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Within LTS Haskell 24.28 (ghc-9.10.3)

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

    base 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)

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

    base Control.Applicative

    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 -> b) -> f a -> f b

    base Data.Functor

    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)

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

    hedgehog Hedgehog.Internal.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. (<$>) :: Functor f => (a -> b) -> f a -> f b

    semigroupoids Data.Functor.Apply

    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)

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

    semigroupoids Data.Functor.Bind

    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)

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

    comonad Control.Comonad

    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)

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

    ghc GHC.HsToCore.Monad

    No documentation available.

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

    ghc GHC.Prelude.Basic

    No documentation available.

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

    ghc GHC.Utils.Monad

    No documentation available.

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