    {-# LANGUAGE CPP                #-}
    {-# LANGUAGE DeriveDataTypeable #-}
    module Distribution.Compat.NonEmptySet (
        NonEmptySet,
        -- * Construction
        singleton,
        -- * Insertion
        insert,
        -- * Deletion
        delete,
        -- * Conversions
        toNonEmpty,
        fromNonEmpty,
        toList,
        toSet,
        -- * Query
        member,
        -- * Map
        map,
    ) where

    import Prelude (Bool (..), Eq, Maybe (..), Ord (..), Read, Show (..), String, error, otherwise, return, showParen, showString, ($), (++), (.))

    import Control.DeepSeq    (NFData (..))
    import Data.Data          (Data)
    import Data.List.NonEmpty (NonEmpty (..))
    import Data.Semigroup     (Semigroup (..))
    import Data.Typeable      (Typeable)

    import qualified Data.Foldable as F
    import qualified Data.Set      as Set

    import Distribution.Compat.Binary    (Binary (..))
    import Distribution.Utils.Structured

    #if MIN_VERSION_binary(0,6,0)
    import Control.Applicative (empty)
    #else
    import Control.Monad (fail)
    #endif

    -- | @since 3.4.0.0
    newtype NonEmptySet a = NES (Set.Set a)
      deriving (NonEmptySet a -> NonEmptySet a -> Bool
    (NonEmptySet a -> NonEmptySet a -> Bool)
    -> (NonEmptySet a -> NonEmptySet a -> Bool) -> Eq (NonEmptySet a)
    forall a. Eq a => NonEmptySet a -> NonEmptySet a -> Bool
    forall a. (a -> a -> Bool) -> (a -> a -> Bool) -> Eq a
    $c== :: forall a. Eq a => NonEmptySet a -> NonEmptySet a -> Bool
    == :: NonEmptySet a -> NonEmptySet a -> Bool
    $c/= :: forall a. Eq a => NonEmptySet a -> NonEmptySet a -> Bool
    /= :: NonEmptySet a -> NonEmptySet a -> Bool
    Eq, Eq (NonEmptySet a)
    Eq (NonEmptySet a)
    -> (NonEmptySet a -> NonEmptySet a -> Ordering)
    -> (NonEmptySet a -> NonEmptySet a -> Bool)
    -> (NonEmptySet a -> NonEmptySet a -> Bool)
    -> (NonEmptySet a -> NonEmptySet a -> Bool)
    -> (NonEmptySet a -> NonEmptySet a -> Bool)
    -> (NonEmptySet a -> NonEmptySet a -> NonEmptySet a)
    -> (NonEmptySet a -> NonEmptySet a -> NonEmptySet a)
    -> Ord (NonEmptySet a)
    NonEmptySet a -> NonEmptySet a -> Bool
    NonEmptySet a -> NonEmptySet a -> Ordering
    NonEmptySet a -> NonEmptySet a -> NonEmptySet a
    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 (NonEmptySet a)
    forall a. Ord a => NonEmptySet a -> NonEmptySet a -> Bool
    forall a. Ord a => NonEmptySet a -> NonEmptySet a -> Ordering
    forall a. Ord a => NonEmptySet a -> NonEmptySet a -> NonEmptySet a
    $ccompare :: forall a. Ord a => NonEmptySet a -> NonEmptySet a -> Ordering
    compare :: NonEmptySet a -> NonEmptySet a -> Ordering
    $c< :: forall a. Ord a => NonEmptySet a -> NonEmptySet a -> Bool
    < :: NonEmptySet a -> NonEmptySet a -> Bool
    $c<= :: forall a. Ord a => NonEmptySet a -> NonEmptySet a -> Bool
    <= :: NonEmptySet a -> NonEmptySet a -> Bool
    $c> :: forall a. Ord a => NonEmptySet a -> NonEmptySet a -> Bool
    > :: NonEmptySet a -> NonEmptySet a -> Bool
    $c>= :: forall a. Ord a => NonEmptySet a -> NonEmptySet a -> Bool
    >= :: NonEmptySet a -> NonEmptySet a -> Bool
    $cmax :: forall a. Ord a => NonEmptySet a -> NonEmptySet a -> NonEmptySet a
    max :: NonEmptySet a -> NonEmptySet a -> NonEmptySet a
    $cmin :: forall a. Ord a => NonEmptySet a -> NonEmptySet a -> NonEmptySet a
    min :: NonEmptySet a -> NonEmptySet a -> NonEmptySet a
