bug#3687: 23.1.50; inconsistency in multibyte eight-bit regexps

[YAMAMOTO Mitsuharu]

>>>>> On Sat, 27 Jun 2009 12:36:03 +0300, Eli Zaretskii <eliz@gnu.org> said:

>> Date: Sat, 27 Jun 2009 10:30:10 +0900
>> From: YAMAMOTO Mitsuharu <mituharu@math.s.chiba-u.ac.jp>
>> Cc: 3687@emacsbugs.donarmstrong.com
>> 
>> >>>>> On Fri, 26 Jun 2009 16:43:25 +0300, Eli Zaretskii <eliz@gnu.org> said:
>> 
>> >> Date: Fri, 26 Jun 2009 18:56:50 +0900 (JST)
>> >> From: YAMAMOTO Mitsuharu <mituharu@math.s.chiba-u.ac.jp>
>> >> Cc: 
>> >> 
>> >> The following results look inconsistent:
>> >> 
>> >> (string-match (string-to-multibyte "\x80") (string-to-multibyte "\x80"))
>> >> => 0
>> >> (string-match (string-to-multibyte "\x80") "\x80")
>> >> => nil
>> >> 
>> >> (string-match (string-to-multibyte "[\x80]") (string-to-multibyte "\x80"))
>> >> => nil
>> >> (string-match (string-to-multibyte "[\x80]") "\x80")
>> >> => 0
>> 
>> > Please tell why you think they are inconsistent.
>> 
>> I thought there's no room for argument about their inconsistency with
>> respect to the specification of "[...]" in regexps.

> Well, obviously there is such a room.  Please consider explaining why
> you think there's inconsistency.

It seemed to be too obvious to explain and I hesitated to do that.
Anyway, I assume "C" and "[C]" work equivalently as regexps if the
character C has no special meaning in either context.

                                    YAMAMOTO Mitsuharu
                                mituharu@math.s.chiba-u.ac.jp