function PhoneNumber (s) {this.number = s.match(/\d/g)}
PhoneNumber.prototype.toString = function () {return ['(', this.number[0], this.number[1], this.number[2], ')', this.number[3], this.number[4], this.number[5], '-', this.number[6], this.number[7], this.number[8], this.number[9]].join('')}