4.1
- Added instances for
MonadBase, MonadBaseControl, and MonadTransControl.
4.0
3.4.2
- Added 'Data.Either.Combinators'.
3.4.1
- Trustworthy despite UndecidableInstances
3.4
- Delegate
fail to the underlying Monad, rather than error.
3.3
- Inverted roles between
Semigroup and Alt. This let us write Alternative and MonadPlus instances that are compatible.
- Removed the
Functor constraint on most instances in exchange for incurring a Monad constraint on Traversable. EitherT
is after all, a Monad transformer first and foremost.
3.2
- Changed the
Semigroup to use a Semigroup to combine Left branches. Left Alt untouched, so you can mix and match.
3.1
- Added instances for
mtl classes and MonadRandom.
- The meaning of
mapEitherT has changed to match mapErrorT in the mtl. The old mapEitherT is now bimapEitherT.
3.0.3