{"ast_node_type":"other","tokens":[{"end":100,"kind":"keyword","start":0,"text":"this.ident_and_label_to_local_id.insert(pat_node_id,"}]}
                    this.ident_and_label_to_local_id.insert(pat_node_id, param.pat.hir_id.local_id);
                    // Target expr needs to lower `self` path.
                    this.lower_target_expr(&block)