{-# LANGUAGE NoImplicitPrelude #-}{-# OPTIONS_HADDOCK not-home #-}-- | Maybe typemoduleGHC.Maybe(Maybe (..))whereimportGHC.Num.Integer ()-- See Note [Depend on GHC.Num.Integer] in GHC.BaseimportGHC.Classes default()--------------------------------------------------------------------------------- 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.--dataMaybe a =Nothing |Just a deriving(Maybe a -> Maybe a -> Bool
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