Hi Dave Mielke <[email protected]> writes:
> [quoted lines by Aura Kelloniemi on 2018/10/09 at 11:22 +0300] > >But it probably does not help if the pattern contains a dot to match a > >single > >character, which happens to be a non-ASCII character in the input. E.g. a > >pattern ".> " will not match "λ> ". Am Iright? > Yes, but, if we do some clever parsing, we could translate each dot to > something like: > (?:[\x00-\x7f]|[\xc0-\xff][\x80-\xbf]*) This might work. Though it might become a nightmare for the user if their regular expression is malformed and they get back an error message which really does not make any sense to them. I don't know if POSIXregex library has any error reporting capabilities though. > I'm wondering, though, if we should just maybe insist on the use of pcre2 > because it supports wchar_t which brltty uses. Then we wouldn't have to do > any > parsing, character reencoding, etc, and it should just work. Brltty even > already converts the UTF-8 characters in data files to wchar_t for > processing. My personal opinion would be yes. > What I don't know is how pcre2 pattern syntax differs from that of POSIX > extended regular expressions. In case you remind me that it's similar to > Perl, > I'll answer that I've never liked Perl so haven't learned much of it. :-) I never liked Perl either. The only thing that I like about Perl though is its regular expression syntax. Its escaping rules are more consistent than POSIX's, it has many very convenient additional matchers, like \d for [[:digit:]] and \s for [[:space:]]. It supports unicode properties - for example \w can be configured to take into account all Unicode letters. I personally like comments a lot in PCRE (?# Because they make long regexes comprehensible again). PCRE's article on Wikipedia is very comprehensive and a good read for the topic: https://en.wikipedia.org/wiki/Perl_Compatible_Regular_Expressions -- Aura _______________________________________________ This message was sent via the BRLTTY mailing list. To post a message, send an e-mail to: [email protected] For general information, go to: http://brltty.app/mailman/listinfo/brltty
