// 观察者模式
var observer = {

    addSubscriber: function (callback) {
        this.subscribers[this.subscribers.length] = callback;
    },

    removeSubscriber: function (callback) {
        var len = this.subscribers.length,
            i;
        for (i = 0; i < len - 1; i++) {
            if (this.subscribers[i] === callback) {
                this.subscribers.splice(i, 1);
            }
        }
    },

    publish: function (what) {
        var len = this.subscribers.length,
            i;
        for (i = 0; i < len; i++) {
            if (typeof this.subscribers[i] === "function") {
                this.subscribers[i](what);
            }
        }
    },

    make: function (o) {
        var i;
        for (i in this) {
            o[i] = this[i];
            
        }
        o.subscribers = [];
        console.warn('发布者注册完毕')
    }

};

// 注册发布者
var tonightPaper = {
    newIssue: function () {
        var paper = "Have a wonderful love !";
        this.publish(paper);
    }
};

observer.make(tonightPaper);


// 注册订阅者

var glue = {
    read: function (what) {
        console.warn("It says" + what);
    }
};

tonightPaper.addSubscriber(glue.read);
tonightPaper.newIssue();