to replace "papa" ("pope" in
> > Italian) with "Francis", I would not want Emacs to also replace (or even
> > suggest replacing) "papà" ("dad" in Italian) with "Francis".
> 
> By default, Emacs won't.  But if you set replace-character-fold
> non-nil, it will.

Ah, I see; thanks.

Assuming that there won't be any major changes for 25.1 in this area, I
think it would be helpful for the "Lax Search" Info node to say
something about replace-character-fold, particularly since that node
mentions the relationship between case-fold-search and replace commands.
And maybe replace-character-fold should be listed in the "Search
Customizations" node?

Also, I'm confused about the exact semantics of replace-character-fold.
Its help string says it applies to query-replace.  Experimentation shows
that it also applies to replace-string, but not replace-regexp ("[ab]"
does not match "ä" even when replace-character-fold is non-nil).  I'm
not sure what's intended here, particularly since replace-regexp does
honor case-fold-search.

And speaking of case-fold-search, it is documented as buffer-local when
set.  Should search-default-regexp-mode and replace-character-fold do
the same?

regards,
mike