invokeOnFirst

suspend fun <T, O> Iterable<Deferred<T>>.invokeOnFirst(scope: CoroutineScope, cancelOnResult: Boolean = true, callback: suspend (T) -> O): O(source)
suspend fun <T, O> invokeOnFirst(scope: CoroutineScope, vararg variants: Deferred<T>, cancelOnResult: Boolean = true, callback: suspend (T) -> O): O(source)