semigroupoids-3.1: Haskell 98 semigroupoids: Category sans id

Portabilityportable
Stabilityprovisional
MaintainerEdward Kmett <ekmett@gmail.com>
Safe HaskellSafe

Data.Functor.Plus

Description

 

Synopsis

Documentation

class Alt f => Plus f whereSource

Laws: 

 zero <!> m = m
 m <!> zero = m

If extended to an Alternative then zero should equal empty.

Methods

zero :: f aSource

Instances

Plus [] 
Plus IO 
Plus Maybe 
Plus Seq 
Plus IntMap 
Plus Option 
MonadPlus m => Plus (WrappedMonad m) 
Ord k => Plus (Map k) 
(Bind f, Monad f) => Plus (MaybeT f) 
(Apply f, Applicative f) => Plus (ListT f) 
Plus f => Plus (IdentityT f) 
Alternative f => Plus (WrappedApplicative f) 
ArrowPlus a => Plus (WrappedArrow a b) 
Plus f => Plus (WriterT w f) 
Plus f => Plus (WriterT w f) 
Plus f => Plus (StateT e f) 
Plus f => Plus (StateT e f) 
Plus f => Plus (ReaderT e f) 
(Bind f, Monad f, Error e) => Plus (ErrorT e f) 
Plus f => Plus (Static f a) 
Plus f => Plus (RWST r w s f) 
Plus f => Plus (RWST r w s f) 

module Data.Functor.Alt