oop - this.field 构造函数参数列表和继承字段的语法糖。

Question

请考虑以下完全可以正常工作的示例:

abstract class Parent {
  String parentField;
}

class Child extends Parent {
  String childField;

  Child(parentField, childField){
    this.parentField = parentField;
    this.childField = childField;
  }
}

当我尝试将子构造函数更改为:

Child(this.parentField, this.childField);

我得到:

error: line X pos Y: unresolved reference to instance field 'parentField' Child(this.parentField, this.childField);

我的问题是:

这是设计决策吗？漏洞？还是缺少值得请求的功能？

Answer 1

这是预期的行为。来自Generative Constructors section of the Dart spec. :

An initializing formal has the form this.id. It is a compile-time error if id is not the name of an instance variable of the immediately enclosing class.