private function loadParser(ContainerBuilder $container)
    {
        $definition = new Definition('Behat\Gherkin\Parser', array(
            new Reference('gherkin.lexer')
        ));
        $container->setDefinition('gherkin.parser', $definition);

        $definition = new Definition('Behat\Gherkin\Lexer', array(
            new Reference('gherkin.keywords')
        ));
        $container->setDefinition('gherkin.lexer', $definition);
    }