Object.defineProperty Sham For IE  

<script src="path/to/object-defineproperty-ie.js" type="text/javascript"></script>
<script type="text/javascript">
    var oldObj = Object.defineProperty({}, 'string', {
        value: 'Ambit Tsai',
        enumerable: true
    });
    // oldObj => {string: "Ambit Tsai"}

    var newObj = Object.defineProperties(oldObj, {
        getter: {
            get: function () {
                return this.string;
            }
        },
        setter: {
            set: function (value) {
                this.string = value;
            }
        }
    });
    // newObj => {
    //     getter: "Ambit Tsai",
    //     setter: undefined,
    //     string: "Ambit Tsai"
    // }

    var desc = Object.getOwnPropertyDescriptor(newObj, 'string');
    // desc => {
    //     configurable: false,
    //     enumerable: true,
    //     value: "Ambit Tsai",
    //     writable: false
    // }
</script>