做__proto__和Object.getPrototype公开的功能完全相同？ [英] Do __proto__ and Object.getPrototype of expose exactly the same functionality?

问题描述

ES2015中 __ proto __ 的标准化否定了对 Object.getPrototypeOf 的需要？

Does the standardization of __proto__ in ES2015 negate the need for Object.getPrototypeOf?

推荐答案

执行 __ proto __ 和 Object。 getPrototype 显示完全相同的功能？

Do __proto__ and Object.getPrototype of expose exactly the same functionality?

否。 .__ proto __ 仅适用于继承自 Object.prototype 的对象。而 Object.getPrototype 不允许变形原型。

No. .__proto__ only works on objects that inherit from Object.prototype. And Object.getPrototype doesn't allow to mutate the prototype.

ES2015中 __ proto __ 的标准化否定了对 Object.getPrototypeOf 的需要。

Does the standardization of __proto__ in ES2015 negate the need for Object.getPrototypeOf?

你倒退了ES5 Object.getPrototypeOf 和ES6 Object.setPrototypeOf 完全不需要使用 __ proto __ 。

You've got it backwards. ES5 Object.getPrototypeOf and ES6 Object.setPrototypeOf completely negate the need to ever use __proto__.

Object.prototype .__ proto __ accessor属性仅在ES6中进行标准化需要它的实现之间的兼容性和互操作性。它被明确地标记为网络传统功能。检查附件B中的注释（ [...] ... [...] [...] [...] [...] [...] [...]程序员在编写新的ECMAScript代码时不应该使用或假设存在[他们]，不鼓励ECMAScript实现实现这些功能）

The Object.prototype.__proto__ accessor property is only standardised in ES6 for backwards compatibility and interoperability between implementations that need it. It's explictly marked as a web legacy feature. Check the note on Annex B ("…legacy features [for] web browser based ECMAScript implementations. [They] have […] undesirable characteristics and […] would be removed from this specification [if not used] by large numbers of existing web pages […]. Programmers should not use or assume the existence of [them] when writing new ECMAScript code. ECMAScript implementations are discouraged from implementing these features.")

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