pose. We take the <code class="computeroutput"><span class="special">&gt;&gt;</span></code>
      operator, with arrows pointing to the right, to mean "is followed by".
      Thus we write:
    </p>
<pre class="programlisting"><span class="identifier">a</span> <span class="special">&gt;&gt;</span> <span class="identifier">b</span>
</pre>
<p>
      The alternative operator <code class="computeroutput"><span class="special">|</span></code> and
      the parentheses <code class="computeroutput"><span class="sp