Re: regex and case-fold-search problem

[Kenichi Handa <handa@etl.go.jp>]

In article <9003-Fri23Aug2002185625+0300-eliz@is.elta.co.il>, "Eli Zaretskii" <eliz@is.elta.co.il> writes:
>>  (let ((case-fold-search nil))
>>    (string-match "[A-_]" "A")) => 0
>>  (let ((case-fold-search t))
>>    (string-match "[A-_]" "A")) => nil
>>  (let ((case-fold-search t))
>>    (string-match "[A_]" "A")) => 0

> Does that happen because under case-fold-search non-nil the
> characters on the range specification are downcased?

Yes.

>>  In my opinion, specifying ranges by chars are nonsense
>>  because there should be no semantics in the order of
>>  characters codes.

> Sorry, I don't understand: how would one specify a range _except_
> with two characters and a dash between them?  What am I missing?

I mean that the concept of character range itself is not
good.  A character code is just an identifier of a
character.  We usually don't think about "a range of
identifiers" (e.g. "symbols in the range between t and nil"
is nonsense).

---
Ken'ichi HANDA
handa@etl.go.jp