title: Performing an SQL cast in Slick
body: <p>Using Slick, I know I can map an sql function to a scala value like this:</p>
  
  <pre><code>val toChar = SimpleFunction.binary[Date, String, String]("TO_CHAR")
  </code></pre>
  
  <p>and call it like this:</p>
  
  <pre><code>toChar.apply(dateColumn, "yyyy-MM-dd")
  </code></pre>
  
  <p>Is there a way to map the <code>CAST</code> function? It has a different form: <code>CAST(dateColumn AS CHAR)</code></p>
  
  <p>Thanks!</p>