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1. (>$<) :: Contravariant f => (a -> b) -> f b -> f a

   base-prelude	BasePrelude.Operators

   This is an infix alias for contramap.

2. (</$>) :: Functor f => (DirTree a -> DirTree b) -> f (AnchoredDirTree a) -> f (AnchoredDirTree b)

   directory-tree	System.Directory.Tree

   Allows for a function on a bare DirTree to be applied to an AnchoredDirTree within a Functor. Very similar to and useful in combination with <$>:

3. (<$) :: Functor f => a -> f b -> f a

   mixed-types-num	Numeric.MixedTypes.PreludeHiding

   Replace all locations in the input with the same value. The default definition is fmap . const, but this may be overridden with a more efficient version.

   Examples

   Perform a computation with Maybe and replace the result with a constant value if it is Just:

   >>> 'a' <$ Just 2
   Just 'a'
   
   >>> 'a' <$ Nothing
   Nothing
   

4. (<$>) :: Functor f => (a -> b) -> f a -> f b

   mixed-types-num	Numeric.MixedTypes.PreludeHiding

   An infix synonym for fmap. The name of this operator is an allusion to $. Note the similarities between their types:

   ($)  ::              (a -> b) ->   a ->   b
   (<$>) :: Functor f => (a -> b) -> f a -> f b
   

   Whereas $ is function application, <$> is function application lifted over a Functor.

   Examples

   Convert from a Maybe Int to a Maybe String using show:

   >>> show <$> Nothing
   Nothing
   

   >>> show <$> Just 3
   Just "3"
   

   Convert from an Either Int Int to an Either Int String using show:

   >>> show <$> Left 17
   Left 17
   

   >>> show <$> Right 17
   Right "17"
   

   Double each element of a list:

   >>> (*2) <$> [1,2,3]
   [2,4,6]
   

   Apply even to the second element of a pair:

   >>> even <$> (2,2)
   (2,True)
   

5. (<$>) :: Functor g => (forall (a :: k) . () => p a -> q a) -> g p -> g q

   rank2classes	Rank2

   No documentation available.

6. (&!$*) :: forall (tag :: Symbol) m t . (Sayable tag m, Foldable t) => (Doc SayableAnn -> Doc SayableAnn) -> t m -> Saying tag

   sayable	Text.Sayable

   A helper operator that applies the first argument (a Prettyprinter adaptation function) to the result of a Foldable collection of Sayable items. This is essentially a combination of the &! and &* operators where the first operation is applied to the entire list, rather than each element of the list (as with &!*).

   >>> sez @"info" $ t'"three:" &- PP.align &!$* [1, 2, 3::Int]
   "three: 1, 2, 3"
   

   As with the &!* operator (and unlike the &* operator), a null collection is passed to the converter first argument. @since: 1.1.0.0

7. (=$&) :: forall c1 c2 c3 i x (m :: Type -> Type) o r . CCatable c1 c2 c3 => c1 i x m () -> c2 x o m r -> c3 i o m r

   stm-conduit	Data.Conduit.Async

   An alias for =$=& by analogy with =$= and =$.

8. (=$=&) :: forall c1 c2 c3 i x (m :: Type -> Type) o r . CCatable c1 c2 c3 => c1 i x m () -> c2 x o m r -> c3 i o m r

   stm-conduit	Data.Conduit.Async

   An operator form of buffer'. In general you should be able to replace any use of =$= with =$=& and $$ either with $$& or =$= and runCConduit and suddenly reap the benefit of concurrency, if your conduits were spending time waiting on each other.

   >>> runCConduit $ CL.sourceList [1,2,3] =$=& CL.consume
   [1,2,3]
   

9. (:$$:) :: ErrorMessage -> ErrorMessage -> ErrorMessage

   type-errors	Type.Errors

   Stack two pieces of error message on top of each other.

10. (<$) :: Functor f => a -> f b -> f a

    LambdaHack	Game.LambdaHack.Core.Prelude

    Replace all locations in the input with the same value. The default definition is fmap . const, but this may be overridden with a more efficient version.

    Examples

    Perform a computation with Maybe and replace the result with a constant value if it is Just:

    >>> 'a' <$ Just 2
    Just 'a'
    
    >>> 'a' <$ Nothing
    Nothing
    

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