Introduce coercions for data instance decls

[ghc-hetmet.git] / compiler / iface / TcIface.lhs

diff --git a/compiler/iface/TcIface.lhs b/compiler/iface/TcIface.lhs
index 08dfe8c..2831c2d 100644 (file)
--- a/compiler/iface/TcIface.lhs
+++ b/compiler/iface/TcIface.lhs
@@ -30,7 +30,8 @@ import Type           ( liftedTypeKind, splitTyConApp, mkTyConApp,
                           ubxTupleKindTyCon,
                          mkTyVarTys, ThetaType )
 import TypeRep         ( Type(..), PredType(..) )
-import TyCon           ( TyCon, tyConName, SynTyConRhs(..) )
+import TyCon           ( TyCon, tyConName, SynTyConRhs(..), 
+                         AlgTyConParent(..) )
 import HscTypes                ( ExternalPackageState(..), 
                          TyThing(..), tyThingClass, tyThingTyCon, 
                          ModIface(..), ModDetails(..), HomeModInfo(..),
@@ -68,6 +69,7 @@ import SrcLoc         ( noSrcLoc )
 import Util            ( zipWithEqual, equalLength, splitAtList )
 import DynFlags                ( DynFlag(..), isOneShot )
 
+import Monad           ( liftM )
 \end{code}
 
 This module takes
@@ -358,15 +360,24 @@ tcIfaceDecl (IfaceData {ifName = occ_name,
                        ifCtxt = ctxt, ifGadtSyntax = gadt_syn,
                        ifCons = rdr_cons, 
                        ifRec = is_rec, 
-                       ifGeneric = want_generic })
+                       ifGeneric = want_generic,
+                       ifFamInst = mb_family })
   = do { tc_name <- lookupIfaceTop occ_name
        ; bindIfaceTyVars tv_bndrs $ \ tyvars -> do
 
        { tycon <- fixM ( \ tycon -> do
            { stupid_theta <- tcIfaceCtxt ctxt
-           ; cons  <- tcIfaceDataCons tc_name tycon tyvars rdr_cons
+           ; famInst <- 
+               case mb_family of
+                 Nothing         -> return Nothing
+                 Just (fam, tys) -> 
+                   do { famTyCon <- tcIfaceTyCon fam
+                      ; insttys <- mapM tcIfaceType tys
+                      ; return $ Just (famTyCon, insttys)
+                      }
+           ; cons <- tcIfaceDataCons tc_name tycon tyvars rdr_cons
            ; buildAlgTyCon tc_name tyvars stupid_theta
-                           cons is_rec want_generic gadt_syn
+                           cons is_rec want_generic gadt_syn famInst
            })
         ; traceIf (text "tcIfaceDecl4" <+> ppr tycon)
        ; return (ATyCon tycon)