Copyright	(c) Fumiaki Kinoshita 2018
License	BSD3
Maintainer	Fumiaki Kinoshita <fumiexcel@gmail.com>
Safe Haskell	None
Language	Haskell2010

Data.Extensible.Nullable

Description

Synopsis

vacancy :: Generate xs => Nullable h :* xs
coinclusion :: (Include ys xs, Generate ys) => Nullable (Membership xs) :* ys
wrench :: (Generate ys, xs ⊆ ys) => (h :* xs) -> Nullable h :* ys
retrench :: (Generate ys, xs ⊆ ys) => (h :| ys) -> Nullable ((:|) h) xs
newtype Nullable h x = Nullable {
- getNullable :: Maybe (h x)
}
mapNullable :: (g x -> h y) -> Nullable g x -> Nullable h y

Documentation

vacancy :: Generate xs => Nullable h :* xs Source #

A product filled with Nullable Nothing

coinclusion :: (Include ys xs, Generate ys) => Nullable (Membership xs) :* ys Source #

The inverse of inclusion.

wrench :: (Generate ys, xs ⊆ ys) => (h :* xs) -> Nullable h :* ys Source #

Extend a product and fill missing fields by Null.

retrench :: (Generate ys, xs ⊆ ys) => (h :| ys) -> Nullable ((:|) h) xs Source #

Narrow the range of the sum, if possible.

newtype Nullable h x Source #

Wrapped Maybe

Constructors

Nullable
Fields getNullable :: Maybe (h x)

Instances

Wrapper h => Wrapper (Nullable h :: k -> Type) Source #
Instance details Defined in Data.Extensible.Nullable Associated Types type Repr (Nullable h) v :: Type Source # Methods _Wrapper :: (Functor f, Profunctor p) => Optic' p f (Nullable h v) (Repr (Nullable h) v) Source # wrap :: Repr (Nullable h) v -> Nullable h v Source # unwrap :: Nullable h v -> Repr (Nullable h) v Source #
Eq (h x) => Eq (Nullable h x) Source #
Instance details Defined in Data.Extensible.Nullable Methods (==) :: Nullable h x -> Nullable h x -> Bool # (/=) :: Nullable h x -> Nullable h x -> Bool #
Ord (h x) => Ord (Nullable h x) Source #
Instance details Defined in Data.Extensible.Nullable Methods compare :: Nullable h x -> Nullable h x -> Ordering # (<) :: Nullable h x -> Nullable h x -> Bool # (<=) :: Nullable h x -> Nullable h x -> Bool # (>) :: Nullable h x -> Nullable h x -> Bool # (>=) :: Nullable h x -> Nullable h x -> Bool # max :: Nullable h x -> Nullable h x -> Nullable h x # min :: Nullable h x -> Nullable h x -> Nullable h x #
Show (h x) => Show (Nullable h x) Source #
Instance details Defined in Data.Extensible.Nullable Methods showsPrec :: Int -> Nullable h x -> ShowS # show :: Nullable h x -> String # showList :: [Nullable h x] -> ShowS #
Generic (Nullable h x) Source #
Instance details Defined in Data.Extensible.Nullable Associated Types type Rep (Nullable h x) :: Type -> Type # Methods from :: Nullable h x -> Rep (Nullable h x) x0 # to :: Rep (Nullable h x) x0 -> Nullable h x #
Semigroup (h x) => Semigroup (Nullable h x) Source #
Instance details Defined in Data.Extensible.Nullable Methods (<>) :: Nullable h x -> Nullable h x -> Nullable h x # sconcat :: NonEmpty (Nullable h x) -> Nullable h x # stimes :: Integral b => b -> Nullable h x -> Nullable h x #
Semigroup (h x) => Monoid (Nullable h x) Source #
Instance details Defined in Data.Extensible.Nullable Methods mempty :: Nullable h x # mappend :: Nullable h x -> Nullable h x -> Nullable h x # mconcat :: [Nullable h x] -> Nullable h x #
Lift (h a) => Lift (Nullable h a) Source #
Instance details Defined in Data.Extensible.Nullable Methods lift :: Nullable h a -> Q Exp #
Arbitrary (h x) => Arbitrary (Nullable h x) Source #
Instance details Defined in Data.Extensible.Nullable Methods arbitrary :: Gen (Nullable h x) # shrink :: Nullable h x -> [Nullable h x] #
Hashable (h x) => Hashable (Nullable h x) Source #
Instance details Defined in Data.Extensible.Nullable Methods hashWithSalt :: Int -> Nullable h x -> Int # hash :: Nullable h x -> Int #
Forall (KeyValue KnownSymbol (Instance1 ToJSON h)) xs => ToJSON (Nullable (Field h :: Assoc Symbol v -> Type) :* xs) Source #
Instance details Defined in Data.Extensible.Dictionary Methods toJSON :: (Nullable (Field h) :* xs) -> Value # toEncoding :: (Nullable (Field h) :* xs) -> Encoding # toJSONList :: [Nullable (Field h) :* xs] -> Value # toEncodingList :: [Nullable (Field h) :* xs] -> Encoding #
Forall (KeyValue KnownSymbol (Instance1 FromJSON h)) xs => FromJSON (Nullable (Field h :: Assoc Symbol v -> Type) :* xs) Source #
Instance details Defined in Data.Extensible.Dictionary Methods parseJSON :: Value -> Parser (Nullable (Field h) :* xs) # parseJSONList :: Value -> Parser [Nullable (Field h) :* xs] #
NFData (h x) => NFData (Nullable h x) Source #
Instance details Defined in Data.Extensible.Nullable Methods rnf :: Nullable h x -> () #
type Repr (Nullable h :: k -> Type) (x :: k) Source #
Instance details Defined in Data.Extensible.Nullable type Repr (Nullable h :: k -> Type) (x :: k) = Maybe (Repr h x)
type Rep (Nullable h x) Source #
Instance details Defined in Data.Extensible.Nullable type Rep (Nullable h x) = D1 (MetaData "Nullable" "Data.Extensible.Nullable" "extensible-0.5-HtYa3fOZlWC7KXWLoStAWc" True) (C1 (MetaCons "Nullable" PrefixI True) (S1 (MetaSel (Just "getNullable") NoSourceUnpackedness NoSourceStrictness DecidedLazy) (Rec0 (Maybe (h x)))))

mapNullable :: (g x -> h y) -> Nullable g x -> Nullable h y Source #

Apply a function to its content.