    Ord, Typeable, Typeable (NonEmptySet a)
    Typeable (NonEmptySet a)
    -> (forall (c :: * -> *).
        (forall d b. Data d => c (d -> b) -> d -> c b)
        -> (forall g. g -> c g) -> NonEmptySet a -> c (NonEmptySet a))
    -> (forall (c :: * -> *).
        (forall b r. Data b => c (b -> r) -> c r)
        -> (forall r. r -> c r) -> Constr -> c (NonEmptySet a))
    -> (NonEmptySet a -> Constr)
    -> (NonEmptySet a -> DataType)
    -> (forall (t :: * -> *) (c :: * -> *).
        Typeable t =>
        (forall d. Data d => c (t d)) -> Maybe (c (NonEmptySet a)))
    -> (forall (t :: * -> * -> *) (c :: * -> *).
        Typeable t =>
        (forall d e. (Data d, Data e) => c (t d e))
        -> Maybe (c (NonEmptySet a)))
    -> ((forall b. Data b => b -> b) -> NonEmptySet a -> NonEmptySet a)
    -> (forall r r'.
        (r -> r' -> r)
        -> r -> (forall d. Data d => d -> r') -> NonEmptySet a -> r)
    -> (forall r r'.
        (r' -> r -> r)
        -> r -> (forall d. Data d => d -> r') -> NonEmptySet a -> r)
    -> (forall u. (forall d. Data d => d -> u) -> NonEmptySet a -> [u])
    -> (forall u.
        Int -> (forall d. Data d => d -> u) -> NonEmptySet a -> u)
    -> (forall (m :: * -> *).
        Monad m =>
        (forall d. Data d => d -> m d)
        -> NonEmptySet a -> m (NonEmptySet a))
    -> (forall (m :: * -> *).
        MonadPlus m =>
        (forall d. Data d => d -> m d)
        -> NonEmptySet a -> m (NonEmptySet a))
    -> (forall (m :: * -> *).
        MonadPlus m =>
        (forall d. Data d => d -> m d)
        -> NonEmptySet a -> m (NonEmptySet a))
    -> Data (NonEmptySet a)
    NonEmptySet a -> Constr
    NonEmptySet a -> DataType
    (forall b. Data b => b -> b) -> NonEmptySet a -> NonEmptySet a
    forall {a}. (Data a, Ord a) => Typeable (NonEmptySet a)
    forall a. (Data a, Ord a) => NonEmptySet a -> Constr
    forall a. (Data a, Ord a) => NonEmptySet a -> DataType
    forall a.
    (Data a, Ord a) =>
    (forall b. Data b => b -> b) -> NonEmptySet a -> NonEmptySet a
    forall a u.
    (Data a, Ord a) =>
    Int -> (forall d. Data d => d -> u) -> NonEmptySet a -> u
    forall a u.
    (Data a, Ord a) =>
    (forall d. Data d => d -> u) -> NonEmptySet a -> [u]
    forall a r r'.
    (Data a, Ord a) =>
    (r -> r' -> r)
    -> r -> (forall d. Data d => d -> r') -> NonEmptySet a -> r
    forall a r r'.
    (Data a, Ord a) =>
    (r' -> r -> r)
    -> r -> (forall d. Data d => d -> r') -> NonEmptySet a -> r
    forall a (m :: * -> *).
    (Data a, Ord a, Monad m) =>
    (forall d. Data d => d -> m d)
    -> NonEmptySet a -> m (NonEmptySet a)
    forall a (m :: * -> *).
    (Data a, Ord a, MonadPlus m) =>
    (forall d. Data d => d -> m d)
    -> NonEmptySet a -> m (NonEmptySet a)
    forall a (c :: * -> *).
    (Data a, Ord a) =>
    (forall b r. Data b => c (b -> r) -> c r)
    -> (forall r. r -> c r) -> Constr -> c (NonEmptySet a)
    forall a (c :: * -> *).
    (Data a, Ord a) =>
    (forall d b. Data d => c (d -> b) -> d -> c b)
    -> (forall g. g -> c g) -> NonEmptySet a -> c (NonEmptySet a)
    forall a (t :: * -> *) (c :: * -> *).
    (Data a, Ord a, Typeable t) =>
    (forall d. Data d => c (t d)) -> Maybe (c (NonEmptySet a))
    forall a (t :: * -> * -> *) (c :: * -> *).
    (Data a, Ord a, Typeable t) =>
    (forall d e. (Data d, Data e) => c (t d e))
    -> Maybe (c (NonEmptySet a))
    forall a.
    Typeable a
