swift Swift中协议和扩展的各种用途

Posted 2021-05-19

protocol ExampleProtocol {
    associatedtype AType
    func example(toString: AType)
}

class Example: ExampleProtocol {
    
}

class ExampleOverride: ExampleProtocol  {
    typealias AType = String
}

extension ExampleProtocol {
    func example(toString: String) {
        print("\(toString) From Base Example Protocol")
    }
}

extension ExampleProtocol where Self: ExampleOverride {
    func example(toString: String) {
        print("\(toString) From Overriding Example Protocol Extension")
    }
}

let example = Example()
let exampleOverride = ExampleOverride()

example.example(toString: "Test")           //Test From Base Example Protocol
exampleOverride.example(toString: "Test")   //Test From Overriding Example Protocol Extension