泛型 – 如何在Swift中使用泛型继承另一个类？

protocol Named{
  var firstName:String {get set}
  var lastName: String {get set}

  var fullName: String{ get }

  }

class Person: Named{

  var firstName: String
  var lastName: String

  var fullName: String{
  return "(firstName) (lastName)"
  }

  init(firstName: String,lastName: String){
    self.firstName = firstName
    self.lastName = lastName
  }

}

class A<T: Named>{
  var named: T

  init(named: T){
    self.named = named
  }
}




class B<M: Named>: A<M>{

  init(){
    let person = Person(firstName: "John",lastName: "Appleseed")
    person.fullName
    super.init(named: person as M)
  }

}



let b = B<Person>()

b.named.fullName

请注意,当您从泛型类继承时,您必须将子类作为泛型,并且超类必须传递子类中使用的相同泛型变量.它似乎也需要显式类型转换来表示泛型(在我们的例子中是协议),请参阅类B中的初始化程序.初始化子类还需要在初始化为B()时传递显式泛型类型.这是我自己的实验.可以有简单而简洁的方法来做到这一点.