because there's more than several ways to do it.. 
my @l3 = map { my $f = $_; ((grep { $f eq $_ } @l2),'null')[0] } @l1;

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In reply to Re: My 'perldar' tells me there is a 'better' solution for this list operation by mreece
in thread My 'perldar' tells me there is a 'better' solution for this list operation by OfficeLinebacker

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