src/NoCaptchaServiceProvider.php
private function registerFormMacros($app)
    {
        if ($app->bound('form')) {
            $app['form']->macro('captcha', function($name = null, array $attributes = []) use ($app) {
                return $app[Contracts\NoCaptcha::class]->display($name, $attributes);
            });
        }
    }
private function registerFormMacros($app)
    {
        if ($app->bound('form')) {
            $app['form']->macro('captcha', function($name = null, array $attributes = []) use ($app) {
                return $app[Contracts\NoCaptcha::class]->display($name, $attributes);
            });
        }
    }
Register Form Macros.

@param  \Illuminate\Foundation\Application  $app