javascript - 如何在子构造函数中使用ES6 super调用父方法？

情况：

我正在使用其他属性（时间戳，标识）扩展Node.js（v。8.4.0）错误对象，然后扩展此对象以获得更精细的错误处理。

class MyError extends Error {
  constructor (msg) {
    super(msg);
    this.id = uuid();
    this.timestamp = Date.now();
    // I reckon this can be replaced by this.init(this) ?
    this.name = this.constructor.name;
    Error.captureStackTrace && Error.captureStackTrace(this, this.constructor);
  }

  init (self) {
    self.name = self.constructor.name;
    Error.captureStackTrace && Error.captureStackTrace(self, self.constructor);
  }
}

我希望能够在子错误中不再重复Error.captureStackTrace和this.name调用。因此，我创建了一个在子级中使用的初始化函数，如下所示：

class GranularError extends MyError {
  constructor (msg) {
    super(msg);
    this.type = "error";
    this.status = 500;
    this.code = "internalServerError";
    super.init(this);
  }
}

GranularError然后将再次扩展以获取MoreGranularError等。这就是为什么我想将其保持DRY的原因。

问题：

抛出GranularError或MoreGranularError时，失败并显示

TypeError: (intermediate value).init is not a function

我主要阅读了以下资料，但无法将其应用于问题。任何帮助表示赞赏。

Call parent function which is being overridden by child during constructor chain in JavaScript(ES6)

Parent constructor call overridden functions before all child constructors are finished

http://2ality.com/2015/02/es6-classes-final.html#referring_to_super-properties_in_methods

最佳答案

我不知道您遇到了什么错误，但是没有必要创建init函数。 this.name和Error.captureStack的东西也将在子级中工作，因为this引用了子级实例。

换句话说，您正在尝试解决不存在的问题。

class MyError extends Error {
  constructor (msg) {
    super(msg);
    this.id = Math.random();
    this.timestamp = Date.now();
    this.name = this.constructor.name;
    Error.captureStackTrace && Error.captureStackTrace(this, this.constructor);
  }
}
class GranularError extends MyError {
  constructor (msg) {
    super(msg);
    this.type = "error";
    this.status = 500;
    this.code = "internalServerError";
  }
}

console.dir(new GranularError("this is the error message"));

关于javascript - 如何在子构造函数中使用ES6 super调用父方法？，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/46590566/