函数化1

var mammal = function(spec) {
        var that = {};

        that.saying = function() {
            return spec.saying;
        };

        that.get_name = function() {
            return spec.name;
        };

        that.says = function() {
            return this.saying();
        };

        return that;
    };

var myMammal = mammal({
    name: 'Herb',
    saying: 'Hello world!!!'
});

console.log(myMammal.says());

DC大牛果然对javascript的理解非常透彻，javascript语言精粹真的物超所值，虽然此书很薄。

var mammal = function(spec) {
        var that = {};

        that.get_name = function() {
            return spec.name;
        };

        that.says = function() {
            return spec.saying();
        };

        return that;
    };

var myMammal = mammal({
    name: 'Herb',
    saying: function() {
        return 'Hello world!!!'
    }
});

console.log(myMammal.says());