    {-# LANGUAGE NoImplicitPrelude #-}
    {-# OPTIONS_HADDOCK not-home #-}

    -- | Maybe type
    module GHC.Maybe
       ( Maybe (..)
       )
    where

    import GHC.Num.Integer () -- See Note [Depend on GHC.Num.Integer] in GHC.Base
    import GHC.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.
    --
    data  Maybe a  =  Nothing | Just a
      deriving ( 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 -> Bool
    forall 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 -> Bool
    Eq  -- ^ @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 -> Bool
    Maybe a -> Maybe a -> Maybe a
    Maybe a -> Maybe a -> Ordering
    forall 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 a
    forall a. Ord a => Eq (Maybe a)
    forall a. Ord a => Maybe a -> Maybe a -> Bool
    forall a. Ord a => Maybe a -> Maybe a -> Maybe a
    forall a. Ord a => Maybe a -> Maybe a -> Ordering
    $ccompare :: forall a. Ord a => Maybe a -> Maybe a -> Ordering
    compare :: 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 a
    max :: Maybe a -> Maybe a -> Maybe a
    $cmin :: forall a. Ord a => Maybe a -> Maybe a -> Maybe a
    min :: Maybe a -> Maybe a -> Maybe a
    Ord -- ^ @since 2.01
               )