Re: UTF-8 and matching [^\s]

Stuart Hughes <[email protected]> writes:
>Hi everyone,
>
>I've run into problems matching the regex [^\s] on RedHat 8/9 and the
>version of perl shipped with it (5.8.0).  

It isn't 5.8.0 is 5.8.0-with-RedHatBugs :-(
To be fair to them it is some development track thing - there was 
an experimental scheme to honour the locale UTF-8-ness.

But experiment failed and no "released" perl ever had the mis-feature.

>
>The problem:
>------------
>Given the string: $_ = "%define pfx x";
>The regex: m,^%define\s+([^\s]+),;
>
>Does not match on RH8/9 unless you change the LANG environment varible
>to a non-UTF-8 entry.
>
>For some reason, the pragma: no utf8; doesn't seem to make any difference.
>
>I can get it to work by changing the pattern to: m,^%define\s+([\S]+),;
>but this is not what I want because I have legacy scripts that I can't
>easily change. Furthermore, I want to use patterns like: [^\s/] (e.g
>more than one negated character type).

It breaks Tk's Makefile.PL too.

>
>I found a work around.  If I change the start-up line to include LANG=C,
>it works:
>
>eval 'LANG=C exec perl -w -S $0 ${1+"$@"}'
>       if $running_under_some_shell;
>
>I've attached a test script that shows the problem (remove the LANG=C to
>make it break).

Unless one is in a non-UTF8 locale already when if course it works.

>
>Question:
>---------
>Does anyone know a better way of working around this problem? (e.g.
>getting 'no utf8;' to work.

You can only do that by changing the binary (e.g. to REAL 5.8.0 
or any later 5.8.*) and you said you didn't want to do that.