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{-# LANGUAGE NoImplicitPrelude #-}{-# OPTIONS_HADDOCK not-home #-}-- | Maybe typemoduleGHC.Maybe(Maybe(..))whereimportGHC.Num.Integer()-- See Note [Depend on GHC.Num.Integer] in GHC.BaseimportGHC.Classesdefault()--------------------------------------------------------------------------------- Maybe type--------------------------------------------------------------------------------- | The 'Maybe' type encapsulates an optional value. A value of type-- @'Maybe' a@ either contains a value of type @a@ (represented as @'Just' a@),-- or it is empty (represented as 'Nothing'). Using 'Maybe' is a good way to-- deal with errors or exceptional cases without resorting to drastic-- measures such as 'Prelude.error'.---- The 'Maybe' type is also a monad. It is a simple kind of error-- monad, where all errors are represented by 'Nothing'. A richer-- error monad can be built using the 'Data.Either.Either' type.--dataMaybea=Nothing|Justaderiving(Maybe a -> Maybe a -> Bool(Maybe a -> Maybe a -> Bool)-> (Maybe a -> Maybe a -> Bool) -> Eq (Maybe a)forall a. Eq a => Maybe a -> Maybe a -> Boolforall a. (a -> a -> Bool) -> (a -> a -> Bool) -> Eq a$c== :: forall a. Eq a => Maybe a -> Maybe a -> Bool== :: Maybe a -> Maybe a -> Bool$c/= :: forall a. Eq a => Maybe a -> Maybe a -> Bool/= :: Maybe a -> Maybe a -> BoolEq-- ^ @since 2.01,Eq (Maybe a)Eq (Maybe a) =>(Maybe a -> Maybe a -> Ordering)-> (Maybe a -> Maybe a -> Bool)-> (Maybe a -> Maybe a -> Bool)-> (Maybe a -> Maybe a -> Bool)-> (Maybe a -> Maybe a -> Bool)-> (Maybe a -> Maybe a -> Maybe a)-> (Maybe a -> Maybe a -> Maybe a)-> Ord (Maybe a)Maybe a -> Maybe a -> BoolMaybe a -> Maybe a -> Maybe aMaybe a -> Maybe a -> Orderingforall a.Eq a =>(a -> a -> Ordering)-> (a -> a -> Bool)-> (a -> a -> Bool)-> (a -> a -> Bool)-> (a -> a -> Bool)-> (a -> a -> a)-> (a -> a -> a)-> Ord aforall a. Ord a => Eq (Maybe a)forall a. Ord a => Maybe a -> Maybe a -> Boolforall a. Ord a => Maybe a -> Maybe a -> Maybe aforall a. Ord a => Maybe a -> Maybe a -> Ordering$ccompare :: forall a. Ord a => Maybe a -> Maybe a -> Orderingcompare :: Maybe a -> Maybe a -> Ordering$c< :: forall a. Ord a => Maybe a -> Maybe a -> Bool< :: Maybe a -> Maybe a -> Bool$c<= :: forall a. Ord a => Maybe a -> Maybe a -> Bool<= :: Maybe a -> Maybe a -> Bool$c> :: forall a. Ord a => Maybe a -> Maybe a -> Bool> :: Maybe a -> Maybe a -> Bool$c>= :: forall a. Ord a => Maybe a -> Maybe a -> Bool>= :: Maybe a -> Maybe a -> Bool$cmax :: forall a. Ord a => Maybe a -> Maybe a -> Maybe amax :: Maybe a -> Maybe a -> Maybe a$cmin :: forall a. Ord a => Maybe a -> Maybe a -> Maybe amin :: Maybe a -> Maybe a -> Maybe aOrd-- ^ @since 2.01)
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