{"ast_node_type":"variable","tokens":[{"end":76,"kind":"keyword","start":0,"text":"let"}]}
        let ast_id = db.ast_id_map(source.file_id).ast_id(&macro_call_node);
    for macro_call_node in source_file.syntax().descendants().filter_map(ast::MacroCall::cast) {
        let ast_id = InFile::new(source.file_id, ast_id);