+lookupGreRn :: RdrName -> RnM GlobalRdrElt
+-- If not found, add error message, and return a fake GRE
+lookupGreRn rdr_name
+ = do { mb_gre <- lookupGreRn_maybe rdr_name
+ ; case mb_gre of {
+ Just gre -> return gre ;
+ Nothing -> do
+ { name <- unboundName rdr_name
+ ; return (GRE { gre_name = name, gre_par = NoParent,
+ gre_prov = LocalDef }) }}}
+