X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=ghc%2Fcompiler%2Ftypecheck%2FTcType.lhs;h=8286f64b868f1a444301b113f3da440d519398a4;hb=72c2f581702ca162f56012dd0c8cafcbac284b5c;hp=205292b3227e7df9544b693514af1a8a221ff5f5;hpb=ad552fe28f05107378eec34e13d30b5318339567;p=ghc-hetmet.git

diff --git a/ghc/compiler/typecheck/TcType.lhs b/ghc/compiler/typecheck/TcType.lhs
index 205292b..8286f64 100644
--- a/ghc/compiler/typecheck/TcType.lhs
+++ b/ghc/compiler/typecheck/TcType.lhs
@@ -46,6 +46,7 @@ module TcType (
   isDoubleTy, isFloatTy, isIntTy,
   isIntegerTy, isAddrTy, isBoolTy, isUnitTy, isForeignPtrTy, 
   isTauTy, tcIsTyVarTy, tcIsForAllTy,
+  allDistinctTyVars,
 
   ---------------------------------
   -- Misc type manipulators
@@ -59,7 +60,7 @@ module TcType (
   isPredTy, isClassPred, isTyVarClassPred, predHasFDs,
   mkDictTy, tcSplitPredTy_maybe, predTyUnique,
   isDictTy, tcSplitDFunTy, predTyUnique, 
-  mkClassPred, inheritablePred, isIPPred, mkPredName, 
+  mkClassPred, isInheritablePred, isLinearPred, isIPPred, mkPredName, 
 
   ---------------------------------
   -- Foreign import and export
@@ -74,7 +75,6 @@ module TcType (
   ---------------------------------
   -- Unifier and matcher  
   unifyTysX, unifyTyListsX, unifyExtendTysX,
-  allDistinctTyVars,
   matchTy, matchTys, match,
 
   --------------------------------
@@ -87,7 +87,7 @@ module TcType (
   Type, SourceType(..), PredType, ThetaType, 
   mkForAllTy, mkForAllTys, 
   mkFunTy, mkFunTys, zipFunTys, 
-  mkTyConApp, mkAppTy, mkAppTys, mkSynTy, applyTy, applyTys,
+  mkTyConApp, mkGenTyConApp, mkAppTy, mkAppTys, mkSynTy, applyTy, applyTys,
   mkTyVarTy, mkTyVarTys, mkTyConTy, mkPredTy, mkPredTys, 
 
   isUnLiftedType,	-- Source types are always lifted
@@ -115,7 +115,7 @@ import Type		(	-- Re-exports
 			  unliftedTypeKind, liftedTypeKind, openTypeKind, mkArrowKind, mkArrowKinds,
 			  mkForAllTy, mkForAllTys, defaultKind, isTypeKind, isAnyTypeKind,
 			  mkFunTy, mkFunTys, zipFunTys, 
-			  mkTyConApp, mkAppTy, mkAppTys, mkSynTy, applyTy, applyTys,
+			  mkTyConApp, mkGenTyConApp, mkAppTy, mkAppTys, mkSynTy, applyTy, applyTys,
 			  mkTyVarTy, mkTyVarTys, mkTyConTy, mkPredTy, mkPredTys,
 			  isUnLiftedType, isUnboxedTupleType, isPrimitiveType,
 			  splitNewType_maybe, splitTyConApp_maybe,
@@ -137,7 +137,7 @@ import OccName		( OccName, mkDictOcc )
 import NameSet
 import PrelNames	-- Lots (e.g. in isFFIArgumentTy)
 import TysWiredIn	( ptrTyCon, funPtrTyCon, addrTyCon, unitTyCon )
-import BasicTypes	( ipNameName )
+import BasicTypes	( IPName(..), ipNameName )
 import Unique		( Unique, Uniquable(..) )
 import SrcLoc		( SrcLoc )
 import Util		( cmpList, thenCmp, equalLength )
@@ -250,7 +250,9 @@ isUserTyVar tv = case mutTyVarDetails tv of
 
 isSkolemTyVar :: TcTyVar -> Bool
 isSkolemTyVar tv = case mutTyVarDetails tv of
-		      SigTv -> True
+		      SigTv  -> True
+		      ClsTv  -> True
+		      InstTv -> True
 		      oteher -> False
 
