title: SML doesn't acknowledge ord or chr
body: <p>I'm using this example from <a href="http://www.soc.napier.ac.uk/course-notes/sml/tut1.htm" rel="nofollow">"Gentle Intro to ML"</a></p>
  
  <pre><code> fun incFirst s = chr(ord s + 1) ^ substring(s, 1, size s -1);
  </code></pre>
  
  <p>But my "Standard ML of New Jersey v110.76 [built: Tue Oct 22 14:04:11 2013]" doesn't like it.</p>
  
  <blockquote>
    <p>Error: operator and operand don't agree [tycon mismatch]</p>
  </blockquote>
  
  <p>I can't even do this:</p>
  
  <pre><code>&gt; ord "c";
  </code></pre>
  
  <p>without getting an error</p>
  
  <blockquote>
    <p>Error: operator and operand don't agree [tycon mismatch]</p>
  </blockquote>
  
  <p>It doesn't recognize</p>
  
  <pre><code>load "Char";
  </code></pre>
  
  <p>either. What am I doing wrong?</p>