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    copied!<p>You can achieve what you want by encapsulating the variadic argument pack in a tuple and later using the following two helper template structs to forward the actual variadic arguments:</p> <pre><code>template&lt;typename PackR, typename PackL&gt; struct cat; template&lt;typename ...R, typename ...L&gt; struct cat&lt;std::tuple&lt;R...&gt;, std::tuple&lt;L...&gt;&gt; { typedef std::tuple&lt;R..., L...&gt; type; }; </code></pre> <p>and</p> <pre><code>template&lt;typename Pack, template&lt;typename ...T&gt; class Receiver&gt; struct Unpack; template&lt;typename ...Args, template&lt;typename ...T&gt; class Receiver&gt; struct Unpack&lt;std::tuple&lt;Args...&gt;, Receiver&gt; { typedef Receiver&lt;Args...&gt; type; }; </code></pre> <p>your code sample would look like this:</p> <pre><code>#include &lt;set&gt; #include &lt;cstdint&gt; #include &lt;tuple&gt; template&lt;typename PackR, typename PackL&gt; struct Cat; template&lt;typename ...R, typename ...L&gt; struct Cat&lt;std::tuple&lt;R...&gt;, std::tuple&lt;L...&gt;&gt; { typedef std::tuple&lt;R..., L...&gt; type; }; template&lt;typename Pack, template&lt;typename ...T&gt; class Receiver&gt; struct Unpack; template&lt;typename ...Args, template&lt;typename ...T&gt; class Receiver&gt; struct Unpack&lt;std::tuple&lt;Args...&gt;, Receiver&gt; { typedef Receiver&lt;Args...&gt; type; }; template&lt;typename ...Args&gt; struct Forward { //typedef Args... args; // Problem here!! typedef std::tuple&lt;Args...&gt; args; // Workaround static const std::size_t size = sizeof...(Args); }; template&lt;typename S, typename T, template&lt;typename ...SArgs&gt; class SCont, template&lt;typename ...TArgs&gt; class TCont, typename SForward = Forward&lt;&gt; , typename TForward = Forward&lt;&gt;&gt; class Bimap { //typedef SCont&lt;S, typename SForward::args&gt; left_type; //typedef TCont&lt;T, typename TForward::args&gt; right_type; typedef typename Unpack&lt;typename Cat&lt;std::tuple&lt;S&gt;, typename SForward::args&gt;::type, SCont&gt;::type left_type; //Workaround typedef typename Unpack&lt;typename Cat&lt;std::tuple&lt;T&gt;, typename TForward::args&gt;::type, TCont&gt;::type right_type; //Workaround template&lt;typename LeftIt, typename RightIt&gt; struct Relation; // to be implemented typedef Relation&lt;typename left_type::const_iterator, typename right_type::const_iterator&gt; relation_type; }; int main() { Bimap&lt;int, int, std::set, std::set, Forward&lt;std::less&lt;int&gt;&gt; , Forward&lt;std::greater&lt;int&gt;&gt;&gt; x; } </code></pre> <p>which compiles just fine under gcc 4.6.0</p>
 

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