Scary. I'm starting to do this by default for temporary ugly hacks in my code. :) j @ok_combos = qw( AA57687 UA35124 1PSFODT 1ASFODTN WBSFODTN AA4811 UA25416 1P1049 1AWAS512 WBWASSHO ); my %ok_combos = map { $_ => 1 } @ok_combos;