fn visit_waiters<F>(
query_map: &QueryMap,
query: QueryJobId,
visit: F,
) -> Option<Option<(QueryJobId, usize)>>
Expand description
Visits all the non-resumable and resumable waiters of a query.
Only waiters in a query are visited.
visit
is called for every waiter and is passed a query waiting on query_ref
and a span indicating the reason the query waited on query_ref
.
If visit
returns Some, this function returns.
For visits of non-resumable waiters it returns the return value of visit
.
For visits of resumable waiters it returns Some(Some(Waiter)) which has the
required information to resume the waiter.
If all visit
calls returns None, this function also returns None.