Dear Monks

I tried to extract a list of modules installed on my system by the following code
sub _find_modules {
    my $dir = shift ;
    my ($inst) = ExtUtils::Installed->new();
    my $packlist = $inst->packlist("My_Package");
    return grep { s/(.*?\Q$dir\E)(\w+)(\.pm)$/$2/ } %$packlist ;
}

[download]
So $dir contains a path specifying a specific sub_package.
Anyway, there seems tobe a problem with the $2, because running this code gives me the following warnings
Use of uninitialized value in pattern match (m//) at /usr/lib/perl5/si
+te_perl/5.8.7/My_Package.pm line 309.
Use of uninitialized value in pattern match (m//) at /usr/lib/perl5/si
+te_perl/5.8.7/My_Package.pm line 309.

[download]
I get the feeling that this happens when $2 is not defined
Any suggestions whats wrong with this code and how to solve it?

Thanks a lot
LuCa

In reply to warnings and grep problem by jeanluca

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