    -> (forall (c :: * -> *).
        (forall d b. Data d => c (d -> b) -> d -> c b)
        -> (forall g. g -> c g) -> a -> c a)
    -> (forall (c :: * -> *).
        (forall b r. Data b => c (b -> r) -> c r)
        -> (forall r. r -> c r) -> Constr -> c a)
    -> (a -> Constr)
    -> (a -> DataType)
    -> (forall (t :: * -> *) (c :: * -> *).
        Typeable t =>
        (forall d. Data d => c (t d)) -> Maybe (c a))
    -> (forall (t :: * -> * -> *) (c :: * -> *).
        Typeable t =>
        (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c a))
    -> ((forall b. Data b => b -> b) -> a -> a)
    -> (forall r r'.
        (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> a -> r)
    -> (forall r r'.
        (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> a -> r)
    -> (forall u. (forall d. Data d => d -> u) -> a -> [u])
    -> (forall u. Int -> (forall d. Data d => d -> u) -> a -> u)
    -> (forall (m :: * -> *).
        Monad m =>
        (forall d. Data d => d -> m d) -> a -> m a)
    -> (forall (m :: * -> *).
        MonadPlus m =>
        (forall d. Data d => d -> m d) -> a -> m a)
    -> (forall (m :: * -> *).
        MonadPlus m =>
        (forall d. Data d => d -> m d) -> a -> m a)
    -> Data a
    forall u. Int -> (forall d. Data d => d -> u) -> NonEmptySet a -> u
    forall u. (forall d. Data d => d -> u) -> NonEmptySet a -> [u]
    forall r r'.
    (r -> r' -> r)
    -> r -> (forall d. Data d => d -> r') -> NonEmptySet a -> r
    forall r r'.
    (r' -> r -> r)
    -> r -> (forall d. Data d => d -> r') -> NonEmptySet a -> r
    forall (m :: * -> *).
    Monad m =>
    (forall d. Data d => d -> m d)
    -> NonEmptySet a -> m (NonEmptySet a)
    forall (m :: * -> *).
    MonadPlus m =>
    (forall d. Data d => d -> m d)
    -> NonEmptySet a -> m (NonEmptySet a)
    forall (c :: * -> *).
    (forall b r. Data b => c (b -> r) -> c r)
    -> (forall r. r -> c r) -> Constr -> c (NonEmptySet a)
    forall (c :: * -> *).
    (forall d b. Data d => c (d -> b) -> d -> c b)
    -> (forall g. g -> c g) -> NonEmptySet a -> c (NonEmptySet a)
    forall (t :: * -> *) (c :: * -> *).
    Typeable t =>
    (forall d. Data d => c (t d)) -> Maybe (c (NonEmptySet a))
    forall (t :: * -> * -> *) (c :: * -> *).
    Typeable t =>
    (forall d e. (Data d, Data e) => c (t d e))
    -> Maybe (c (NonEmptySet a))
    $cgfoldl :: forall a (c :: * -> *).
    (Data a, Ord a) =>
    (forall d b. Data d => c (d -> b) -> d -> c b)
    -> (forall g. g -> c g) -> NonEmptySet a -> c (NonEmptySet a)
    gfoldl :: forall (c :: * -> *).
    (forall d b. Data d => c (d -> b) -> d -> c b)
    -> (forall g. g -> c g) -> NonEmptySet a -> c (NonEmptySet a)
    $cgunfold :: forall a (c :: * -> *).
    (Data a, Ord a) =>
    (forall b r. Data b => c (b -> r) -> c r)
    -> (forall r. r -> c r) -> Constr -> c (NonEmptySet a)
    gunfold :: forall (c :: * -> *).
    (forall b r. Data b => c (b -> r) -> c r)
    -> (forall r. r -> c r) -> Constr -> c (NonEmptySet a)
    $ctoConstr :: forall a. (Data a, Ord a) => NonEmptySet a -> Constr
    toConstr :: NonEmptySet a -> Constr
    $cdataTypeOf :: forall a. (Data a, Ord a) => NonEmptySet a -> DataType
    dataTypeOf :: NonEmptySet a -> DataType
    $cdataCast1 :: forall a (t :: * -> *) (c :: * -> *).
    (Data a, Ord a, Typeable t) =>
    (forall d. Data d => c (t d)) -> Maybe (c (NonEmptySet a))
    dataCast1 :: forall (t :: * -> *) (c :: * -> *).
