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1. class Arrow a => ArrowChoice (a :: Type -> Type -> Type)

   base	Control.Arrow

   Choice, for arrows that support it. This class underlies the if and case constructs in arrow notation. Instances should satisfy the following laws:

   • left (arr f) = arr (left
     f)

   • left (f >>> g) = left f >>>
     left g

   • f >>> arr Left = arr
     Left >>> left f

   • left f >>> arr (id +++ g) =
     arr (id +++ g) >>> left f

   • left (left f) >>> arr assocsum
     = arr assocsum >>> left f

   where

   assocsum (Left (Left x)) = Left x
   assocsum (Left (Right y)) = Right (Left y)
   assocsum (Right z) = Right (Right z)
   

   The other combinators have sensible default definitions, which may be overridden for efficiency.

2. class Arrow a => ArrowLoop (a :: Type -> Type -> Type)

   base	Control.Arrow

   The loop operator expresses computations in which an output value is fed back as input, although the computation occurs only once. It underlies the rec value recursion construct in arrow notation. loop should satisfy the following laws:

   • extension loop (arr f) = arr (\ b -> fst (fix (\ (c,d) -> f (b,d))))
   • left tightening loop (first h >>> f) = h >>> loop f
   • right tightening loop (f >>> first h) = loop f >>> h
   • sliding loop (f >>> arr (id *** k)) = loop (arr (id *** k) >>> f)
   • vanishing loop (loop f) = loop (arr unassoc >>> f >>> arr assoc)
   • superposing second (loop f) = loop (arr assoc >>> second f >>> arr unassoc)
   where

   assoc ((a,b),c) = (a,(b,c))
   unassoc (a,(b,c)) = ((a,b),c)
   

3. newtype ArrowMonad (a :: Type -> Type -> Type) b

   base	Control.Arrow

   The ArrowApply class is equivalent to Monad: any monad gives rise to a Kleisli arrow, and any instance of ArrowApply defines a monad.

4. ArrowMonad :: a () b -> ArrowMonad (a :: Type -> Type -> Type) b

   base	Control.Arrow

   No documentation available.

5. class ArrowZero a => ArrowPlus (a :: Type -> Type -> Type)

   base	Control.Arrow

   A monoid on arrows.

6. class Arrow a => ArrowZero (a :: Type -> Type -> Type)

   base	Control.Arrow

   No documentation available.

7. ArrowT :: Type

   template-haskell	Language.Haskell.TH

   ->
   

8. Arrows :: Extension

   template-haskell	Language.Haskell.TH

   No documentation available.

9. Arrows :: Extension

   template-haskell	Language.Haskell.TH.LanguageExtensions

   No documentation available.

10. ArrowT :: Type

    template-haskell	Language.Haskell.TH.Syntax

    ->
    

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