Rename the Byron, Shelley etc types to be clearly eras

So rename ByronEra -> ByronEra, Shelley to ShelleyEra etc

This first step adds the new names, and keeps deprecated aliases for the
previous names.

The purpose of this renaming is because we want to clarify that these
type tags are really used to indicate an era.

Where we are tempted to use them for something other than eras then we
need new names. For example we have Byron and Shelley address types,
which are not quite the same as the Byron and Shelley era, since both
address types are available in the Shelley and all subsequent eras. So
we will want to introduce new names such as ByronAddr/ShelleyAddr and
use those rather than ByronEra/ShelleyEra for types of addresses.

cardano-api/src/Cardano/API.hs

@@ -11,6 +11,17 @@
 --
 
 module Cardano.API (
+    -- * Eras
+    ByronEra,
+    ShelleyEra,
+    AllegraEra,
+    MaryEra,
+    -- ** Deprecated
+    Byron,
+    Shelley,
+    Allegra,
+    Mary,
+    -- * Type tags
     HasTypeProxy(..),
     AsType(..),
     -- * Cryptographic key interface

cardano-api/src/Cardano/Api/Byron.hs

@@ -5,16 +5,6 @@
 
 module Cardano.Api.Byron
   ( module Cardano.API,
-    -- * Era
-    Byron,
-    HasTypeProxy(..),
-    AsType
-      ( AsByronAddress
-      , AsByronKey
-      , AsByronTx
-      , AsByronTxBody
-      , AsByronWitness
-      ),
 
     -- * Cryptographic key interface
     -- $keys

cardano-api/src/Cardano/Api/Eras.hs

@@ -1,47 +1,89 @@
 {-# LANGUAGE GADTs #-}
 {-# LANGUAGE TypeFamilies #-}
+{-# LANGUAGE PatternSynonyms #-}
 
 
 -- | Cardano eras, sometimes we have to distinguish them.
 --
 module Cardano.Api.Eras
   ( -- * Eras
-    Byron
+    ByronEra
+  , ShelleyEra
+  , AllegraEra
+  , MaryEra
+
+    -- * Deprecated aliases
+  , Byron
   , Shelley
   , Allegra
   , Mary
-  , AsType(..)
+
+    -- * Data family instances
+  , AsType(AsByronEra, AsShelleyEra, AsAllegraEra, AsMaryEra,
+           AsByron,    AsShelley,    AsAllegra,    AsMary)
   ) where
 
 import           Cardano.Api.HasTypeProxy
 
 
 -- | A type used as a tag to distinguish the Byron era.
-data Byron
+data ByronEra
 
 -- | A type used as a tag to distinguish the Shelley era.
-data Shelley
+data ShelleyEra
 
 -- | A type used as a tag to distinguish the Allegra era.
-data Allegra
+data AllegraEra
 
 -- | A type used as a tag to distinguish the Mary era.
-data Mary
+data MaryEra
+
+
+instance HasTypeProxy ByronEra where
+    data AsType ByronEra = AsByronEra
+    proxyToAsType _ = AsByronEra
+
+instance HasTypeProxy ShelleyEra where
+    data AsType ShelleyEra = AsShelleyEra
+    proxyToAsType _ = AsShelleyEra
+
+instance HasTypeProxy AllegraEra where
+    data AsType AllegraEra = AsAllegraEra
+    proxyToAsType _ = AsAllegraEra
+
+instance HasTypeProxy MaryEra where
+    data AsType MaryEra = AsMaryEra
+    proxyToAsType _ = AsMaryEra
+
+
+-- ----------------------------------------------------------------------------
+-- Deprecated aliases
+--
+
+type Byron   = ByronEra
+type Shelley = ShelleyEra
+type Allegra = AllegraEra
+type Mary    = MaryEra
+
+{-# DEPRECATED Byron   "Use 'ByronEra' or 'ByronAddr' as appropriate" #-}
+{-# DEPRECATED Shelley "Use 'ShelleyEra' or 'ShelleyAddr' as appropriate" #-}
+{-# DEPRECATED Allegra "Use 'AllegraEra' instead" #-}
+{-# DEPRECATED Mary    "Use 'MaryEra' instead" #-}
 
+pattern AsByron   :: AsType ByronEra
+pattern AsByron    = AsByronEra
 
-instance HasTypeProxy Byron where
-    data AsType Byron = AsByron
-    proxyToAsType _ = AsByron
+pattern AsShelley :: AsType ShelleyEra
+pattern AsShelley  = AsShelleyEra
 
-instance HasTypeProxy Shelley where
-    data AsType Shelley = AsShelley
-    proxyToAsType _ = AsShelley
+pattern AsAllegra :: AsType AllegraEra
+pattern AsAllegra  = AsAllegraEra
 
-instance HasTypeProxy Allegra where
-    data AsType Allegra = AsAllegra
-    proxyToAsType _ = AsAllegra
+pattern AsMary    :: AsType MaryEra
+pattern AsMary     = AsMaryEra
 
-instance HasTypeProxy Mary where
-    data AsType Mary = AsMary
-    proxyToAsType _ = AsMary
+{-# DEPRECATED AsByron   "Use 'AsByronEra' instead" #-}
+{-# DEPRECATED AsShelley "Use 'AsShelleyEra' instead" #-}
+{-# DEPRECATED AsAllegra "Use 'AsAllegraEra' instead" #-}
+{-# DEPRECATED AsMary    "Use 'AsMaryEra' instead" #-}
 

cardano-api/src/Cardano/Api/Shelley.hs

@@ -5,13 +5,6 @@
 
 module Cardano.Api.Shelley
   ( module Cardano.API,
-    -- * Era
-    Shelley,
-    HasTypeProxy(..),
-    AsType(AsShelleyAddress,
-           AsShelleyTxBody,
-           AsShelleyTx,
-           AsShelleyWitness),
 
     -- * Cryptographic key interface
     -- $keys

cardano-api/src/Cardano/Api/Typed.hs

@@ -26,10 +26,16 @@
 --
 module Cardano.Api.Typed (
     -- * Eras
+    ByronEra,
+    ShelleyEra,
+    AllegraEra,
+    MaryEra,
+    -- ** Deprecated
     Byron,
     Shelley,
     Allegra,
     Mary,
+    -- * Type tags
     HasTypeProxy(..),
     AsType(..),
     -- * Cryptographic key interface