ydb/yql/essentials/tests/s-expressions/suites/InMem/Seq.yqls

(
(let config (DataSource 'config))

(let res_sink (DataSink 'result))

(let v1 (String 'test1))
(let q1 (QueueCreate (TypeOf v1) (Uint64 '1) (Uint64 '1) (DependsOn v1)))
(let new_q1 (QueuePush (QueuePop q1) v1))
(let q1_item (QueuePeek q1 (Uint64 '0) (DependsOn v1)))
(let new_q1_item (QueuePeek new_q1 (Uint64 '0) (DependsOn v1)))

# will be (test1, test1)
(let result '(new_q1_item q1_item))
(let world (Write! world res_sink (Key) result '('('type))))


(let v2 (String 'test2))
(let q2 (QueueCreate (TypeOf v2) (Uint64 '1) (Uint64 '1) (DependsOn v2)))
(let new_q2 (QueuePush (QueuePop q2) v2))
(let q2_item (QueuePeek q2 (Uint64 '0) (DependsOn v2)))
(let new_q2_item (QueuePeek new_q2 (Uint64 '0) (DependsOn v2)))

# enforce q2_item to be calculated first
(let result '((Seq q2_item new_q2_item) q2_item))
(let world (Write! world res_sink (Key) result '('('type))))


(let world (Commit! world res_sink))
(return world)
)