ist
    {
      // ...
     };
} // namespace std
</pre><p>In debug mode we include the release-mode container (which is now
defined in the namespace <code class="code">__cxx1998</code>) and also the
debug-mode container. The debug-mode container is defined within the
namespace <code class="code">__debug</code>, which is associated with namespace
<code class="code">std</code> via the C++11 namespace association language feature.  This
method allows the debug and release versions of the same component to
coe