{"ast_node_type":"other","tokens":[{"end":66,"kind":"keyword","start":0,"text":".filter_map(|clause|"}]}
                    .filter_map(|clause| clause.as_trait_clause())
                    .map(|(clause, _)| clause.instantiate_supertrait(tcx, trait_ref))
                    .filter(|clause| clause.polarity() == ty::PredicatePolarity::Positive)