javascript - 为什么标签可以应用于所有语言语句？

Question

According to the ECMAScript standard , 标签可以应用于所有语句。

这意味着以下行是有效的:

myLabel: throw 'whatever'

还有

function foo() {
  myLabel: return 'whatever'
}

console.log(foo())

但这些标签似乎无法使用，这就引出了一个问题:为什么允许使用它们？ (或者我有根本性的误解)

Answer 1

According to Brendan Eich, the author of JavaScript ，这种做法模仿了Java(1996年的新热)，避免了“死标签分析”的需要:

Same as Java, IIRC. We didn't want to require engines to do dead label analysis. I know for sure I didn't want to when I first implemented in SpiderMonkey. This has led to unintended transposed javascript: labels (used to be URL schemes), but they're harmless.