这是我的代码:
class Main {
init() {
let x = Sub(s: foo)
}
func foo(completion: @escaping (String?)->Void) {
DispatchQueue.global().async {
completion(nil)
}
}
}
class Sub {
var s: ((String?)->Void)->Void
init(s: @escaping ((String?)-&g
假设我有两个功能:
functionA(@escaping closureA: ((Double) -> ())) {
// Some Code for function A
}
functionB(@escaping closureB: ((Double) -> ())) {
// Some Code for function B
}
如果我想从函数A调用functionB,如何将函数A的闭包参数作为参数传递给函数B的参数?
像这样的东西:
func A(@escaping closureA: ((Double) -> ())) {
// Some
我有以下代码:
typealias queryCompletionBlock = (_ finished:Bool) -> Void
func queryForParams(@escaping completion:queryCompletionBlock)
但是我得到了一个错误
Attribute can only be applied to types, not declarations
问题是函数要求块转义。如何使用转义块声明上面的函数?
我正在尝试用Swift 3实现一个由启发的小型未来库,这里是我的实现:
public enum Result<T, E: Error> {
case Success(T)
case Error(E)
}
public struct Future<T, E: Error> {
public typealias ResultType = Result<T, E>
public typealias Completion = (ResultType) -> Void
public typealias AsyncOper
我有一个函数定义了这样的闭包:
func synchronizeData(completion externalCompletion: RequestsCompletionHandler?) {
let closure = {
(operationCompletion:@escaping ()->Void) in
assert(Thread.isMainThread, "must be the main thread")
/*
Internal (non-optional) completi