{"ast_node_type":"variable","tokens":[{"end":88,"kind":"keyword","start":0,"text":"let"}]}
        let span = tref.span.shrink_to_lo().to(tref.trait_ref.path.span.shrink_to_lo());
    fn visit_poly_trait_ref(&mut self, tref: &'ast PolyTraitRef) {
        self.with_generic_param_rib(