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<$> ) :: Functor f => (a -> b) -> f a -> f bopt-env-conf OptEnvConf 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 -> f b -> f aopt-env-conf OptEnvConf.Parser 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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<$> ) :: IsoFunctor f => Iso alpha beta -> f alpha -> f betapartial-isomorphisms Control.Isomorphism.Partial.Prim No documentation available.
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prettyprinter-compat-ansi-wl-pprint Text.PrettyPrint.ANSI.Leijen No documentation available.
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prettyprinter-compat-ansi-wl-pprint Text.PrettyPrint.ANSI.Leijen No documentation available.
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.:$ ) :: SafeJSON a => Object -> Key -> Parser asafe-json Data.SafeJSON Similar to .:, but uses safeFromJSON instead of parseJSON to parse the value in the given field.
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.:$! ) :: SafeJSON a => Object -> Key -> Parser (Maybe a)safe-json Data.SafeJSON Similar to .:!, but uses safeFromJSON instead of parseJSON to maybe parse the value in the given field.
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.:$? ) :: SafeJSON a => Object -> Key -> Parser (Maybe a)safe-json Data.SafeJSON Similar to .:?, but uses safeFromJSON instead of parseJSON to maybe parse the value in the given field.
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.=$ ) :: (SafeJSON a, KeyValue e kv) => Key -> a -> kvsafe-json Data.SafeJSON Similarly to .=, but uses safeToJSON instead of toJSON to convert the value in that key-value pair.
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<<$>> ) :: (a -> IO b) -> Maybe a -> IO (Maybe b)status-notifier-item StatusNotifier.Util No documentation available.