Copyright  (c) Fumiaki Kinoshita 2018 

License  BSD3 
Maintainer  Fumiaki Kinoshita <fumiexcel@gmail.com> 
Safe Haskell  None 
Language  Haskell2010 
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
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.
Wrapped Maybe
Nullable  

Instances
Wrapper h => Wrapper (Nullable h :: k > Type) Source #  
Eq (h x) => Eq (Nullable h x) Source #  
Ord (h x) => Ord (Nullable h x) Source #  
Defined in Data.Extensible.Nullable  
Show (h x) => Show (Nullable h x) Source #  
Generic (Nullable h x) Source #  
Semigroup (h x) => Semigroup (Nullable h x) Source #  
Semigroup (h x) => Monoid (Nullable h x) Source #  
Lift (h a) => Lift (Nullable h a) Source #  
Arbitrary (h x) => Arbitrary (Nullable h x) Source #  
Hashable (h x) => Hashable (Nullable h x) Source #  
Defined in Data.Extensible.Nullable  
Forall (KeyValue KnownSymbol (Instance1 ToJSON h)) xs => ToJSON (Nullable (Field h :: Assoc Symbol v > Type) :* xs) Source #  
Forall (KeyValue KnownSymbol (Instance1 FromJSON h)) xs => FromJSON (Nullable (Field h :: Assoc Symbol v > Type) :* xs) Source #  
NFData (h x) => NFData (Nullable h x) Source #  
Defined in Data.Extensible.Nullable  
type Repr (Nullable h :: k > Type) (x :: k) Source #  
type Rep (Nullable h x) Source #  
Defined in Data.Extensible.Nullable 
mapNullable :: (g x > h y) > Nullable g x > Nullable h y Source #
Apply a function to its content.