Improve syntax for primitive coercions in External Core

[ghc-hetmet.git] / compiler / coreSyn / ExternalCore.lhs

diff --git a/compiler/coreSyn/ExternalCore.lhs b/compiler/coreSyn/ExternalCore.lhs
index a326a54..d8eaa3c 100644 (file)
--- a/compiler/coreSyn/ExternalCore.lhs
+++ b/compiler/coreSyn/ExternalCore.lhs
@@ -56,6 +56,16 @@ data Ty
   | Tcon (Qual Tcon)
   | Tapp Ty Ty
   | Tforall Tbind Ty 
+-- We distinguish primitive coercions
+-- (represented in GHC by wired-in names), because
+-- External Core treats them specially, so we have
+-- to print them out with special syntax.
+  | TransCoercion Ty Ty
+  | SymCoercion Ty
+  | UnsafeCoercion Ty Ty
+  | InstCoercion Ty Ty
+  | LeftCoercion Ty
+  | RightCoercion Ty
 
 data Kind 
   = Klifted