Made sure that num_cmp, fun_cmp and str_cmp return an
answer evaluator when used in scalar context. In other words
$ans_eval = num_cmp(234);
will now work as expected -- you will get one answer evaluator which
checks whether the answer is 234.
Previously you had to write:
($ans_eval) = num_cmp(234);
or else you would have the numeral 1 placed in $ans_eval since
that is how many answer evaluators were created.