Fail
public struct Fail<Element, Failure> : AsyncSequence where Failure : Error
extension Fail: AsyncIteratorProtocol
An asynchronous sequence that immediately throws an error when iterated.
Once the error has been thrown, the iterator will return nil to mark the end of the sequence.
let stream = Fail<Int, TestError>(error: TestError())
do {
for try await value in stream {
print(value)
}
} catch {
print("Error!")
}
// Prints:
// Error!
-
Creates an async sequence that throws an error.
Declaration
Swift
public init(error: Failure)
Parameters
error
The error to throw.
-
Creates an async iterator that emits elements of this async sequence.
Declaration
Swift
public func makeAsyncIterator() -> Fail<Element, Failure>
Return Value
An instance that conforms to
AsyncIteratorProtocol
.
-
next()
AsynchronousProduces the next element in the sequence.
Declaration
Swift
public mutating func next() async throws -> Element?
Return Value
The next element or
nil
if the end of the sequence is reached.