ups! Yes, system returns 0 on success, so with the explict system('foo') ==0 || die "bar"; in this situation, that's just what's wanted. If the LHS of the || evaluates as true, Perl won't bother with the RHS.

The use of &&/and you point to is equivalent to an if : If the LHS of an && is true, Perl goes on to evaluate the RHS, but doesn't bother if the LHS is false. So his code is correct on that aspect.

I don't know enough Perl history to answer the original question, though =(

Just for the record, the 'english' and and or are 'super-low precedence' versions of && and ||

Philosophy can be made out of anything. Or less -- Jerry A. Fodor