   </span>
      <p class="shortcomment cmt"><code>na</code> provides syntactic sugar for constructing primitives recognized as NA.</p><div class="fullcomment"><div class="comment cmt"><p><code>na</code> provides syntactic sugar for constructing primitives recognized as NA.
A use case is be:</p><pre>Vec[<span class="std">Int</span>](<span class="num">1</span>,<span class="num">2</span>,na,<span class="num">4</span>)</pre><p><code>na</code> will implicitly convert to a primitive having the designated missing