 isHoleTyVar :: TcTyVar -> Bool
@@ -371,11 +373,11 @@ tcSplitTyConApp ty = case tcSplitTyConApp_maybe ty of
 			Nothing	   -> pprPanic "tcSplitTyConApp" (pprType ty)
 
 tcSplitTyConApp_maybe :: Type -> Maybe (TyCon, [Type])
--- Newtypes are opaque, so they may be split
 tcSplitTyConApp_maybe (TyConApp tc tys) 	= Just (tc, tys)
 tcSplitTyConApp_maybe (FunTy arg res)   	= Just (funTyCon, [arg,res])
 tcSplitTyConApp_maybe (NoteTy n ty)     	= tcSplitTyConApp_maybe ty
 tcSplitTyConApp_maybe (SourceTy (NType tc tys)) = Just (tc,tys)
+	-- Newtypes are opaque, so they may be split
 	-- However, predicates are not treated
 	-- as tycon applications by the type checker
 tcSplitTyConApp_maybe other	        	= Nothing
@@ -453,6 +455,31 @@ tcSplitDFunTy ty
     (tvs, theta, clas, tys) }}
 \end{code}
 
+(allDistinctTyVars tys tvs) = True 
+	iff 
+all the types tys are type variables, 
+distinct from each other and from tvs.
+
+This is useful when checking that unification hasn't unified signature
+type variables.  For example, if the type sig is
+	f :: forall a b. a -> b -> b
+we want to check that 'a' and 'b' havn't 
+	(a) been unified with a non-tyvar type
+	(b) been unified with each other (all distinct)
+	(c) been unified with a variable free in the environment
+
+\begin{code}
+allDistinctTyVars :: [Type] -> TyVarSet -> Bool
+
+allDistinctTyVars []       acc
+  = True
+allDistinctTyVars (ty:tys) acc 
+  = case tcGetTyVar_maybe ty of
+	Nothing 		      -> False 	-- (a)
+	Just tv | tv `elemVarSet` acc -> False	-- (b) or (c)
+		| otherwise           -> allDistinctTyVars tys (acc `extendVarSet` tv)
+\end{code}    
+
 
 %************************************************************************
 %*									*
@@ -530,7 +557,7 @@ isIPPred :: SourceType -> Bool
 isIPPred (IParam _ _) = True
 isIPPred other	      = False
 
-inheritablePred :: PredType -> Bool
+isInheritablePred :: PredType -> Bool
 -- Can be inherited by a context.  For example, consider
 --	f x = let g y = (?v, y+x)
 --	      in (g 3 with ?v = 8, 
@@ -539,8 +566,12 @@ inheritablePred :: PredType -> Bool
 --	g :: (?v :: a) => a -> a
 -- but it doesn't need to be quantified over the Num a dictionary
 -- which can be free in g's rhs, and shared by both calls to g
-inheritablePred (ClassP _ _) = True
-inheritablePred other	     = False
+isInheritablePred (ClassP _ _) = True
+isInheritablePred other	     = False
+
+isLinearPred :: TcPredType -> Bool
+isLinearPred (IParam (Linear n) _) = True
+isLinearPred other		   = False
 \end{code}
 
 
@@ -882,38 +913,6 @@ boxedMarshalableTyCon tc
 %*									*
 %************************************************************************
 
-(allDistinctTyVars tys tvs) = True 
-	iff 
-all the types tys are type variables, 
-distinct from each other and from tvs.
-
-This is useful when checking that unification hasn't unified signature
-type variables.  For example, if the type sig is
-	f :: forall a b. a -> b -> b
-we want to check that 'a' and 'b' havn't 
-	(a) been unified with a non-tyvar type
-	(b) been unified with each other (all distinct)
-	(c) been unified with a variable free in the environment
-
-\begin{code}
-allDistinctTyVars :: [Type] -> TyVarSet -> Bool
-
-allDistinctTyVars []       acc
-  = True
-allDistinctTyVars (ty:tys) acc 
-  = case tcGetTyVar_maybe ty of
-	Nothing 		      -> False 	-- (a)
-	Just tv | tv `elemVarSet` acc -> False	-- (b) or (c)
-		| otherwise           -> allDistinctTyVars tys (acc `extendVarSet` tv)
-\end{code}    
-
-
-%************************************************************************
-%*									*
-\subsection{Unification with an explicit substitution}
-%*									*
-%************************************************************************
-
 Unify types with an explicit substitution and no monad.
 Ignore usage annotations.