$ref = @_;

Sorry, but that's not correct, it suffers from the same problem as the OP: it puts the array @_ into scalar context, meaning that $ref will hold the number of elements in @_, instead of its first element as intended. You'd need to write my ($ref) = @_;, as the parentheses on the left side place the right side into list context, and this will cause $ref to be assigned the first element of the array (and the rest of the elements to be ignored in this case).

Also, this code won't work under strict (also note $reference_of_example vs. $ref_example). When posting code examples, please make sure to test them under strict and warnings.