绑定函数为null [英] Binding function to null

问题描述

function f() {
  return this.x
}
f = f.bind(null)
f() // undefined
x = 1
f() // 1

我找不到任何页面它表示绑定到 null 或 undefined 无效。在任何地方写入这个成为 bind 的第一个参数的链接，未提及异常。有人可以提供某个描述此类行为的链接吗？

I cannot find any page where it says that binding to null or undefined has no effect. Everywhere it is written that this becomes a link to the first argument of bind, exceptions are not mentioned. Can somebody provide a link to somewhere describing such behaviour?

推荐答案

链接到段落，其中指定了此效果。问题是，falsey 这个被全局对象替换而不是绑定，但是在绑定函数调用时。

Link to the paragraph, where this effect is specified. The problem was, falsey this is replaced with global object not while binding, but at the moment of bound function call.

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