http://www.perlmonks.org?node_id=930513


in reply to Re^9: Short-circuiting a map list. (This works! But ...)
in thread Short-circuiting a map list.

You can argue all you want, but it's not going to change the fact that the return value of loops (including the bare loop) is not defined. They can and do produce junk in some circumstances. There was talk of making loops act like map wrt to their return value, but it hasn't been done.