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.:! ) :: FromJSON a => Object -> Key -> Parser (Maybe a)aeson Data.Aeson.Types Retrieve the value associated with the given key of an Object. The result is Nothing if the key is not present or empty if the value cannot be converted to the desired type. This differs from .:? by attempting to parse Null the same as any other JSON value, instead of interpreting it as Nothing.
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.:!= ) :: FromJSON a => Object -> Key -> Parser aaeson Data.Aeson.Types Retrieve the value associated with the given key of an Object. If the key is not present and the omittedField is Just x for some x, the result will be that x. This differs from .:?= by attempting to parse Null the same as any other JSON value, instead of using omittedField when it's Just.
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.:? ) :: FromJSON a => Object -> Key -> Parser (Maybe a)aeson Data.Aeson.Types Retrieve the value associated with the given key of an Object. The result is Nothing if the key is not present or if its value is Null, or empty if the value cannot be converted to the desired type. This accessor is most useful if the key and value can be absent from an object without affecting its validity. If the key and value are mandatory, use .: instead.
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.:?= ) :: FromJSON a => Object -> Key -> Parser aaeson Data.Aeson.Types Retrieve the value associated with the given key of an Object. If the key is not present or the field is null and the omittedField is Just x for some x, the result will be that x.
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~: ) :: (HasCallStack, Testable t) => String -> t -> TestHUnit Test.HUnit.Base Creates a test from the specified Testable, with the specified label attached to it. Since Test is Testable, this can be used as a shorthand way of attaching a TestLabel to one or more tests.
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<<<>:= ) :: (MonadState s m, Semigroup r) => LensLike' ((,) r) s r -> r -> m rlens Control.Lens.Combinators (<>) a Semigroup value onto the front of the target of a Lens into your Monad's state and return the old result. However, unlike (<<<>=), it is prepended to the head side. When you do not need the result of the operation, (<>:=) is more flexible.
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<<<>:~ ) :: Semigroup m => LensLike' ((,) m) s m -> m -> s -> (m, s)lens Control.Lens.Combinators (<>) a Semigroup value onto the front of the target of a Lens and return the old result. However, unlike (<<>~), it is prepended to the head side. When you do not need the result of the operation, (<>:~) is more flexible.
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<<<>:= ) :: (MonadState s m, Semigroup r) => LensLike' ((,) r) s r -> r -> m rlens Control.Lens.Lens (<>) a Semigroup value onto the front of the target of a Lens into your Monad's state and return the old result. However, unlike (<<<>=), it is prepended to the head side. When you do not need the result of the operation, (<>:=) is more flexible.
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<<<>:~ ) :: Semigroup m => LensLike' ((,) m) s m -> m -> s -> (m, s)lens Control.Lens.Lens (<>) a Semigroup value onto the front of the target of a Lens and return the old result. However, unlike (<<>~), it is prepended to the head side. When you do not need the result of the operation, (<>:~) is more flexible.
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<<>:= ) :: (MonadState s m, Semigroup r) => LensLike' ((,) r) s r -> r -> m rlens Control.Lens.Lens (<>) a Semigroup value onto the front of the target of a Lens into your Monad's state and return the result. However, unlike (<<>=), it is prepended to the head side. When you do not need the result of the operation, (<>:=) is more flexible.