GNU bug report logs - #17130
24.4.50; Deficient Unicode case folding

Previous Next

Full log

View this message in rfc822 format

From: Eli Zaretskii <eliz <at> gnu.org>
To: nbtrap <at> nbtrap.com
Cc: 17130 <at> debbugs.gnu.org
Subject: bug#17130: 24.4.50; Deficient Unicode case folding
Date: Sat, 29 Mar 2014 09:45:10 +0300

> From: nbtrap <at> nbtrap.com
> Cc: 17130 <at> debbugs.gnu.org
> Date: Fri, 28 Mar 2014 15:31:09 -0400
> 
> Eli Zaretskii <eliz <at> gnu.org> writes:
> 
> >> M-: (compare-strings "σ" nil nil "ς" nil nil t)
> >> 
> >> ==> -1  ;; should be t
> >
> > No, because these characters are not a case pair.
> 
> They're not a case pair in Emacs, but they should compare equally under
> Unicode case folding.

Emacs doesn't currently support that.

> >> Can someone that knows a thing about Unicode and emacs case tables speak
> >> to whether the latter could suffice for implementing full Unicode case
> >> folding?
> >
> > What is "full Unicode case folding"?
> 
> Somthing that implements this:
> http://www.unicode.org/Public/UNIDATA/CaseFolding.txt
> 
> And perhaps more.  I don't know, but someone on this list probably does.
> 
> If you look about a third of the way down, there's a line saying that
> U+03C2 (ς) should fold into U+03C3 (σ).

Patches are welcome to import those tables into Emacs, and make case
folding support them.

Previous Next

GNU bug tracking system
Copyright (C) 1999 Darren O. Benham, 1997,2003 nCipher Corporation Ltd, 1994-97 Ian Jackson.