{"ast_node_type":"other","tokens":[{"end":89,"kind":"keyword","start":0,"text":"(tt::TopSubtree::empty(tt::DelimSpan"}]}
                (tt::TopSubtree::empty(tt::DelimSpan { open: span, close: span }), None),
            Some(_) => ExpandResult::new(
                ExpandError::new(span, ExpandErrorKind::MacroDefinition),