<p>
                      Repeat the generator <code class="computeroutput"><span class="identifier">a</span></code>
                      exactly <code class="computeroutput"><span class="identifier">num</span></code>
                      times. This generator succeeds as long as its embedded generator
                      <code class="computeroutput"><span class="identifier">a</span></code> does not
                      fail and as long as the associated attribute (container) contains
                 