[project @ 2000-07-17 11:28:32 by simonpj]

[ghc-hetmet.git] / ghc / compiler / typecheck / Inst.lhs

diff --git a/ghc/compiler/typecheck/Inst.lhs b/ghc/compiler/typecheck/Inst.lhs
index d4d8b48..2311800 100644 (file)
--- a/ghc/compiler/typecheck/Inst.lhs
+++ b/ghc/compiler/typecheck/Inst.lhs
@@ -60,7 +60,7 @@ import Name   ( OccName, Name, mkDictOcc, mkMethodOcc, mkIPOcc,
 import PprType ( pprPred )     
 import Type    ( Type, PredType(..), ThetaType,
                  mkTyVarTy, isTyVarTy, mkDictTy, mkPredTy,
-                 splitForAllTys, splitSigmaTy,
+                 splitForAllTys, splitSigmaTy, funArgTy,
                  splitRhoTy, tyVarsOfType, tyVarsOfTypes, tyVarsOfPred,
                  mkSynTy, tidyOpenType, tidyOpenTypes
                )
@@ -703,14 +703,11 @@ lookupInst inst@(LitInst u (OverloadedFractional f) ty loc)
 
   | otherwise 
   = tcLookupValueByKey fromRationalClassOpKey  `thenNF_Tc` \ from_rational ->
-
-       -- The type Rational isn't wired in so we have to conjure it up
-    tcLookupTyConByKey rationalTyConKey        `thenNF_Tc` \ rational_tycon ->
+    newMethodAtLoc loc from_rational [ty]      `thenNF_Tc` \ (method_inst, method_id) ->
     let
-       rational_ty  = mkSynTy rational_tycon []
+       rational_ty  = funArgTy (idType method_id)
        rational_lit = HsLitOut (HsFrac f) rational_ty
     in
-    newMethodAtLoc loc from_rational [ty]              `thenNF_Tc` \ (method_inst, method_id) ->
     returnNF_Tc (GenInst [method_inst] (HsApp (HsVar method_id) rational_lit))
 
   where