I was messing around with fix and after messing around with it I came across some weird behavior, namely that 0 * undefined is *** Exception: Prelude.undefined and undefined * 0 is 0. Which also means that fix (0 *) is *** Exception: <<loop>> and fix (* 0) is 0.
After playing around with it it seems like the reason is because it is non-trivial to make it short circuit in both directions, as that doesn't really make much sense, without some sort of weird parallel computation and start with the first non-bottom returned.
Is this kind of thing seen in other places (reflexive functions that aren't reflexive for bottom values), and is it something I can safely rely on? Also is there a practical way to make both (0 *) and (* 0) evaluate to zero regardless of the value passed in.