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    copied!<p>This can be done fairly easily using a <code>std::tuple</code> to specify your list of types. All we need to do is declare the primary template to take two parameters, then create a partial specialization where those type parameters are tuples. In the partial specialization, we can use the argument deduction to capture the template parameters of the tuple and re-use them for our purposes. We could create a new template for the purposes of specifying the list of types (i.e. <code>Types&lt;int,double&gt;</code>), but a tuple is especially nice in this case because you need to have a way to access the the individual rows anyway, and a <code>std::tuple</code> provides a built-in way to do this through <code>std::get&lt;i&gt;</code>. Using the tuple for the template parameters may make it more obvious that you use <code>std::get</code> to access the rows.</p> <p>Here's a complete example:</p> <pre><code>#include &lt;string&gt; #include &lt;tuple&gt; #include &lt;vector&gt; // primary template template &lt;typename RowTuple,typename RowInfoTuple&gt; struct Rows; // variadic partial specialization template &lt;typename... RowTypes,typename... RowInfoTypes&gt; struct Rows&lt;std::tuple&lt;RowTypes...&gt;,std::tuple&lt;RowInfoTypes...&gt;&gt; { // use variadic expansion to make a tuple of vectors std::tuple&lt;std::vector&lt;RowTypes&gt;...&gt; rows; std::tuple&lt;RowInfoTypes...&gt; rowinfos; }; struct rss_feed { }; int main(int,char**) { Rows&lt; std::tuple&lt;double,int&gt;, std::tuple&lt;std::string,rss_feed&gt; &gt; data; std::get&lt;0&gt;(data.rows).push_back(1.5); std::get&lt;1&gt;(data.rows).push_back(2); std::get&lt;0&gt;(data.rowinfos) = "info"; std::get&lt;1&gt;(data.rowinfos) = rss_feed(); return 0; } </code></pre>
 

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