de class="computeroutput"><span class="keyword">float</span></code>, <code class="computeroutput"><span class="keyword">double</span></code> and <code class="computeroutput"><span class="keyword">long</span>
      <span class="keyword">double</span></code> versions of the constant, plus
      a decimal digit string representation correct to 100 decimal digits, and all
      the meta-programming machinery needed to select between them.
    </p>
<p>
      The result of an expanded macro for Pi is shown below.