note choroba Two days ago, I was having the same issues. My testing script is a bit more elaborate, but confirms your problem: <c>\w</c> does not work under <c>use locale</c>, whatever the locale is. If you need locale, use posix classes or unicode character properties (provided your locale is unicode based). <br> Discussion on the details can be found in [doc://perlunicode] and [doc://perllocale], but the relevant paragraphs are quite different in each version of Perl. <c> #!/usr/bin/perl use warnings; use strict; my @p_locale = qw/C cs_CZ.UTF8 en_US.UTF8/; my @locale = ('no locale', 'use locale'); my @posix = (q(), 'use POSIX qw/locale_h/; setlocale LC_ALL,"C"', 'use POSIX qw/locale_h/; setlocale LC_ALL,"cs_CZ.UTF8"', ); for my $p_locale (@p_locale) { for my $locale (@locale) { for my $posix (@posix) { print "$p_locale $locale $posix\n"; open my $OUT, '>', 'l.perl' or die "$!"; print {$OUT} << " OUT"; $locale; $posix; my \@chars = qw/283 269 345 225 32 98 99 48 49 50 51 52 32 353 253 382 237/; my \$string = join q[], map chr, \@chars; binmode STDOUT, ':utf8'; my \@regex = (qr/(\\w+)/, qr/([[:alnum:]]+)/, qr/(\\p{Word}+)/); for my \$regex (\@regex) { print "\t\$1" while \$string =~ /\$regex/g; print "\n"; } print sort qw/ci ch/; print "\n"; OUT close $OUT; $ENV{LC_ALL} = $p_locale; system 'perl', 'l.perl'; } } } unlink 'l.perl'; </c> 935400 935400