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.<$> ) :: (TryMerge f, Mergeable a, Mergeable b, Functor f) => (a -> b) -> f a -> f bgrisette Grisette.Unified.Lib.Control.Applicative <$> with MergingStrategy knowledge propagation.
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.<$ ) :: (TryMerge f, Mergeable a, Mergeable b, Functor f) => b -> f a -> f bgrisette Grisette.Unified.Lib.Control.Monad <$ with MergingStrategy knowledge propagation.
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.<$!> ) :: (MonadTryMerge m, Mergeable a, Mergeable b) => (a -> b) -> m a -> m bgrisette Grisette.Unified.Lib.Control.Monad <$!> with MergingStrategy knowledge propagation. Merging is always strict so we can directly use .<$>.
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.$> ) :: (TryMerge f, Mergeable a, Mergeable b, Functor f) => f a -> b -> f bgrisette Grisette.Unified.Lib.Data.Functor $> with MergingStrategy knowledge propagation.
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.<$ ) :: (TryMerge f, Mergeable a, Mergeable b, Functor f) => b -> f a -> f bgrisette Grisette.Unified.Lib.Data.Functor <$ with MergingStrategy knowledge propagation.
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.<$> ) :: (TryMerge f, Mergeable a, Mergeable b, Functor f) => (a -> b) -> f a -> f bgrisette Grisette.Unified.Lib.Data.Functor <$> with MergingStrategy knowledge propagation.
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<<-$ ) :: h a b -> (h a b -> h a' b) -> h a' bhistogram-fill Data.Histogram.Fill Apply function which modify builder
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<$> ) :: Functor f => (a -> b) -> f a -> f bhledger-web Hledger.Web.Import 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 <$> (2,2) (2,True)
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<$> ) :: Functor f => (a <-> b) -> f a -> f binvertible Control.Invertible.Functor An infix synnonym for fmap.
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>$ ) :: Functor f => a -> f a -> f ()invertible Control.Invertible.Monoidal Given a value an an invariant for that value, always provide that value and ignore the produced value. fmap . flip consts ()