em>,<em class="replaceable"><code>upper-bound</code></em>)
[<em class="replaceable"><code>lower-bound</code></em>,<em class="replaceable"><code>upper-bound</code></em>]
empty
</pre><p>
   The parentheses or brackets indicate whether the lower and upper bounds
   are exclusive or inclusive, as described previously.
   Notice that the final pattern is <code class="literal">empty</code>, which
   represents an empty range (a range that contains no points).
  </p><p>
   The <em class="replaceable"><code>lower-b