my @doubled = map { $_, $_ } ( 1,3,4,5,6,6 ); my @flattened = map { @$_ } ( [ 1,2,3], [ "A","B","C" ], [ $var1, $var2, $var3 ] ); my %squares_hash = map { $_ => $_ * $_ } ( 1,2,3,4,5,6 );