{"ast_node_type":"variable","tokens":[{"end":119,"kind":"keyword","start":0,"text":"let"}]}
        let end_entry = self.spans[start_entry..].partition_point(|&(it, _)| it <= end); // FIXME: this might be wrong?
        let start_entry = self.spans.partition_point(|&(it, _)| it <= start);
        self.spans[start_entry..][..end_entry].iter().map(|&(_, s)| s)