Bonsai_extra.One_at_a_timeSourceval effect :
('query -> 'response Bonsai.For_open.Effect.t) Bonsai.For_open.Value.t ->
(('query -> 'response Response.t Bonsai.For_open.Effect.t) * Status.t)
Bonsai.For_open.Computation.tTurns the input effect into an effect which ensures that only one instance of it is running at a time. If another instance of the effect is already running, then Busy is returned instead of running the effect. In addition, this computation also exposes whether or not an instance of the effect is in progress.
CAREFUL: If the effect function raises while it is executing, then the status will stay at busy, since the computation is unable to witness that the effect completed.