How to use the aurelia-validation.Validator function in aurelia-validation

function validation() {
  var ValidatorClass = arguments.length > 0 && arguments[0] !== undefined ? arguments[0] : _aureliaValidation.Validator;

  return function (target) {
    OrmMetadata.forTarget(target).put('validation', ValidatorClass);
  };
}

function validation() {
  var ValidatorClass = arguments.length > 0 && arguments[0] !== undefined ? arguments[0] : _aureliaValidation.Validator;

  return function (target) {
    OrmMetadata.forTarget(target).put('validation', ValidatorClass);
  };
}

function configure(config) {
  config.container.registerInstance(_aureliaValidation.Validator, new Validator());
}