Improve pretty-printing for Insts

compiler/typecheck/Inst.lhs

@@ -94,6 +94,7 @@ import DynFlags
 import Bag
 import Maybes
 import Util
+import Unique
 import Outputable
 import Data.List
 import TypeRep
@@ -602,10 +603,11 @@ pprInst i@(EqInst {tci_left = ty1, tci_right = ty2, tci_co = co})
 	= eitherEqInst i
 		(\covar -> text "Wanted" <+> ppr (TyVarTy covar) <+> dcolon <+> ppr (EqPred ty1 ty2))
 		(\co    -> text "Given"  <+> ppr co              <+> dcolon <+> ppr (EqPred ty1 ty2))
-pprInst inst = ppr (instName inst) <+> dcolon 
+pprInst inst = ppr name <> braces (pprUnique (getUnique name)) <+> dcolon 
 		<+> (braces (ppr (instType inst) <> implicWantedEqs) $$
 		     ifPprDebug implic_stuff)
   where
+    name = instName inst
     (implic_stuff, implicWantedEqs) 
       | isImplicInst inst = (ppr (tci_reft inst),
                             text " &" <+>