    Typeable t =>
    (forall d. Data d => c (t d)) -> Maybe (c (NonEmptySet a))
    $cdataCast2 :: forall a (t :: * -> * -> *) (c :: * -> *).
    (Data a, Ord a, Typeable t) =>
    (forall d e. (Data d, Data e) => c (t d e))
    -> Maybe (c (NonEmptySet a))
    dataCast2 :: forall (t :: * -> * -> *) (c :: * -> *).
    Typeable t =>
    (forall d e. (Data d, Data e) => c (t d e))
    -> Maybe (c (NonEmptySet a))
    $cgmapT :: forall a.
    (Data a, Ord a) =>
    (forall b. Data b => b -> b) -> NonEmptySet a -> NonEmptySet a
    gmapT :: (forall b. Data b => b -> b) -> NonEmptySet a -> NonEmptySet a
    $cgmapQl :: forall a r r'.
    (Data a, Ord a) =>
    (r -> r' -> r)
    -> r -> (forall d. Data d => d -> r') -> NonEmptySet a -> r
    gmapQl :: forall r r'.
    (r -> r' -> r)
    -> r -> (forall d. Data d => d -> r') -> NonEmptySet a -> r
    $cgmapQr :: forall a r r'.
    (Data a, Ord a) =>
    (r' -> r -> r)
    -> r -> (forall d. Data d => d -> r') -> NonEmptySet a -> r
    gmapQr :: forall r r'.
    (r' -> r -> r)
    -> r -> (forall d. Data d => d -> r') -> NonEmptySet a -> r
    $cgmapQ :: forall a u.
    (Data a, Ord a) =>
    (forall d. Data d => d -> u) -> NonEmptySet a -> [u]
    gmapQ :: forall u. (forall d. Data d => d -> u) -> NonEmptySet a -> [u]
    $cgmapQi :: forall a u.
    (Data a, Ord a) =>
    Int -> (forall d. Data d => d -> u) -> NonEmptySet a -> u
    gmapQi :: forall u. Int -> (forall d. Data d => d -> u) -> NonEmptySet a -> u
    $cgmapM :: forall a (m :: * -> *).
    (Data a, Ord a, Monad m) =>
    (forall d. Data d => d -> m d)
    -> NonEmptySet a -> m (NonEmptySet a)
    gmapM :: forall (m :: * -> *).
    Monad m =>
    (forall d. Data d => d -> m d)
    -> NonEmptySet a -> m (NonEmptySet a)
    $cgmapMp :: forall a (m :: * -> *).
    (Data a, Ord a, MonadPlus m) =>
    (forall d. Data d => d -> m d)
    -> NonEmptySet a -> m (NonEmptySet a)
    gmapMp :: forall (m :: * -> *).
    MonadPlus m =>
    (forall d. Data d => d -> m d)
    -> NonEmptySet a -> m (NonEmptySet a)
    $cgmapMo :: forall a (m :: * -> *).
    (Data a, Ord a, MonadPlus m) =>
    (forall d. Data d => d -> m d)
    -> NonEmptySet a -> m (NonEmptySet a)
    gmapMo :: forall (m :: * -> *).
    MonadPlus m =>
    (forall d. Data d => d -> m d)
    -> NonEmptySet a -> m (NonEmptySet a)
    Data, ReadPrec [NonEmptySet a]
    ReadPrec (NonEmptySet a)
    Int -> ReadS (NonEmptySet a)
    ReadS [NonEmptySet a]
    (Int -> ReadS (NonEmptySet a))
    -> ReadS [NonEmptySet a]
    -> ReadPrec (NonEmptySet a)
    -> ReadPrec [NonEmptySet a]
    -> Read (NonEmptySet a)
    forall a. (Read a, Ord a) => ReadPrec [NonEmptySet a]
    forall a. (Read a, Ord a) => ReadPrec (NonEmptySet a)
    forall a. (Read a, Ord a) => Int -> ReadS (NonEmptySet a)
    forall a. (Read a, Ord a) => ReadS [NonEmptySet a]
    forall a.
    (Int -> ReadS a)
    -> ReadS [a] -> ReadPrec a -> ReadPrec [a] -> Read a
    $creadsPrec :: forall a. (Read a, Ord a) => Int -> ReadS (NonEmptySet a)
    readsPrec :: Int -> ReadS (NonEmptySet a)
    $creadList :: forall a. (Read a, Ord a) => ReadS [NonEmptySet a]
    readList :: ReadS [NonEmptySet a]
    $creadPrec :: forall a. (Read a, Ord a) => ReadPrec (NonEmptySet a)
    readPrec :: ReadPrec (NonEmptySet a)
    $creadListPrec :: forall a. (Read a, Ord a) => ReadPrec [NonEmptySet a]
    readListPrec :: ReadPrec [NonEmptySet a]
    Read)

