+
+import CmdLineOpts ( opt_FoldrBuildOn )
+import CoreUtils ( coreExprType, mkCoreIfThenElse )
+import PrelInfo ( nilDataCon, consDataCon, listTyCon,
+ mkBuild, foldrId )
+import Type ( mkTyVarTy, mkForAllTy, mkFunTys )
+import TysPrim ( alphaTy )
+import TyVar ( alphaTyVar )