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    <p>Luc's solution is clean and straightforward, but sorely lacks fun.<br> Because there is only one proper way to use variadic templates and it is to abuse them to do crazy overcomplicated metaprogramming stuff :)</p> <p>Like this :</p> <pre><code>template &lt;class T, size_t... Indx, class... Ts&gt; std::array&lt;T, sizeof...(Indx)&gt; split_array_range_imp(pack_indices&lt;Indx...&gt; pi, Ts... ts) { return std::array&lt;T, sizeof...(Indx)&gt;{get&lt;Indx&gt;(ts...)...}; //TADA } template &lt;class T, size_t begin, size_t end, class... Ts&gt; std::array&lt;T, end - begin&gt; split_array_range(Ts... ts) { typename make_pack_indices&lt;end, begin&gt;::type indices; return split_array_range_imp&lt;T&gt;(indices, ts...); } template &lt;size_t N&gt; struct DoubleArray { std::array &lt;int, N&gt; p, q; template &lt;typename ... Ts&gt; DoubleArray (Ts ... ts) : p( split_array_range&lt;int, 0 , sizeof...(Ts) / 2 &gt;(ts...) ), q( split_array_range&lt;int, sizeof...(Ts) / 2, sizeof...(Ts) &gt;(ts...) ) { } }; int main() { DoubleArray&lt;3&gt; mya{1, 2, 3, 4, 5, 6}; std::cout &lt;&lt; mya.p[0] &lt;&lt; "\n" &lt;&lt; mya.p[1] &lt;&lt; "\n" &lt;&lt; mya.p[2] &lt;&lt; std::endl; std::cout &lt;&lt; mya.q[0] &lt;&lt; "\n" &lt;&lt; mya.q[1] &lt;&lt; "\n" &lt;&lt; mya.q[2] &lt;&lt; std::endl; } </code></pre> <p>It is quite short, except that we need to code some helper :</p> <p>First we need the structure make_pack_indices, which is used to generate a range of integer at compile-time. For example <code>make_pack_indices&lt;5, 0&gt;::type</code> is actually the type <code>pack_indices&lt;0, 1, 2, 3, 4&gt;</code></p> <pre><code>template &lt;size_t...&gt; struct pack_indices {}; template &lt;size_t Sp, class IntPack, size_t Ep&gt; struct make_indices_imp; template &lt;size_t Sp, size_t ... Indices, size_t Ep&gt; struct make_indices_imp&lt;Sp, pack_indices&lt;Indices...&gt;, Ep&gt; { typedef typename make_indices_imp&lt;Sp+1, pack_indices&lt;Indices..., Sp&gt;, Ep&gt;::type type; }; template &lt;size_t Ep, size_t ... Indices&gt; struct make_indices_imp&lt;Ep, pack_indices&lt;Indices...&gt;, Ep&gt; { typedef pack_indices&lt;Indices...&gt; type; }; template &lt;size_t Ep, size_t Sp = 0&gt; struct make_pack_indices { static_assert(Sp &lt;= Ep, "__make_tuple_indices input error"); typedef typename make_indices_imp&lt;Sp, pack_indices&lt;&gt;, Ep&gt;::type type; }; </code></pre> <p>We also need a get() function, very similar to std::get for tuple, such as <code>std::get&lt;N&gt;(ts...)</code> return the Nth element of a parameters pack.</p> <pre><code>template &lt;class R, size_t Ip, size_t Ij, class... Tp&gt; struct Get_impl { static R&amp; dispatch(Tp...); }; template&lt;class R, size_t Ip, size_t Jp, class Head, class... Tp&gt; struct Get_impl&lt;R, Ip, Jp, Head, Tp...&gt; { static R&amp; dispatch(Head&amp; h, Tp&amp;... tps) { return Get_impl&lt;R, Ip, Jp + 1, Tp...&gt;::dispatch(tps...); } }; template&lt;size_t Ip, class Head, class... Tp&gt; struct Get_impl&lt;Head, Ip, Ip, Head, Tp...&gt; { static Head&amp; dispatch(Head&amp; h, Tp&amp;... tps) { return h; } }; template &lt;size_t Ip, class ... Tp&gt; typename pack_element&lt;Ip, Tp...&gt;::type&amp; get(Tp&amp;... tps) { return Get_impl&lt;typename pack_element&lt;Ip, Tp...&gt;::type, Ip, 0, Tp...&gt;::dispatch(tps...); } </code></pre> <p>But to build get() we also need a pack_element helper structure, again very similar to std::tuple_element, such as <code>pack_element&lt;N, Ts...&gt;::type</code> is the Nth type of the parameters pack.</p> <pre><code>template &lt;size_t _Ip, class _Tp&gt; class pack_element_imp; template &lt;class ..._Tp&gt; struct pack_types {}; template &lt;size_t Ip&gt; class pack_element_imp&lt;Ip, pack_types&lt;&gt; &gt; { public: static_assert(Ip == 0, "tuple_element index out of range"); static_assert(Ip != 0, "tuple_element index out of range"); }; template &lt;class Hp, class ...Tp&gt; class pack_element_imp&lt;0, pack_types&lt;Hp, Tp...&gt; &gt; { public: typedef Hp type; }; template &lt;size_t Ip, class Hp, class ...Tp&gt; class pack_element_imp&lt;Ip, pack_types&lt;Hp, Tp...&gt; &gt; { public: typedef typename pack_element_imp&lt;Ip-1, pack_types&lt;Tp...&gt; &gt;::type type; }; template &lt;size_t Ip, class ...Tp&gt; class pack_element { public: typedef typename pack_element_imp&lt;Ip, pack_types&lt;Tp...&gt; &gt;::type type; }; </code></pre> <p>And here we go.<br> Actually I don't really understand why pack_element and get() are not in the standard library already. Those helpers are present for std::tuple, why not for parameters pack ?</p> <p>Note : My implementation of pack_element and make_pack_indices is a direct transposition of std::tuple_element and __make_tuple_indices implementation found in libc++.</p>
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    1. POsplit variadic template arguments
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    1. USThomas Petit
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    1. COI think that this is the cleanest solution. The more I look at it, the more I like it.
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    2. COIMO this should be the accepted answer because this is the right way to do it. Copying elements during runtime has the same effect, but comes with a performance penalty that is completely avoidable.
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