Subject: Re: bug#22090: Isearch is sluggish and eventually refuses further service with "[Too many words]".

From: Artur Malabarba <[email-masked]>
Date: Fri, 4 Dec 2015 16:06:40 +0000

2015-12-04 15:23 GMT+00:00 Eli Zaretskii <[email-masked]>:
>> Date: Fri, 4 Dec 2015 15:16:23 +0000
>> From: Artur Malabarba <[email-masked]>
>> Cc: Alan Mackenzie <[email-masked]>, [email-masked]
>>
>> 30f3432 * lisp/character-fold.el: Remove special case-folding support
>>
>> (character-fold-to-regexp): Remove special code for
>> case-folding.  Char-fold search still respects the
>> `case-fold-search' variable (i.e., f matches F).  This only
>> removes the code that was added to ensure that f also matched
>> all chars that F matched.  For instance, after this commit, f
>> no longer matches 𝔽.
>
> Thanks.  Is there any reasonably simple way of describing the
> resulting limitations (i.e. what will NOT match) on the user manual
> level?

Basically, 'a' will match similar characters (like '𝑎' and 'á') and
their upper-case equivalents (like 'Á'). 'a' will NOT match characters
similar to 'A' that don't have a lower-case equivalent (like '𝔸') in
the unicode standard.