    -------------------------------------------------------------------------------
    -- Instances
    -------------------------------------------------------------------------------

    instance Show a => Show (NonEmptySet a) where
        showsPrec :: Int -> NonEmptySet a -> ShowS
    showsPrec Int
    d NonEmptySet a
    s = Bool -> ShowS -> ShowS
    showParen (Int
    d Int -> Int -> Bool
    forall a. Ord a => a -> a -> Bool
    > Int
    10)
            (ShowS -> ShowS) -> ShowS -> ShowS
    forall a b. (a -> b) -> a -> b
    $ String -> ShowS
    showString String
    "fromNonEmpty "
            ShowS -> ShowS -> ShowS
    forall b c a. (b -> c) -> (a -> b) -> a -> c
    . Int -> NonEmpty a -> ShowS
    forall a. Show a => Int -> a -> ShowS
    showsPrec Int
    11 (NonEmptySet a -> NonEmpty a
    forall a. NonEmptySet a -> NonEmpty a
    toNonEmpty NonEmptySet a
    s)

    instance Binary a => Binary (NonEmptySet a) where
        put :: NonEmptySet a -> Put
    put (NES Set a
    s) = Set a -> Put
    forall t. Binary t => t -> Put
    put Set a
    s
        get :: Get (NonEmptySet a)
    get = do
            Set a
    xs <- Get (Set a)
    forall t. Binary t => Get t
    get
            if Set a -> Bool
    forall a. Set a -> Bool
    Set.null Set a
    xs
    #if MIN_VERSION_binary(0,6,0)
            then Get (NonEmptySet a)
    forall a. Get a
    forall (f :: * -> *) a. Alternative f => f a
    empty
    #else
            then fail "NonEmptySet: empty"
    #endif
            else NonEmptySet a -> Get (NonEmptySet a)
    forall a. a -> Get a
    forall (m :: * -> *) a. Monad m => a -> m a
    return (Set a -> NonEmptySet a
    forall a. Set a -> NonEmptySet a
    NES Set a
    xs)

