oft Windows 98.</li>
    <li>John Maddock and Howard Hinnant have submitted a &quot;compressed_pair&quot;
        library to Boost, which uses a technique similar to the
        one described here to hold references. Their pair also
        uses type traits to determine if any of the types are
        empty, and will derive instead of contain to conserve
        space -- hence the name &quot;compressed&quot;.</li>
    <li>This is actually an issue with the C++ Core Language
        Working Group (issue #106