如果 IIFE 只包含一个立即导出到全局作用域的变量声明，为什么还要费心呢？
现在已经是晚上了，所以我的功能可能不太好，但我找到了这段代码，我似乎无法弄清楚为什么它是这样使用的（注意：我明白它的作用，我不明白的是它背后的含义）。
(function() {
var narcissus = {
options: {
version: 185,
},
hostGlobal: this
};
Narcissus = narcissus;
})();
自执行的匿名函数用于避免全局命名空间的污染，但是此代码不需要引入除 Narcissus 之外的其他变量，因此它可以很容易地重写为 Narcissus = { ...};。我能想到的一些可能的原因是代码的面向未来或实现缺陷。有什么我看不到的吗？
It's late in the evening here so I may not be functioning very well, but I found this piece of code and I can't seem to figure out why it's used like this (NOTE: I understand what it does, what I don't understand is the meaning behind it).
(function() {
var narcissus = {
options: {
version: 185,
},
hostGlobal: this
};
Narcissus = narcissus;
})();
Self-executing anonymous functions are used to avoid pollution of the global namespace, but this code doesn't need to introduce other variables than Narcissus so it could have very easily be rewritten as Narcissus = {...};. Some possible reasons I can think of are future-proofing of the code or implementation flaw. Is there something I fail to see?
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从可维护性的角度来看，它允许作者稍后在闭包范围中添加代码，这些代码不会在
narcissus的创建和Narcissus的分配之间泄漏。尽管在本例中没有任何代码，所以除了上面提到的this内容之外，我没有看到任何收益。From a maintainability standpoint it allows the author to later add code in a Closure scope that doesn't get leaked between the creation of
narcissusand the assignment ofNarcissus. Though in this case there isn't any code there so I don't see any gains other than thethisstuff mentioned above.您缺少的部分是 javascript 是一种区分大小写的语言，因此
他通过省略
var关键字将Narcissus添加到全局范围，或者 Narcissus 已经在全局范围内可用，或Narcissus已在调用此函数的范围内定义。然后将其定义为匿名函数内的对象 narcissus 。
我无法告诉你他为什么这样做，但看起来他可能已经在
this引用一个对象的范围内，并且他想设置键hostGlobal到全局对象而不是当前范围的对象。这就是为什么他将其作为匿名函数运行，因为它们是在全局范围而不是函数范围中执行的。所以在他的代码中
hostGlobal: this指的是全局对象。当然，他可以只使用
hostGlobal: window，除非此代码也在非浏览器环境中运行，例如 node.js，其中全局对象是global而不是窗口。所以他可能会用一种非常不直观的方法来实现这一目标。希望这有帮助
The part your missing is that javascript is a case sensitive language so
He is adding
Narcissusto the global scope by omitting thevarkeyword, or Narcissus is already available in the global scope, orNarcissushas already defined in the scope of where this function is being called.Then defining it as the object
narcissusinside the anonymous function.I cannot tell you why he is doing this, but it seems like he might already be inside a scope where
thisis referring to an object, and he want to set the keyhostGlobalto the global object not the currently scoped object.That is why he is running it as an anonymous function, as they are executed in the global scope not function scope. So in his code
hostGlobal: thisis referring to the global object.Of course he could just use
hostGlobal: window, unless this code is also being run in non browser environments such as node.js where the global object isglobalnotwindow. So he might be doing it as a very unintuitive method of achieving.Hope this helps