Introduce ChainData, SerialisableData, and AnnotatedData

These constraint synonyms make the contexts of the API classes much more
readable.

shelley/chain-and-ledger/executable-spec/src/Cardano/Ledger/API/Mempool.hs

@@ -17,8 +17,9 @@ module Cardano.Ledger.API.Mempool
   )
 where
 
-import Cardano.Binary (Annotator, FromCBOR (..), ToCBOR (..))
+import Cardano.Binary (FromCBOR (..), ToCBOR (..))
 import Cardano.Crypto.Hash (Hash)
+import Cardano.Ledger.Core (AnnotatedData, SerialisableData, ChainData)
 import Cardano.Ledger.Crypto (Crypto, HASH)
 import Cardano.Ledger.Shelley (ShelleyBased, ShelleyEra)
 import Control.Arrow (left)
@@ -32,7 +33,6 @@ import Control.State.Transition.Extended
   )
 import Data.Sequence (Seq)
 import Data.Typeable (Typeable)
-import NoThunks.Class (NoThunks)
 import Shelley.Spec.Ledger.BaseTypes (Globals)
 import Shelley.Spec.Ledger.Keys (DSignable)
 import Shelley.Spec.Ledger.LedgerState (NewEpochState)
@@ -45,16 +45,12 @@ import Shelley.Spec.Ledger.TxBody (EraIndependentTxBody)
 
 -- TODO #1304: add reapplyTxs
 class
-  ( Eq (Tx era),
-    Show (Tx era),
-    NoThunks (Tx era),
-    FromCBOR (Annotator (Tx era)),
-    ToCBOR (Tx era),
+  ( ChainData (Tx era),
+    AnnotatedData (Tx era),
     Eq (ApplyTxError era),
     Show (ApplyTxError era),
-    FromCBOR (ApplyTxError era),
-    ToCBOR (ApplyTxError era),
-    Typeable (ApplyTxError era)
+    Typeable (ApplyTxError era),
+    SerialisableData (ApplyTxError era)
   ) =>
   ApplyTx era
   where

shelley/chain-and-ledger/executable-spec/src/Cardano/Ledger/API/Protocol.hs

@@ -30,6 +30,7 @@ module Cardano.Ledger.API.Protocol
 where
 
 import Cardano.Binary (FromCBOR (..), ToCBOR (..), encodeListLen)
+import Cardano.Ledger.Core (SerialisableData, ChainData)
 import qualified Cardano.Ledger.Crypto as CC (Crypto)
 import Cardano.Ledger.Era (Crypto)
 import Cardano.Ledger.Shelley (ShelleyBased, ShelleyEra)
@@ -77,9 +78,8 @@ import Shelley.Spec.Ledger.Serialization (decodeRecordNamed)
 import Shelley.Spec.Ledger.Slot (SlotNo)
 
 class
-  ( Eq (ChainDepState (Crypto era)),
-    Show (ChainDepState (Crypto era)),
-    NoThunks (ChainDepState (Crypto era)),
+  ( ChainData (ChainDepState (Crypto era)),
+    SerialisableData (ChainDepState (Crypto era)),
     Eq (ChainTransitionError (Crypto era)),
     Show (ChainTransitionError (Crypto era)),
     Show (LedgerView (Crypto era)),

shelley/chain-and-ledger/executable-spec/src/Cardano/Ledger/API/Validation.hs

@@ -19,8 +19,8 @@ module Cardano.Ledger.API.Validation
   )
 where
 
-import Cardano.Binary (Annotator, FromCBOR (..), ToCBOR (..))
 import Cardano.Crypto.Hash (Hash)
+import Cardano.Ledger.Core (ChainData, SerialisableData, AnnotatedData)
 import Cardano.Ledger.Crypto (HASH)
 import qualified Cardano.Ledger.Crypto as CC (Crypto)
 import Cardano.Ledger.Era (Crypto, Era)
@@ -47,27 +47,14 @@ import Shelley.Spec.Ledger.TxBody (EraIndependentTxBody)
 -------------------------------------------------------------------------------}
 
 class
-  ( Eq (Block era),
-    Show (Block era),
-    NoThunks (Block era),
-    FromCBOR (Annotator (Block era)),
-    ToCBOR (Block era),
-    Eq (BHeader (Crypto era)),
-    Show (BHeader (Crypto era)),
-    NoThunks (BHeader (Crypto era)),
-    FromCBOR (Annotator (BHeader (Crypto era))),
-    ToCBOR (Block era),
-    Eq (NewEpochState era),
-    Show (NewEpochState era),
-    NoThunks (NewEpochState era),
-    FromCBOR (NewEpochState era),
-    ToCBOR (NewEpochState era),
-    Eq (BlockTransitionError era),
-    Show (BlockTransitionError era),
-    NoThunks (BlockTransitionError era),
-    Eq (STS.PredicateFailure (STS.CHAIN era)),
-    Show (STS.PredicateFailure (STS.CHAIN era)),
-    NoThunks (STS.PredicateFailure (STS.CHAIN era))
+  ( ChainData (Block era),
+    AnnotatedData (Block era),
+    ChainData (BHeader (Crypto era)),
+    AnnotatedData (BHeader (Crypto era)),
+    ChainData (NewEpochState era),
+    SerialisableData (NewEpochState era),
+    ChainData (BlockTransitionError era),
+    ChainData (STS.PredicateFailure (STS.CHAIN era))
   ) =>
   ApplyBlock era
   where

shelley/chain-and-ledger/executable-spec/src/Cardano/Ledger/Core.hs

@@ -1,3 +1,4 @@
+{-# LANGUAGE ConstraintKinds #-}
 {-# LANGUAGE FlexibleContexts #-}
 {-# LANGUAGE FlexibleInstances #-}
 {-# LANGUAGE TypeFamilies #-}
@@ -16,12 +17,17 @@ module Cardano.Ledger.Core
     Compact (..),
     TxBody,
     Value,
+    -- * Constraint synonyms
+    ChainData,
+    SerialisableData,
+    AnnotatedData,
   )
 where
 
-import Cardano.Binary (FromCBOR (..), ToCBOR (..))
+import Cardano.Binary (FromCBOR (..), ToCBOR (..), Annotator)
 import Data.Kind (Type)
 import Data.Typeable (Typeable)
+import NoThunks.Class (NoThunks)
 
 -- | A value is something which quantifies a transaction output.
 type family Value era :: Type
@@ -61,3 +67,19 @@ instance
 -- TODO: consider if this is better the other way around
 instance (Eq a, Compactible a) => Eq (CompactForm a) where
   a == b = fromCompact a == fromCompact b
+
+-------------------------------------------------------------------------------
+-- * Constraint synonyms
+-------------------------------------------------------------------------------
+
+-- | Common constraints
+--
+-- NOTE: 'Ord' is not included, as 'Ord' for a 'Block' or a 'NewEpochState'
+-- doesn't make sense.
+type ChainData t = (Eq t, Show t, NoThunks t, Typeable t)
+
+-- | Constraints for serialising from/to CBOR
+type SerialisableData t = (FromCBOR t, ToCBOR t)
+
+-- | Constraints for serialising from/to CBOR using 'Annotator'
+type AnnotatedData t = (FromCBOR (Annotator t), ToCBOR t)