c:\@Work\Perl\monks>perl -wMstrict -le
"use Regexp::Common qw[ delimited ];
 my $P1 = '../matrix-ops/matopmul.mk';
 my $P2 = 'C:\matrix-ops\matopmul.mk';
 print \"P1 has path\n\" if ($P1 =~ /$RE{delimited}{-delim => '\/'}/ );
 print \"P2 has path\n\" if ($P2 =~ /$RE{delimited}{-delim => '\/'}/ );
"
P1 has path

c:\@Work\Perl\monks>perl -wMstrict -le
"use Regexp::Common qw[ delimited ];
 my $P1 = '../matrix-ops/matopmul.mk';
 my $P2 = 'C:\matrix-ops\matopmul.mk';
 print \"P1 has path\n\" if ($P1 =~ m{$RE{delimited}{-delim => '\/'}} );
 print \"P2 has path\n\" if ($P2 =~ m{$RE{delimited}{-delim => '\/'}} );
"
P1 has path

P2 has path