https://svn.boost.org/trac10/ticket/4229 <p> Please provide an at&lt;&gt; (or at-like) implementation for associative containers that accepts the value 'returned' by order&lt;&gt;. Motivation/a description of an example use case can be found in the following post: <a class="ext-link" href="http://lists.boost.org/Archives/boost/2010/05/166358.php"><span class="icon">​</span>http://lists.boost.org/Archives/boost/2010/05/166358.php</a>. </p> en-us /htdocs/site/boost.png https://svn.boost.org/trac10/ticket/4229 Trac 1.4.3