javascript - 类型错误 : Cannot delete property 'Symbol(@xml.js.parent)' of#

Question

我有这个 Node 类:

export const symbols = {
  parent: Symbol('@xml.js.parent'),
};

export class Node {

  [key: string]: any;

  constructor(parent: Node, name: string) {


    Object.defineProperty(this, symbols.parent, {
      value: parent,
      writable: true,
      enumerable: false
    });

  }

}

我创建了一个新 Node ，然后尝试删除其中一个符号键:

/Users/alexamil/WebstormProjects/oresoftware/xml.json/dist/index.js:141
                    delete self.currentNode[exports.symbols.parent];
                                                            ^

TypeError: Cannot delete property 'Symbol(@xml.js.parent)' of #<Node>
    at ReadStream.<anonymous> (/Users/alexamil/WebstormProjects/oresoftware/xml.json/dist/index.js:141:61)
    at ReadStream.emit (events.js:159:13)
    at addChunk (_stream_readable.js:265:12)
    at readableAddChunk (_stream_readable.js:248:13)
    at ReadStream.Readable.push (_stream_readable.js:209:10)
    at onread (fs.js:2115:12)
    at FSReqWrap.wrapper [as oncomplete] (fs.js:676:17)

被这条线绊倒:

 delete self.currentNode[exports.symbols.parent];

有人知道为什么我无法删除该属性吗？由于将符号属性的 writable 设置为 true 似乎它应该可以工作，但是我不知道。

Answer 1

看起来我需要将 configurable 属性设置为 true

    Object.defineProperty(this, symbols.parent, {
      value: parent,
      writable: true,
      enumerable: false,
      configurable: true
    });