ydb/yql/essentials/tests/s-expressions/suites/ImplictCasts/Substring.yql

(
(let config (DataSource 'config))
(let world (Configure! world config 'PureDataSource 'yt))

(let res_sink (DataSink 'result))
(let data (Substring (String 'abcde) (Int64 '2) (Uint64 '1)))
(let world (Write! world res_sink (Key) data '('('type))))
(let world (Commit! world res_sink))
(return world)
)