About your line: 
    my $parm = $_[0] || $_;
What is you call this? 
test(0);
test("");
You should wait for Perl 6 and use the new operator //.

In reply to Re x 2: Can I tell a sub to take $_ instead of @_ (like some builtins do) by Sweeper
in thread Can I tell a sub to take $_ instead of @_ (like some builtins do) by statebelt

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