JavaScript YUI3 使用全局变量？

Question

我不知道如何从 YUI3 中更新全局变量。

考虑以下代码:

window.myVariable = 'data-one';
var yuiWrap = YUI().use('node',function(Y) {
  console.log(window.myVariable); // 'data-one'
  window.myVariable = 'data-two';
  console.log(window.myVariable); // 'data-two'
});
console.log(window.myVariable); // 'data-one'

谁能给我解释一下？这给我带来了很多麻烦。为什么可以访问 window.myVariable 但不能从 YUI3 block 中正确更新？

我认为这可能与 Closures 有关但我不明白为什么闭包应该应用于全局“窗口”对象。

帮忙吗？

Answer 1

回调不会立即触发，而是在发生某些事情后触发:

Attaches one or more modules to the YUI instance. When this is executed, the requirements are analyzed, and one of several things can happen:

• All requirements are available on the page -- The modules are attached to the instance. If supplied, the use callback is executed synchronously.
• Modules are missing, the Get utility is not available OR the 'bootstrap' config is false -- A warning is issued about the missing modules and all available modules are attached.
• Modules are missing, the Loader is not available but the Get utility is and boostrap is not false -- The loader is bootstrapped before doing the following....
• Modules are missing and the Loader is available -- The loader expands the dependency tree and fetches missing modules. When the loader is finshed the callback supplied to use is executed asynchronously.