{"ast_node_type":"variable","tokens":[{"end":65,"kind":"keyword","start":0,"text":"if"}]}
        if let Some(trait_ref) = poly_trait_ref.no_bound_vars() {
    ) -> Result<(DefId, ty::GenericArgsRef<'tcx>), ErrorGuaranteed> {
            let item_args = self.lowerer().lower_generic_args_of_assoc_item(