The Monad Transformer Library. Contribute to mtl development by creating an account on GitHub. The MaybeT monad. See jpnfoto.se for more widely-used version. Our Functor instance and our implementation. Clean Alternatives with MaybeT. 18 Nov Haskell's abstraction facilities are awesome. Functor, Applicative, and Monad are all great, and Maybe is a pretty.
Maybet - ist