Added These data types

src/Plutarch/Api/V1/These.hs

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+{-# OPTIONS_GHC -Wno-orphans #-}
+
+module Plutarch.Api.V1.These (PTheseData (..)) where
+
+import GHC.Generics qualified as GHC
+import Generics.SOP
+import Plutarch.DataRepr (PIsDataReprInstances (PIsDataReprInstances))
+import Plutarch.Lift (
+  PConstantRepr,
+  PConstanted,
+  PLifted,
+  PUnsafeLiftDecl,
+  pconstantFromRepr,
+  pconstantToRepr,
+ )
+import Plutus.V1.Ledger.Api qualified as Plutus
+import PlutusTx.These qualified as PlutusThese
+
+data PTheseData (a :: PType) (b :: PType) (s :: S)
+  = PDThis (Term s (PDataRecord '["_0" ':= a]))
+  | PDThat (Term s (PDataRecord '["_0" ':= b]))
+  | PDThese (Term s (PDataRecord '["_0" ':= a, "_1" ':= b]))
+  deriving stock (GHC.Generic)
+  deriving anyclass (Generic, PIsDataRepr)
+  deriving
+    (PlutusType, PIsData)
+    via PIsDataReprInstances (PTheseData a b)
+
+instance
+  ( Plutus.ToData (PLifted a)
+  , Plutus.ToData (PLifted b)
+  , Plutus.FromData (PLifted a)
+  , Plutus.FromData (PLifted b)
+  , PLift a
+  , PLift b
+  ) =>
+  PUnsafeLiftDecl (PTheseData a b)
+  where
+  type PLifted (PTheseData a b) = PlutusThese.These (PLifted a) (PLifted b)
+
+{- TODO: Make PTheseData an instance of PConstant:
+         https://github.com/Plutonomicon/plutarch/pull/355
+-}
+
+instance
+  ( PLifted (PConstanted a) ~ a
+  , Plutus.ToData b
+  , Plutus.FromData b
+  , Plutus.ToData a
+  , Plutus.FromData a
+  , PConstant a
+  , PLifted (PConstanted b) ~ b
+  , Plutus.FromData b
+  , Plutus.ToData b
+  , PConstant b
+  ) =>
+  PConstant (PlutusThese.These a b)
+  where
+  type PConstantRepr (PlutusThese.These a b) = [(Plutus.Data, Plutus.Data)]
+  type PConstanted (PlutusThese.These a b) = PTheseData (PConstanted a) (PConstanted b)
+  pconstantToRepr _t = undefined
+  pconstantFromRepr _t = undefined

src/Plutarch/These.hs

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+module Plutarch.These (PThese (..)) where
+
+import GHC.Generics qualified as GHC
+import Generics.SOP
+
+-- | Plutus These type with Scott-encoded representation.
+data PThese (a :: PType) (b :: PType) (s :: S)
+  = PThis (Term s a)
+  | PThat (Term s b)
+  | PThese (Term s a) (Term s b)
+  deriving stock (GHC.Generic)
+  deriving anyclass (Generic, PlutusType)