jQuery memory&unique&stopOnfalse

memory：保持以前的值，将添加到这个列表的后面的最新的值立即执行调用任何回调 (像一个递延 Deferred)。

回调函数是从异步队列Deferred分离出来的，所以很多的接口设计都是为了契合Deferred接口，memory用的很多，这个缓存的设计这里提及一下

主要是用来实现deferred的异步收集与pipe管道风格的数据传递的，具体在Deferred有详解，这里大概了解下作用范围。

memory这个有点不好理解，我们还是通过列子说明下，看下面的代码：

function fn1(val) {
        console.log('fn1 says:' + val);
    }

    function fn2(val) {
        console.log('fn2 says ' + val);
    }
    function fn3(val){
        console.log("fn3 says " + val);
    }

     /* var cbs = $.Callbacks("memory");
    cbs.add(fn1);
    cbs.fire('foo');
    console.log('..........');
    cbs.add(fn2);
    cbs.fire('bar');
    console.log('..........');
    cbs.add(fn3);
    cbs.fire('aaron');*/
    function callbacks(options){
        var list = [];
        var self;
        var memory;
        var firingStart;
        function _fire(data){
            memory = options === 'memory' && data;//===>&&>=
            firingIndex = firingStart || 0;
            firingStart = 0;//改变firingStart，之后的fire还是从0开始。
            firingLength = list.length;
            for(; list && firingIndex < firingLength; firingIndex++){
                list[firingIndex](data);
            }
        };
        self = {
            add: function(fn){
                var start = list.length;
                list.push(fn);
                if(memory){
                    firingStart = start;//改变firingStart
                    _fire(memory);
                }
            },
            fire: function(args){
                if(list){
                    _fire(args);
                    if(options === "once"){
                        list = undefined;
                    }
                }
            }
        };
        return self;
    }
    var cc = callbacks("memory");
    cc.add(fn1);
    cc.fire("111");
    console.log("...............");
    cc.add(fn2);
    cc.fire("222");

 unique:

function fn1(val) {
        console.log('fn1 says:' + val);
    }
    function fn2(val) {
        console.log('fn2 says ' + val);
    }
    function fn3(val){
        console.log("fn3 says " + val);
    }

      /*var cbs = $.Callbacks("unique");
    cbs.add(fn1);
    cbs.add(fn1);
    cbs.add(fn1);
    cbs.fire('foo');
    console.log('..........');*/

    /*cbs.add(fn2);
    cbs.fire('bar');
    console.log('..........');
    cbs.add(fn3);
    cbs.fire('aaron');*/
    function callbacks(options){
        var list = [];
        var self;
        var memory;
        var firingStart;
        function _fire(data){
            memory = options === 'memory' && data;//===>&&>=
            firingIndex = firingStart || 0;
            firingStart = 0;//改变firingStart，之后的fire还是从0开始。
            firingLength = list.length;
            for(; list && firingIndex < firingLength; firingIndex++){
                list[firingIndex](data);
            }
        };
        self = {
            add: function(fn){
                var start = list.length;
                if(options === "unique"){
                    if(list.indexOf(fn) === -1){
                        list.push(fn);
                    }
                }else{
                    list.push(fn);
                }

                if(memory){
                    firingStart = start;//改变firingStart
                    _fire(memory);
                }
            },
            fire: function(args){
                if(list){
                    _fire(args);
                    if(options === "once"){
                        list = undefined;
                    }
                }
            }
        };
        return self;
    }
    var cc = callbacks("unique");
    cc.add(fn1);
    cc.add(fn1);
    cc.add(fn1);
    cc.fire("111");

 stopOnfalse：

function fn1(val) {
        console.log('fn1 says:' + val);
        return false;
    }
    function fn2(val) {
        console.log('fn2 says ' + val);
        return false;
    }
    function fn3(val){
        console.log("fn3 says " + val);
    }

      /*var cbs = $.Callbacks("stopOnFalse");
    cbs.add(fn1);
    cbs.fire('foo');
    console.log('..........');
    cbs.add(fn2);
    cbs.fire('bar');
    console.log('..........');
    cbs.add(fn3);
    cbs.fire('aaron');*/
    /*cbs.add(fn2);
    cbs.fire('bar');
    console.log('..........');
    ;*/
    function callbacks(options){
        var list = [];
        var self;
        var memory;
        var firingStart;
        function _fire(data){
            memory = options === 'memory' && data;//===>&&>=
            firingIndex = firingStart || 0;
            firingStart = 0;//改变firingStart，之后的fire还是从0开始。
            firingLength = list.length;
            for(; list && firingIndex < firingLength; firingIndex++){
               if(list[firingIndex](data) === false && options === 'stopOnFalse'){
                   break;
               };
            }
        };
        self = {
            add: function(fn){
                var start = list.length;
                if(options === "unique"){
                    if(list.indexOf(fn) === -1){
                        list.push(fn);
                    }
                }else{
                    list.push(fn);
                }

                if(memory){
                    firingStart = start;//改变firingStart
                    _fire(memory);
                }
            },
            fire: function(args){
                if(list){
                    _fire(args);
                    if(options === "once"){
                        list = undefined;
                    }
                }
            }
        };
        return self;
    }
    var cc = callbacks("stopOnFalse");
    cc.add(fn1);
    cc.fire("111");
    cc.add(fn2);
    cc.fire("222");