spaces. </em></span>
    See <a class="link" href="http://gcc.gnu.org/ml/libstdc++/2003-08/msg00004.html" target="_top">this post</a>.
    This method fails the <span class="emphasis"><em>correctness</em></span> criteria.</p></li><li class="listitem"><p><span class="emphasis"><em>Extension: allow reopening on namespaces</em></span>: This would
    allow the debug mode to effectively alias the
    namespace <code class="code">std</code> to an internal namespace, such
    as <code class="code">__gnu_std_debug