function init() {
    if ( !atomicHelpers.setInitFlag( _baseElement ) ) {
      return UNDEFINED;
    }
    _cachedFields = _cacheFields();
    _formElement.addEventListener( 'submit', _onSubmit );

    return this;
  }
/**
   * @returns {FormSubmit|undefined} An instance,
   *   or undefined if it was already initialized.
   */
@returns {FormSubmit|undefined} An instance,
or undefined if it was already initialized.
@returns { FormSubmit|undefined } An instance or undefined if it was already initialized .
function init() {
    if ( !atomicHelpers.setInitFlag( _baseElement ) ) {
      return UNDEFINED;
    }
    _cachedFields = _cacheFields();
    _formElement.addEventListener( 'submit', _onSubmit );
    return this;
  }
function init ( ) { if ( ! atomicHelpers . setInitFlag ( _baseElement ) ) { return UNDEFINED ; } _cachedFields = _cacheFields ( ) ; _formElement . addEventListener ( 'submit' , _onSubmit ) ; return this ; }
@returns {FormSubmit|undefined} An instance,
   or undefined if it was already initialized.
@returns { FormSubmit|undefined } An instance or undefined if it was already initialized .