X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=compiler%2Ftypes%2FFamInstEnv.lhs;h=b9276b7cf6ee2ff406969c808deff9ae11ff7a8d;hb=272fb49ecfeffe7aaa66b9b61bab12d8a858458d;hp=9b49f5c34393fb9ac329bd4620894c90678cd6be;hpb=8a5d47de2b82d9cca86546a7bd89d915488934ef;p=ghc-hetmet.git

diff --git a/compiler/types/FamInstEnv.lhs b/compiler/types/FamInstEnv.lhs
index 9b49f5c..b9276b7 100644
--- a/compiler/types/FamInstEnv.lhs
+++ b/compiler/types/FamInstEnv.lhs
@@ -6,10 +6,12 @@ FamInstEnv: Type checked family instance declarations
 
 \begin{code}
 module FamInstEnv (
-	FamInst(..), famInstTyCon, pprFamInst, pprFamInstHdr, pprFamInsts, 
+	FamInst(..), famInstTyCon, famInstTyVars, 
+	pprFamInst, pprFamInstHdr, pprFamInsts, 
 	famInstHead, mkLocalFamInst, mkImportedFamInst,
 
-	FamInstEnv, emptyFamInstEnv, extendFamInstEnv, extendFamInstEnvList, 
+	FamInstEnvs, FamInstEnv, emptyFamInstEnv, 
+	extendFamInstEnv, extendFamInstEnvList, 
 	famInstEnvElts, familyInstances,
 
 	lookupFamInstEnv, lookupFamInstEnvUnify
@@ -32,7 +34,6 @@ import UniqFM
 import Outputable
 
 import Maybe
-import Monad
 \end{code}
 
 
@@ -60,6 +61,8 @@ data FamInst
 --
 famInstTyCon :: FamInst -> TyCon
 famInstTyCon = fi_tycon
+
+famInstTyVars = fi_tvs
 \end{code}
 
 \begin{code}
@@ -140,6 +143,9 @@ InstEnv maps a family name to the list of known instances for that family.
 \begin{code}
 type FamInstEnv = UniqFM FamilyInstEnv	-- Maps a family to its instances
 
+type FamInstEnvs = (FamInstEnv, FamInstEnv)
+ 	-- External package inst-env, Home-package inst-env
+
 data FamilyInstEnv
   = FamIE [FamInst]	-- The instances for a particular family, in any order
   	  Bool 		-- True <=> there is an instance of form T a b c
@@ -174,7 +180,7 @@ extendFamInstEnv inst_env ins_item@(FamInst {fi_fam = cls_nm, fi_tcs = mb_tcs})
     add (FamIE items tyvar) _ = FamIE (ins_item:items)
 				      (ins_tyvar || tyvar)
     ins_tyvar = not (any isJust mb_tcs)
-\end{code}		      
+\end{code}
 
 %************************************************************************
 %*									*
@@ -188,8 +194,7 @@ families), and then, it doesn't matter which match we choose (as the
 instances are guaranteed confluent).
 
 \begin{code}
-lookupFamInstEnv :: (FamInstEnv 	-- External package inst-env
-		    ,FamInstEnv) 	-- Home-package inst-env
+lookupFamInstEnv :: FamInstEnvs
 	         -> TyCon -> [Type]		-- What we are looking for
 	         -> [(TvSubst, FamInst)] 	-- Successful matches
 lookupFamInstEnv (pkg_ie, home_ie) fam tys