协议内的Typealias

Question

我的协议中有一个typealias。我必须将typealias添加到符合类型还是有其他选择？我的目标是声明一次typealias。

protocol SomeProtocol { 
    associatedtype T 
    typealias Closure = (T) -> Void 
    var blocks: [Closure] { get set } 
} 

struct SomeStruct<T>: SomeProtocol { 
    typealias Closure = (T) -> Void // <- do I have to add this? 
    var blocks: [Closure] 
} 

仅供参考。我只是寻找一个更简单的实现的typealias。

Answer 1

你不一定需要在struct的typealias - 它可以推断出：

protocol SomeProtocol { 
    associatedtype T 
    typealias Closure = (T) -> Void 
    var blocks: [Closure] { get set } 
} 

struct SomeStruct<T>: SomeProtocol { 
    var blocks: [(T) -> Void] 
} 

let someStruct = SomeStruct<Int>(blocks: [{someInt in print(someInt)}]) 
someStruct.blocks[0](123)