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1. (<$!>) :: Monad m => (a -> b) -> m a -> m b

   rio	RIO.Prelude

   Strict version of <$>.

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

   rio	RIO.Prelude

   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)
   

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

   diagrams-lib	Diagrams.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
   

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

   diagrams-lib	Diagrams.Prelude

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

   diagrams-lib	Diagrams.Prelude

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

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

   Cabal-syntax	Distribution.Compat.Prelude

   No documentation available.

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

   Cabal-syntax	Distribution.Compat.Prelude

   No documentation available.

8. (=$) :: Eq b => a -> (a -> b) -> a -> Bool

   leancheck	Test.LeanCheck.Utils.Operators

   Equal under, a ternary operator with the same fixity as ==.

   x =$ f $= y  =  f x == f y
   

   > [1,2,3,4,5] =$ take 2 $= [1,2,4,8,16]
   True
   

   > [1,2,3,4,5] =$ take 3 $= [1,2,4,8,16]
   False
   

   > [1,2,3] =$ sort $= [3,2,1]
   True
   

   > 42 =$ (`mod` 10) $= 16842
   True
   

   > 42 =$ (`mod`  9) $= 16842
   False
   

   > 'a' =$ isLetter $= 'b'
   True
   

   > 'a' =$ isLetter $= '1'
   False
   

9. data (a1 :: a ~> b) @@@#@$$ (b1 :: TyFun a b)

   singletons	Data.Singletons

   No documentation available.

10. type (f :: a ~> b) @@@#@$$$ (x :: a) = f @@ x

    singletons	Data.Singletons

    No documentation available.

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