private static member in javascript

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原文链接
http://www.litotes.demon.co.uk/js_info/private_static.html
期待简译。

有一些代码，整得有些过了，但还是很值得参考。在jct的代码中看到了类似的用法。
在js中隐藏变量还是有必要的，否则和其他的js库冲突，就会很麻烦，很难找到bug。

贴几段代码，明白人都看得懂。

var MyObject = (function(){
    /*private static (class) member*/
    var counter = 0;
    /*private static method.*/
    function incrementCounter(){
        return counter++;
    };
    /*class constructor.*/
    function constructorFn(id){
        this.id = id;
        var self = this;
        /*call private static (class)
        method and assign the returned
        index to a private instance member.*/
        var index = incrementCounter();
        /*privileged instance method.*/
        this.getIndex = function(){
            return index;
        };
    };
    /*privileged static (class) method
    (a property of the constructor)*/
    constructorFn.getNoOfInsts = function(){
        return counter;
    };
    /*public instance method privaliged at the
    class level*/
    constructorFn.prototype.pubInstMethod = function(){
        ...
    };
    /*return the constructor.*/
    return constructorFn;
})(); //simultaneously define and call (one-off)!

/*public static  member*/
MyObject.pubStatic = "anything"

/*public instance member*/
MyObject.prototype.pubInstVar = 8;

再来一段

var global = this;
(function(){
    var classGroupMember = 3;
    function privateToClassGroup(){
        /*this method could be a utilitiy
        for the classes in the group or used
        as an internal object constructor.*/
        ...
    };
    global.MyObject1 = function(){
        var privteStaticMember = 4;
        function privateStaticMethod(){
            ...
        };
        function constructorFn(id){
            ...
        };
        /*return the constructor.*/
        return constructorFn;
    }();  //simultaneously define and call!
    global.MyObject2 = function(){
        function constructorFn(id){
            ...
        };
        /*return the constructor.*/
        return constructorFn;
    }();  //simultaneously define and call!
    global.MyObject3 = function(){
        function constructorFn(id){
            ...
        };
        /*return the constructor.*/
        return constructorFn;
    }();  //simultaneously define and call!
})();  //simultaneously define and call!

再来一段：

/*constructor function */
function MyObject(){
    ...
}

MyObject.prototype = (function(){
    /*private static (class) member*/
    var privateStaticProp = "anything";
    /*private static method .*/
    function privateStatic Method = function(){
        ...
    }
    return ({
        /*These functions objects are shared by
        all instances that uses this prototype
        and they have access to the private static
        members within the closure that returns
        this object*/
        publicInstanceMethod:function(){
            ...
        },
        setSomething:function(s){
            privateStaticProp = s;
        }
    });
})();

/*public instance member*/
MyObject.prototype.pubInstVar = 8;