X-Git-Url: http://git.megacz.com/?p=ghc-hetmet.git;a=blobdiff_plain;f=compiler%2FcoreSyn%2FExternalCore.lhs;h=359419ca0654a1f8f3da9479b60ead108cc10e1c;hp=d8eaa3ca6f6f0d90f6e46352daa67c5568dbf1b9;hb=b2524b3960999fffdb3767900f58825903f6560f;hpb=391a3e9c08c470bd1444cba2e5111e253c19ea84

diff --git a/compiler/coreSyn/ExternalCore.lhs b/compiler/coreSyn/ExternalCore.lhs
index d8eaa3c..359419c 100644
--- a/compiler/coreSyn/ExternalCore.lhs
+++ b/compiler/coreSyn/ExternalCore.lhs
@@ -4,13 +4,12 @@
 \begin{code}
 module ExternalCore where
 
-
 data Module 
  = Module Mname [Tdef] [Vdefg]
 
 data Tdef 
   = Data (Qual Tcon) [Tbind] [Cdef]
-  | Newtype (Qual Tcon) (Qual Tcon) [Tbind] (Maybe Ty)
+  | Newtype (Qual Tcon) (Qual Tcon) [Tbind] Ty
 
 data Cdef 
   = Constr (Qual Dcon) [Tbind] [Ty]
@@ -51,21 +50,21 @@ data Alt
 type Vbind = (Var,Ty)
 type Tbind = (Tvar,Kind)
 
+-- Internally, we represent types and coercions separately; but for
+-- the purposes of external core (at least for now) it's still
+-- convenient to collapse them into a single type.
 data Ty 
   = Tvar Tvar
   | 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.
+-- We distinguish primitive coercions 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
+  | NthCoercion Int Ty
 
 data Kind 
   = Klifted