/* returns true if address is a valid email address */
function validate_email(address){
  re = /^(([^<>()[\]\\.,;:\s@\"]+(\.[^<>()[\]\\.,;:\s@\"]+)*)|(\".+\"))@((\[(2([0-4]\d|5[0-5])|1?\d{1,2})(\.(2([0-4]\d|5[0-5])|1?\d{1,2})){3} \])|(([a-zA-Z\-0-9]+\.)+[a-zA-Z]{2,}))$/;
  return re.test(address);
}

/* returns true if val is a valid number */
function validate_number(val) {
  re = /^(-|\+)?\d+$/;
  return re.test(val);
}