The parameterizable maybe monad, obtained by composing an arbitrary monad with the Maybe monad.
Computations are actions that may produce a value or fail.
The return function yields a successful computation, while >>= sequences two subcomputations, failing on the first error.
Support for computations with failures.
Support for computations with failures. This is a fork of the MaybeT package by Eric Kidd, but compatible with the type-family based monad classes of the monads-tf package.
This package is deprecated: the MaybeT transformer exists in the transformers package nowadays, and the only advantage this package provides over that one is the presence of a MonadFix instance, but it's incorrect anyway.
Support for computations with failures. This package is a fork from the MaybeT package by Eric Kidd, changed to depend on transformers instead of mtl. It also adds a few more utility functions.