 second expects a <code class="computeroutput"><span class="identifier">DefaultConstructible</span></code>
          class. Its default constructor will be used as set-up function and its
          destructor as a tear-down function.
        </p>
<p>
          The third form requires a class with one-argument public constructor. Argument
          <code class="computeroutput"><span class="identifier">arg</span></code> is forwarded to the
          constructor.
        </p>
<p>
          For the second and t