Be more explicit about kinds.

The aim here is to reduce the likelihood of failures due to kind mismatch in the future, as well as to help with documentation.
IntersectMBO · Oct 28, 2020 · 8c848fb · 8c848fb
1 parent e03d7bb
commit 8c848fb
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Showing 3 changed files with 10 additions and 4 deletions.
diff --git a/shelley-ma/impl/src/Cardano/Ledger/ShelleyMA.hs b/shelley-ma/impl/src/Cardano/Ledger/ShelleyMA.hs
@@ -1,6 +1,8 @@
 {-# LANGUAGE DataKinds #-}
+{-# LANGUAGE ExplicitForAll #-}
 {-# LANGUAGE TypeFamilies #-}
 {-# LANGUAGE UndecidableInstances #-}
+{-# OPTIONS_GHC -Wimplicit-kind-vars #-}
 
 module Cardano.Ledger.ShelleyMA where
 
@@ -24,13 +26,14 @@ data MaryOrAllegra = Mary | Allegra
 data ShelleyMAEra (ma :: MaryOrAllegra) c
 
 instance
+  forall c (ma :: MaryOrAllegra).
   (Typeable ma, Cardano.Ledger.Crypto.Crypto c) =>
   Era (ShelleyMAEra ma c)
   where
   type Crypto (ShelleyMAEra ma c) = c
 
 type family MAValue (x :: MaryOrAllegra) era :: Type where
-  MAValue 'Allegra era = Coin
+  MAValue 'Allegra _ = Coin
   MAValue 'Mary era = Value era
 
 type instance Core.Value (ShelleyMAEra m c) = MAValue m (ShelleyMAEra m c)
diff --git a/shelley-ma/impl/src/Cardano/Ledger/ShelleyMA/Rules/Utxo.hs b/shelley-ma/impl/src/Cardano/Ledger/ShelleyMA/Rules/Utxo.hs
@@ -255,9 +255,10 @@ utxoTransition = do
 --------------------------------------------------------------------------------
 
 instance
+  forall c (ma :: MaryOrAllegra).
   ( CryptoClass.Crypto c,
     Typeable ma,
-    ShelleyBased (ShelleyMAEra (ma :: MaryOrAllegra) c),
+    ShelleyBased (ShelleyMAEra ma c),
     Core.TxBody (ShelleyMAEra ma c) ~ TxBody (ShelleyMAEra ma c)
   ) =>
   STS (UTXO (ShelleyMAEra ma c))
@@ -277,7 +278,7 @@ instance
 
 instance
   (CryptoClass.Crypto c, Typeable ma) =>
-  Embed (PPUP (ShelleyMAEra ma c)) (UTXO (ShelleyMAEra ma c))
+  Embed (PPUP (ShelleyMAEra (ma :: MaryOrAllegra) c)) (UTXO (ShelleyMAEra ma c))
   where
   wrapFailed = UpdateFailure
 

diff --git a/shelley-ma/impl/src/Cardano/Ledger/ShelleyMA/Rules/Utxow.hs b/shelley-ma/impl/src/Cardano/Ledger/ShelleyMA/Rules/Utxow.hs
@@ -2,6 +2,7 @@
 {-# LANGUAGE FlexibleContexts #-}
 {-# LANGUAGE FlexibleInstances #-}
 {-# LANGUAGE MultiParamTypeClasses #-}
+{-# LANGUAGE ScopedTypeVariables #-}
 {-# LANGUAGE TypeApplications #-}
 {-# LANGUAGE TypeFamilies #-}
 {-# LANGUAGE UndecidableInstances #-}
@@ -15,7 +16,7 @@ import qualified Cardano.Ledger.Core as Core
 import qualified Cardano.Ledger.Crypto as CryptoClass
 import Cardano.Ledger.Mary.Value (PolicyID, Value, policies, policyID)
 import Cardano.Ledger.Shelley (ShelleyBased)
-import Cardano.Ledger.ShelleyMA (ShelleyMAEra)
+import Cardano.Ledger.ShelleyMA (MaryOrAllegra, ShelleyMAEra)
 import Cardano.Ledger.ShelleyMA.Scripts ()
 import Cardano.Ledger.ShelleyMA.TxBody ()
 import Cardano.Ledger.Val (Val)
@@ -113,6 +114,7 @@ scriptsNeeded u tx =
 --------------------------------------------------------------------------------
 
 instance
+  forall c (ma :: MaryOrAllegra).
   ( CryptoClass.Crypto c,
     Typeable ma,
     STS (UTXO (ShelleyMAEra ma c)),