Here you can find the source of after(other)
Date.prototype.after = function(other) { return this.compareTo(other) > 0; }
Date.prototype.isAfterDate = function (d) { var tDate = new Date(this.getFullYear(), this.getMonth(), this.getDate()); var pDate = new Date(d.getFullYear(), d.getMonth(), d.getDate()); return tDate > pDate