title: attaching an error to validator in laravel 5
body: <p>I'm using <code>Validator Facade</code> , here's the code</p>
  
  <pre><code>$req = Request::all();
  $rules = [
      'name'=&gt;'required|min:3|max:20'
  ];
  $validator = Validator::make($req, $rules);
  
  if(/*another problem*/){
      // ??
  }      
  
  if ($validator-&gt;fails()) {
      return redirect()-&gt;back()-&gt;withErrors($validator)-&gt;withInput();
  }
  </code></pre>
  
  <p>I want to keep the errors that the Laravel's <code>Validator</code> make's It self and attach some others to them (If needed).
  So for example If there was nothing wrong with the <code>name</code> input but my <code>if</code> statement found an error, the <code>Validator</code> would fail.</p>