    instance Structured a => Structured (NonEmptySet a) where
        structure :: Proxy (NonEmptySet a) -> Structure
    structure = Proxy (NonEmptySet a) -> Structure
    forall {k} (f :: * -> k) a.
    (Typeable f, Structured a) =>
    Proxy (f a) -> Structure
    containerStructure

    instance NFData a => NFData (NonEmptySet a) where
        rnf :: NonEmptySet a -> ()
    rnf (NES Set a
    x) = Set a -> ()
    forall a. NFData a => a -> ()
    rnf Set a
    x

    -- | Note: there aren't @Monoid@ instance.
    instance Ord a => Semigroup (NonEmptySet a) where
        NES Set a
    x <> :: NonEmptySet a -> NonEmptySet a -> NonEmptySet a
    <> NES Set a
    y = Set a -> NonEmptySet a
    forall a. Set a -> NonEmptySet a
    NES (Set a -> Set a -> Set a
    forall a. Ord a => Set a -> Set a -> Set a
    Set.union Set a
    x Set a
    y)

    instance F.Foldable NonEmptySet where
        foldMap :: forall m a. Monoid m => (a -> m) -> NonEmptySet a -> m
    foldMap a -> m
    f (NES Set a
    s) = (a -> m) -> Set a -> m
    forall m a. Monoid m => (a -> m) -> Set a -> m
    forall (t :: * -> *) m a.
    (Foldable t, Monoid m) =>
    (a -> m) -> t a -> m
    F.foldMap a -> m
    f Set a
    s
        foldr :: forall a b. (a -> b -> b) -> b -> NonEmptySet a -> b
    foldr a -> b -> b
    f b
    z (NES Set a
    s) = (a -> b -> b) -> b -> Set a -> b
    forall a b. (a -> b -> b) -> b -> Set a -> b
    forall (t :: * -> *) a b.
    Foldable t =>
    (a -> b -> b) -> b -> t a -> b
    F.foldr a -> b -> b
    f b
    z Set a
    s

    #if MIN_VERSION_base(4,8,0)
        toList :: forall a. NonEmptySet a -> [a]
    toList         = NonEmptySet a -> [a]
    forall a. NonEmptySet a -> [a]
    toList
        null :: forall a. NonEmptySet a -> Bool
    null NonEmptySet a
    _         = Bool
    False
        length :: forall a. NonEmptySet a -> Int
    length (NES Set a
    s) = Set a -> Int
    forall a. Set a -> Int
    forall (t :: * -> *) a. Foldable t => t a -> Int
    F.length Set a
    s
    #endif

    -------------------------------------------------------------------------------
    -- Constructors
    -------------------------------------------------------------------------------

    singleton :: a -> NonEmptySet a
    singleton :: forall a. a -> NonEmptySet a
    singleton = Set a -> NonEmptySet a
    forall a. Set a -> NonEmptySet a
    NES (Set a -> NonEmptySet a) -> (a -> Set a) -> a -> NonEmptySet a
    forall b c a. (b -> c) -> (a -> b) -> a -> c
    . a -> Set a
    forall a. a -> Set a
    Set.singleton

    -------------------------------------------------------------------------------
    -- Insertion
    -------------------------------------------------------------------------------

    insert :: Ord a => a -> NonEmptySet a -> NonEmptySet a
    insert :: forall a. Ord a => a -> NonEmptySet a -> NonEmptySet a
    insert a
    x (NES Set a
    xs) = Set a -> NonEmptySet a
    forall a. Set a -> NonEmptySet a
    NES (a -> Set a -> Set a
    forall a. Ord a => a -> Set a -> Set a
    Set.insert a
    x Set a
    xs)

