title: Removing multiple character types from a string
body: <p>Is this an acceptable approach for removing multiple character types from a string or is there a better (more efficient way)? The <code>"ilr".contains(_)</code> bit feels a little like cheating considering it will be done for each and every character, but then again, maybe this is the right way. Is there a faster or more efficient way to do this?</p>
  
  <pre><code>val sentence = "Twinkle twinkle little star, oh I wander what you are"
  
  val words = sentence.filter(!"ilr".contains(_))   
  
  // Result: "Twnke twnke tte sta, oh I wande what you ae"
  </code></pre>