title: Route pattern error: cannot reference variable name more than once
body: <p>I have the following route in web.php</p>
  
  <pre><code>Route::resource("api/companies/{kind}", "api\Companies", ['only' =&gt; ['index', 'create', 'store', 'show']] );
  </code></pre>
  
  <p>Having that route will give me an error:</p>
  
  <pre><code>Route pattern "/api/companies/{kind}/{{kind}}" cannot reference variable name "kind" more than once.
  </code></pre>
  
  <p>However, if I remove the 'show' option from the route, it works:</p>
  
  <pre><code>Route::resource("api/companies/{kind}", "api\Companies", ['only' =&gt; ['index', 'create', 'store']] );
  </code></pre>
  
  <p>Can't see what's wrong with my route, and what's the relationship with the 'show' option.</p>