title: Autowire String parameter in symfony
body: <p>How can I wire a String parameter in Symfony 3.4?</p>
  
  <p>I have simple service and I want to wire a <code>url</code> parameter specified in <code>parameters.yml</code>:</p>
  
  <pre><code>namespace AppBundle\Service;
  
  use Psr\Log\LoggerInterface;
  
  class PythonService {
  
      private $logger;
      private $url;
  
      /**
       * @param LoggerInterface $logger
       * @param String $url
       */
      public function __construct(LoggerInterface $logger, String $url) {
          $this-&gt;logger = $logger;
          $this-&gt;url = $url;
      }
  }
  </code></pre>
  
  <p>My <code>service.yml</code> looks like:</p>
  
  <pre><code>AppBunde\Services\PythonService:
      arguments: ['@logger', '%url%']
  </code></pre>
  
  <p>But I am getting error:</p>
  
  <pre><code>Cannot autowire service "AppBundle\Service\PythonService": argument "$url" of method "__construct()" is type-hinted "string", you should configure its value explicitly.
  </code></pre>
  
  <p>I tried also manually specify parameters:</p>
  
  <pre><code>AnalyticsDashboardBunde\Services\PythonService:
      arguments:
          $logger: '@logger'
          $url: '%session_memcached_host%'
  </code></pre>
  
  <p>This gives me following error:</p>
  
  <pre><code>Invalid service "AppBundle\Services\PythonService": class "AppBundle\Services\PythonService" does not exist.
  </code></pre>