Reference found where even-sized list expected at pm602312.pl line 2
 (W misc) You gave a single reference where Perl was expecting a list
 with an even number of elements (for assignment to a hash). This usually
 means that you used the anon hash constructor when you meant to use
 parens. In any case, a hash requires key/value pairs.
    
        %hash = { one => 1, two => 2, };        # WRONG
        %hash = [ qw/ an anon array / ];        # WRONG
        %hash = ( one => 1, two => 2, );        # right
        %hash = qw( one 1 two 2 );                      # also fine