Javascript中的闭包

http://jibbering.com/faq/notes/closures/

原文较多，这里摘一些比较重要的来说明问题。

The simple explanation of a Closure is that ECMAScript allows inner functions; function definitions and function expressions that are inside the function bodes of other functions.

最简单的定义：一个内部函数（这个就不用再解释了吧。。），感觉和java的内部类有点相似。。

所以

those inner functions are allowed access to all of the local variables, parameters and declared inner functions within their outer function(s).

内部函数可以访问外部所有的变量、其他内部函数等所有东西。。

只是这样还不够，还要再满足一个条件才能形成闭包。

A closure is formed when one of those inner functions is made accessible outside of the function in which it was contained

即当这个内部函数在包含它的外部函数之外被调用时，就形成了闭包。