有“自我”吗？输入代表当前类型的scala？ [英] Is there a "SELF" type in scala that represents the current type?

问题描述

我正在学习Scala并且有一些我无法找到关于语言的事情：

I'm learning Scala and there is a thing that I can't find out about the language:

前段时间我在Lisaac编程非常舒服，在Lisaac中，我可以写一个 PERSON 的类，其中有一个插槽列表：ARRAY [SELF] ，相当于有 list：ARRAY [PERSON] ，因为 SELF 是该广告位所在的对象的类型。

Some time ago I was very comfortable programming in Lisaac, and in Lisaac I could write a class PERSON with a slot list:ARRAY[SELF], which was equivalent to have list:ARRAY[PERSON], since SELF is the type of the object where that slot is.

但是通过使用 SELF ，如果我写第二个班级 STUDENT 那个继承自 PERSON ，然后 STUDENT 将继承该插槽更改 SELF 对于学生，所以学生将有一个学生而不是 PERSON 。

But by using SELF, if I write a second class STUDENT that inherits from PERSON, then STUDENT would inherit that slot changing SELF for STUDENT, so STUDENT would have a list of STUDENT instead of PERSON.

可以在Scala中完成吗？我无法找到任何相关内容。

Can that be done in Scala? I can´t find out anything about that.

谢谢！

推荐答案

<我不确定这对你是否真的有用，但我能想到的最接近的是 this.type 。例如：

scala> class A { val l: List[this.type] = Nil }  
defined class A

scala> new A().l
res3: List[A] = List()

scala> class B extends A
defined class B

scala> new B().l
res4: List[B] = List()

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