title: rails match ending of string in params
body: <p>I am receiving params with keys like: </p>
  
  <pre><code>params["guest1_member1"]
  params["guest2_member1"]
  params["guest3_member2"]
  params["guest4_member2"]
  </code></pre>
  
  <p>Is there some regex way to get params containing <code>_member1</code>?</p>
  
  <p>Something like:</p>
  
  <pre><code>params["*_member1"]
  </code></pre>