Johannes Waldmann wrote: >> I think the crux of >> the matter was that a monad is too general. Either there is a result or >> there is not. That's precisely the intended use of a Maybe. > > Indeed "Monad m =>" is dangerous here > because not every Monad has a reasonable definition of "fail". > > But that seems to be a problem in the (current) definition of "Monad", > and its solution was "MonadZero", no?
I agree that the MonadZero class with a useful 'zero' :: m a would be the right abstraction for views. But MonadZero is not part of base, mtl or any other common package, or am I missing something? Changing this is beyond a simple heap package ;) -- Früher hieß es ja: Ich denke, also bin ich. Heute weiß man: Es geht auch so. - Dieter Nuhr _______________________________________________ Haskell-Cafe mailing list [email protected] http://www.haskell.org/mailman/listinfo/haskell-cafe
