http://www.perlmonks.org?node_id=11105319


in reply to Thoughts on "one function, flexible arguments"?

I do not agree with Postel: "be conservative" in what you accept, too. Otherwise you have just made a too-generalized promise to anyone who shows up that, somehow, you will do the right thing with anything they offer. My point being that I could never "desk check" YOUR code, unless I could somehow comb the universe to discover each and every call. The "correct" operation of this code as written depends on the "correctness" of every possible caller – and could offer no assistance at all in detecting that a bug existed in any of them. Of course, "realizing that a bug exists" is always the first hurdle, and "determining where it is" is the second. Maybe i would rewrite Postel's rule as: "be suspicious as hell, because if you don't catch the CALLER'S bug, no one will."