    -------------------------------------------------------------------------------
    -- Deletion
    -------------------------------------------------------------------------------

    delete :: Ord a => a -> NonEmptySet a -> Maybe (NonEmptySet a)
    delete :: forall a. Ord a => a -> NonEmptySet a -> Maybe (NonEmptySet a)
    delete a
    x (NES Set a
    xs)
        | Set a -> Bool
    forall a. Set a -> Bool
    Set.null Set a
    res = Maybe (NonEmptySet a)
    forall a. Maybe a
    Nothing
        | Bool
    otherwise    = NonEmptySet a -> Maybe (NonEmptySet a)
    forall a. a -> Maybe a
    Just (Set a -> NonEmptySet a
    forall a. Set a -> NonEmptySet a
    NES Set a
    xs)
      where
        res :: Set a
    res = a -> Set a -> Set a
    forall a. Ord a => a -> Set a -> Set a
    Set.delete a
    x Set a
    xs

    -------------------------------------------------------------------------------
    -- Conversions
    -------------------------------------------------------------------------------

    fromNonEmpty :: Ord a => NonEmpty a -> NonEmptySet a
    fromNonEmpty :: forall a. Ord a => NonEmpty a -> NonEmptySet a
    fromNonEmpty (a
    x :| [a]
    xs) = Set a -> NonEmptySet a
    forall a. Set a -> NonEmptySet a
    NES ([a] -> Set a
    forall a. Ord a => [a] -> Set a
    Set.fromList (a
    x a -> [a] -> [a]
    forall a. a -> [a] -> [a]
    : [a]
    xs))

    toNonEmpty :: NonEmptySet a -> NonEmpty a
    toNonEmpty :: forall a. NonEmptySet a -> NonEmpty a
    toNonEmpty (NES Set a
    s) = case Set a -> [a]
    forall a. Set a -> [a]
    Set.toList Set a
    s of
        []   -> String -> NonEmpty a
    forall a. String -> a
    panic String
    "toNonEmpty"
        a
    x:[a]
    xs -> a
    x a -> [a] -> NonEmpty a
    forall a. a -> [a] -> NonEmpty a
    :| [a]
    xs

    toList :: NonEmptySet a -> [a]
    toList :: forall a. NonEmptySet a -> [a]
    toList (NES Set a
    s) = Set a -> [a]
    forall a. Set a -> [a]
    Set.toList Set a
    s

    toSet :: NonEmptySet a -> Set.Set a
    toSet :: forall a. NonEmptySet a -> Set a
    toSet (NES Set a
    s) = Set a
    s

    -------------------------------------------------------------------------------
    -- Query
    -------------------------------------------------------------------------------

    member :: Ord a => a -> NonEmptySet a -> Bool
    member :: forall a. Ord a => a -> NonEmptySet a -> Bool
    member a
    x (NES Set a
    xs) = a -> Set a -> Bool
    forall a. Ord a => a -> Set a -> Bool
    Set.member a
    x Set a
    xs

    -------------------------------------------------------------------------------
    -- Map
    -------------------------------------------------------------------------------

    map
        :: ( Ord b
    #if !MIN_VERSION_containers(0,5,2)
           , Ord a
    #endif
           )
        => (a -> b) -> NonEmptySet a -> NonEmptySet b
    map :: forall b a. Ord b => (a -> b) -> NonEmptySet a -> NonEmptySet b
    map a -> b
    f (NES Set a
    x) = Set b -> NonEmptySet b
    forall a. Set a -> NonEmptySet a
    NES ((a -> b) -> Set a -> Set b
    forall b a. Ord b => (a -> b) -> Set a -> Set b
    Set.map a -> b
    f Set a
    x)

    -------------------------------------------------------------------------------
    -- Internal
    -------------------------------------------------------------------------------

    panic :: String -> a
    panic :: forall a. String -> a
    panic String
    msg = String -> a
    forall a. HasCallStack => String -> a
    error (String -> a) -> String -> a
    forall a b. (a -> b) -> a -> b
    $ String
    "NonEmptySet invariant violated: " String -> ShowS
    forall a. [a] -> [a] -> [a]
    ++ String
    msg