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Within LTS Haskell 24.6 (ghc-9.10.2)

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  1. ($!) :: (a -> b) -> a -> b

    xmonad-contrib XMonad.Config.Prime

    Strict (call-by-value) application operator. It takes a function and an argument, evaluates the argument to weak head normal form (WHNF), then calls the function with that value.

  2. ($?) :: (Eq a, Functor m) => m [a] -> [a] -> m Bool

    xmonad-contrib XMonad.Hooks.ManageHelpers

    q $? x. if the result of x isSuffixOf q, return True

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

    xmonad-contrib XMonad.Prelude

    Flipped version of <$.

    Examples

    Replace the contents of a Maybe Int with a constant String: 
    >>> Nothing $> "foo"
Nothing

    >>> Just 90210 $> "foo"
Just "foo"
    Replace the contents of an Either Int Int with a constant String, resulting in an Either Int String: 
    >>> Left 8675309 $> "foo"
Left 8675309

    >>> Right 8675309 $> "foo"
Right "foo"
    Replace each element of a list with a constant String: 
    >>> [1,2,3] $> "foo"
["foo","foo","foo"]
    Replace the second element of a pair with a constant String: 
    >>> (1,2) $> "foo"
(1,"foo")

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

    base 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

  5. (<$>) :: 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)

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

    base Control.Monad

    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

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

    base Control.Monad

    Strict version of <$>.

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

    base Control.Applicative

    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

  9. (<$>) :: 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)

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

    base Control.Monad.Instances

    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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