title: How do you manipulate a list of tuples in SML?
body: <p>I'm new to SML, and I was wondering how to get an element in a list of tuples. For example, in the list <code>[("abc", 4), ("def", 6)]</code>, how could you extract <code>"abc"</code>? I've tried </p>
  
  <pre><code>x::xs =&gt; #1(x)
  </code></pre>
  
  <p>but I keep getting "unresolved flex record". Any suggestions?</p>