G'day all. Quoting Josef Svenningsson <[EMAIL PROTECTED]>:
> I think it's unfair to the monad transformers to simply say that they > don't obey the law. The interesting thing is whether they *preserve* > the law. A monad transformer T preserves a law if given a monad M > which obeys the law holds then the monad T M obeys the law. The law in question is that mzero is a right-zero for bind. How can an underlying monad be said to "obey" this law if it doesn't support mzero? Cheers, Andrew Bromage _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
