14 May
2002
14 May
'02
3:32 p.m.
Dylan Thurston wrote: [snip]
I've often been bothered by the inconsistent treatment of laws in the report; why are there laws for functors, monads, and quot/rem and div/mod, and not much else? I'm pleased to see that the laws that are given actually do have exceptions. [snip] Even the quot/rem and div/mod laws are not always true, for example if you divide by zero, or (for div/mod, where overflows cause an error) where you get an overflow with (x `div` y) * y. Perhaps we need something in the report to state that these laws like these and the Monad laws are only intended as aspirations rather than promises.