ode> is the supertype and <code class="computeroutput"><span class="identifier">T</span></code> the subtype; otherwise, <code class="computeroutput"><span class="identifier">T</span></code> is the supertype and <code class="computeroutput"><span class="identifier">S</span></code>
        the subtype.
      </p>
<p>
        For example:
      </p>
<div class="blockquote"><blockquote class="blockquote"><p>
          <code class="computeroutput"><span class="identifier">R</span><span class="special">(</span><s