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Within LTS Haskell 24.4 (ghc-9.10.2)
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<$ ) :: Functor f => a -> f b -> f adistribution-opensuse OpenSuse.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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<$ ) :: Functor f => a -> f b -> f adistribution-opensuse OpenSuse.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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<$!> ) :: Monad m => (a -> b) -> m a -> m bdistribution-opensuse OpenSuse.Prelude Strict version of <$>.
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<$> ) :: Functor f => (a -> b) -> f a -> f bdistribution-opensuse OpenSuse.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 <$> (2,2) (2,True)
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extrapolate Test.Extrapolate function application between expressions
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<$> ) :: Functor f => (a -> b) -> f a -> f bfaktory Faktory.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 <$> (2,2) (2,True)
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.$ ) :: forall x (xs :: [Type]) . Show x => Predicate (x ': xs) -> (Var, x) -> Predicate xsfalsify Test.Falsify.Predicate Infix version of at Typical usage example:
assert $ P.relatedBy ("equiv", equiv) .$ ("x", x) .$ ("y", y)
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<$$$> ) :: (Functor f, Functor g, Functor h) => (a -> b) -> f (g (h a)) -> f (g (h b))fuzzyset Data.FuzzySet.Utils No documentation available.
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<$$> ) :: (Functor f, Functor g) => (a -> b) -> f (g a) -> f (g b)fuzzyset Data.FuzzySet.Utils No documentation available.
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<$.> ) :: Functor f => Walk c b d -> f (GTraversal c a b) -> f (GTraversal c a d)greskell Data.Greskell