Secondly you're misrepresenting the defined behaviour of comma in scalar context. It isn't that comma acts that way, it is that lists act that way and comma normally delimits lists

I'm inclined to respectfully disagree here. According to perlop, "Binary "," is the comma operator. In scalar context it evaluates its left argument, throws that value away, then evaluates its right argument and returns that value. This is just like C's comma operator. " I feel like this is a better way to think about it, since it's consistent with the doctrine of "there's no such thing as a list in scalar context."