{"ast_node_type":"variable","tokens":[{"end":66,"kind":"keyword","start":0,"text":"let"}]}
                let root = db.parse_or_expand(syntax_ptr.file_id);
            if let Some(syntax_ptr) = body_source_map.self_param_syntax() {
                let node = syntax_ptr.map(|ptr| ptr.to_node(&root).syntax().clone());