Instance Methodswift 6.1.2_Concurrency

    prefix(while:)

    Returns an asynchronous sequence, containing the initial, consecutive elements of the base sequence that satisfy the given predicate.

    iOS
    13.0+
    macOS
    10.15+
    tvOS
    13.0+
    watchOS
    6.0+
    @preconcurrency func prefix(while predicate: @escaping (Self.Element) async -> Bool) rethrows -> AsyncPrefixWhileSequence<Self>
    Mangled symbol
    sSci12_ConcurrencyE6prefix5whileAA24AsyncPrefixWhileSequenceVyxGSb7ElementQzYac_tKF What are these?
    FNV24 hash
    2XY95

    Parameters

    predicate

    A closure that takes an element as a parameter and returns a Boolean value indicating whether the element should be included in the modified sequence.

    Returns

    An asynchronous sequence of the initial, consecutive elements that satisfy predicate.

    Use prefix(while:) to produce values while elements from the base sequence meet a condition you specify. The modified sequence ends when the predicate closure returns false.

    In this example, an asynchronous sequence called Counter produces Int values from 1 to 10. The prefix(while:) method causes the modified sequence to pass along values so long as they aren’t divisible by 2 and 3. Upon reaching 6, the sequence ends:

    let stream = Counter(howHigh: 10)
    .prefix { $0 % 2 != 0 || $0 % 3 != 0 }
for try await number in stream {
    print(number, terminator: " ")
}
// Prints "1 2 3 4 5 "