Javascript 时间死区 [英] Javascript Temporal Dead Zone

问题描述

我真的不明白下面的代码片段发生了什么.

I don't really understand what's happening with the snippet below.

我预计会因为 Temporal Dead Zone 而出现错误，但看起来 const baz = '123123'; 被提升了.

I would expect an error because of the Temporal Dead Zone, but it looks like const baz = '123123'; gets hoisted.

一切正常的原因是什么?

What's the reason why everything works?

class Foo {
  constructor() { 
    console.log('Foo baz is:', baz) 
  }
}

function log() {
  console.log('log baz is:', baz);
}

const baz = '123123';

log();
new Foo();

推荐答案

不需要吊起来.

函数在被调用之前不会尝试访问变量.

The functions don't try to access the variable until they are called.

在定义常量并为其分配值之前不要调用它们.

You don't call them until after the constant is defined and has a value assigned to it.

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