{"ast_node_type":"other","tokens":[{"end":89,"kind":"keyword","start":0,"text":"if"}]}
                            if const_stab.is_const_stable() != stable_or_implied_stable {
                            // the const stability of a trait impl must match the const stability on the trait.
                                let trait_span = self.tcx.def_ident_span(trait_id).unwrap();