src/Rel8/Schema/HTable/Maybe.hs · rel8

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1{-# LANGUAGE NamedFieldPuns #-}

2{-# LANGUAGE LambdaCase #-}

3{-# LANGUAGE TypeFamilies #-}

4{-# LANGUAGE KindSignatures #-}

5{-# language DataKinds #-}

6{-# language DeriveAnyClass #-}

7{-# language DeriveGeneric #-}

8{-# language DerivingStrategies #-}

9{-# language StandaloneKindSignatures #-}

11module Rel8.Schema.HTable.Maybe

12 ( HMaybeTable(..)

13 )

14where

16-- base

17import GHC.Generics ( Generic )

18import Prelude

20-- rel8

21import Rel8.Kind.Necessity ( Necessity( Required ) )

22import Rel8.Schema.HTable ( HTable )

23import Rel8.Schema.HTable.Identity ( HIdentity(..) )

24import qualified Rel8.Schema.Kind as K

25import Rel8.Schema.Spec ( Spec( Spec ) )

26import Rel8.Type.Tag ( MaybeTag )

27import Rel8.Schema.HTable.Nullify ( HNullify )

30type HMaybeTable :: K.HTable -> K.HTable

31data HMaybeTable table context = HMaybeTable

32 { htag :: HIdentity ('Spec '["isJust"] 'Required MaybeTag (Maybe MaybeTag)) context

33 , hjust :: HNullify table context

34 }

35 deriving stock Generic

36 deriving anyclass HTable