Instance Method
sequencedFlatMapEach(_:)
A variant form of
flatMapEach(on:_:) which guarantees:func sequencedFlatMapEach<Result>(_ transform: @escaping (Value.Element) -> EventLoopFuture<Result>) -> EventLoopFuture<[Result]>Discussion
Explicitly sequential execution of each future returned by the mapping closure; the next future does not being executing until the previous one has yielded a success result.
No further futures will be even partially executed if any one future returns a failure result.
Neither of these are provided by the original version of the method.
See Also
EventLoopFuture
class EventLoopFutureQueueAllows you to queue closures that produce anEventLoopFuture, so each future only gets run if the previous ones complete, succeed, or fail.func mapEach<Result>(KeyPath<Value.Element, Result>) -> EventLoopFuture<[Result]>Gets the value of a key path for each element in the sequence that is wrapped by anEventLoopFuture.func mapEach<Result>((Value.Element) -> Result) -> EventLoopFuture<[Result]>Calls a closure on each element in the sequence that is wrapped by anEventLoopFuture.func mapEachCompact<Result>(KeyPath<Value.Element, Result?>) -> EventLoopFuture<[Result]>Gets the optional value of a key path for each element in the sequence that is wrapped by anEventLoopFuture.func mapEachCompact<Result>((Value.Element) -> Result?) -> EventLoopFuture<[Result]>Calls a closure, which returns anOptional, on each element in the sequence that is wrapped by anEventLoopFuture.func mapEachFlat<ResultSegment>(KeyPath<Value.Element, ResultSegment>) -> EventLoopFuture<[ResultSegment.Element]>Gets the collection value of a key path for each element in the sequence that is wrapped by anEventLoopFuture, combining the results into a single result collection.func mapEachFlat<ResultSegment>((Value.Element) -> ResultSegment) -> EventLoopFuture<[ResultSegment.Element]>Calls a closure which returns a collection on each element in the sequence that is wrapped by anEventLoopFuture, combining the results into a single result collection.func flatMapEach(on: any EventLoop, (Value.Element) -> EventLoopFuture<Void>) -> EventLoopFuture<Void>Calls a closure, which returns anEventLoopFuture, on each element in a sequence that is wrapped by anEventLoopFuture. No results from each future are expected.func flatMapEach<Result>(on: any EventLoop, (Value.Element) -> EventLoopFuture<Result>) -> EventLoopFuture<[Result]>Calls a closure, which returns anEventLoopFuture, on each element in a sequence that is wrapped by anEventLoopFuture.func flatMapEachCompact<Result>(on: any EventLoop, (Value.Element) -> EventLoopFuture<Result?>) -> EventLoopFuture<[Result]>Calls a closure, which returns anEventLoopFuture<Optional>, on each element in a sequence that is wrapped by anEventLoopFuture.func flatMapEachThrowing<Result>((Value.Element) throws -> Result) -> EventLoopFuture<[Result]>Calls a closure on each element in the sequence that is wrapped by anEventLoopFuture.func flatMapEachCompactThrowing<Result>((Value.Element) throws -> Result?) -> EventLoopFuture<[Result]>Calls a closure, which returns anOptional, on each element in the sequence that is wrapped by anEventLoopFuture.func sequencedFlatMapEach((Value.Element) -> EventLoopFuture<Void>) -> EventLoopFuture<Void>An overload ofsequencedFlatMapEach(_:)which returns aVoidfuture instead of[Void]when the result type of the transform closure isVoid.func sequencedFlatMapEachCompact<Result>((Value.Element) -> EventLoopFuture<Result?>) -> EventLoopFuture<[Result]>Variant ofsequencedFlatMapEach(_:)which providescompactMap()semantics by allowing result values to benil. Such results are not included in the output array.static func whenTheySucceed<A, B>(EventLoopFuture<A>, EventLoopFuture<B>, file: StaticString, line: UInt) -> EventLoopFuture<(A, B)>Returns a newEventLoopFuturethat succeeds only if all of the provided fs succeed. The newEventLoopFuturewill contain all of the values fulfilled by the fs.