Merge PR #27

kazu-yamamoto · Dec 3, 2023 · 90e1a0f · 90e1a0f
2 parents 46459d0 + d517cef
commit 90e1a0f
Showing 1 changed file with 5 additions and 2 deletions.
diff --git a/Crypto/Hash/Types.hs b/Crypto/Hash/Types.hs
@@ -7,9 +7,10 @@
 --
 -- Crypto hash types definitions
 --
-{-# LANGUAGE GeneralizedNewtypeDeriving #-}
-{-# LANGUAGE DeriveDataTypeable #-}
 {-# LANGUAGE DataKinds #-}
+{-# LANGUAGE DeriveDataTypeable #-}
+{-# LANGUAGE GeneralizedNewtypeDeriving #-}
+{-# LANGUAGE RoleAnnotations #-}
 {-# LANGUAGE ScopedTypeVariables #-}
 {-# LANGUAGE TypeFamilies #-}
 module Crypto.Hash.Types
@@ -97,6 +98,8 @@ newtype Context a = Context Bytes
 newtype Digest a = Digest (Block Word8)
     deriving (Eq,Ord,ByteArrayAccess, Data)
 
+type role Digest nominal
+
 instance NFData (Digest a) where
     rnf (Digest u) = u `deepseq` ()