{"ast_node_type":"other","tokens":[{"end":63,"kind":"keyword","start":0,"text":"self.report_placeholder_type_error(vec![span],"}]}
        self.report_placeholder_type_error(vec![span], vec![]);
    fn ct_infer(&self, _: Option<&ty::GenericParamDef>, span: Span) -> Const<'tcx> {
        ty::Const::new_error_with_message(self.tcx(), span, "bad placeholder constant")