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    <p>You could refactor or wrap <code>f</code> to return a new <code>X</code> instead of having it passed, since this would play pack expansion into the hand and make the function really concise:</p> <pre><code>template&lt;class T&gt; X fw(T const&amp; t){ X x; f(x, t); return x; } template&lt;class... Args&gt; void h(Args... args){ X xs[] = { fw(args)... }; g(xs, sizeof...(Args)); } </code></pre> <p><a href="http://liveworkspace.org/code/2667351a3a6fd53c54c1ba1abf6d8466">Live example.</a></p> <p>And if you could change <code>g</code> to just accept an <code>std::initializer_list</code>, it would get even more concise:</p> <pre><code>template&lt;class... Args&gt; void h(Args... args){ g({f(args)...}); } </code></pre> <p><a href="http://liveworkspace.org/code/363aeabcede4f39ac3bf9c14c71cc46a">Live example.</a> Or (maybe better), you could also provide just a wrapper <code>g</code> that forwards to the real <code>g</code>:</p> <pre><code>void g(X const*, unsigned){} void g(std::initializer_list&lt;X&gt; const&amp; xs){ g(xs.begin(), xs.size()); } template&lt;class... Args&gt; void h(Args... args){ g({f(args)...}); } </code></pre> <p><a href="http://liveworkspace.org/code/43b68fff53eac856768e60e855f05465">Live example.</a><br> <strong>Edit:</strong> Another option is using a temporary array:</p> <pre><code>template&lt;class T&gt; using Alias = T; template&lt;class T&gt; T&amp; as_lvalue(T&amp;&amp; v){ return v; } template&lt;class... Args&gt; void h(Args... args){ g(as_lvalue(Alias&lt;X[]&gt;{f(args)...}), sizeof...(Args)); } </code></pre> <p><a href="http://liveworkspace.org/code/6667474973ad0dba0fa8c0124f86d83c">Live example.</a> Note that the <code>as_lvalue</code> function is dangerous, the array still only lives until the end of the full expression (in this case <code>g</code>), so be cautious when using it. The <code>Alias</code> is needed since just <code>X[]{ ... }</code> is not allowed due to the language grammar.</p> <p>If all of that's not possible, you'll need recursion to access all elements of the <code>args</code> pack.</p> <pre><code>#include &lt;tuple&gt; template&lt;unsigned&gt; struct uint_{}; // compile-time integer for "iteration" template&lt;unsigned N, class Tuple&gt; void h_helper(X (&amp;)[N], Tuple const&amp;, uint_&lt;N&gt;){} template&lt;unsigned N, class Tuple, unsigned I = 0&gt; void h_helper(X (&amp;xs)[N], Tuple const&amp; args, uint_&lt;I&gt; = {}){ f(xs[I], std::get&lt;I&gt;(args)); h_helper(xs, args, uint_&lt;I+1&gt;()); } template&lt;typename... Args&gt; void h(Args... args) { static constexpr unsigned nargs = sizeof...(Args); X xs[nargs]; h_helper(xs, std::tie(args...)); g(xs, nargs); } </code></pre> <p><a href="http://liveworkspace.org/code/97da6870842756030cb7815367297e33">Live example.</a></p> <p><strong>Edit:</strong> Inspired by ecatmur's comment, I employed the <a href="http://loungecpp.wikidot.com/tips-and-tricks%3aindices">indices trick</a> to make it work with just pack expansion and with <code>f</code> and <code>g</code> as-is, without altering them.</p> <pre><code>template&lt;unsigned... Indices&gt; struct indices{ using next = indices&lt;Indices..., sizeof...(Indices)&gt;; }; template&lt;unsigned N&gt; struct build_indices{ using type = typename build_indices&lt;N-1&gt;::type::next; }; template &lt;&gt; struct build_indices&lt;0&gt;{ using type = indices&lt;&gt;; }; template&lt;unsigned N&gt; using IndicesFor = typename build_indices&lt;N&gt;::type; template&lt;unsigned N, unsigned... Is, class... Args&gt; void f_them_all(X (&amp;xs)[N], indices&lt;Is...&gt;, Args... args){ int unused[] = {(f(xs[Is], args), 1)...}; (void)unused; } template&lt;class... Args&gt; void h(Args... args){ static constexpr unsigned nargs = sizeof...(Args); X xs[nargs]; f_them_all(xs, IndicesFor&lt;nargs&gt;(), args...); g(xs, nargs); } </code></pre> <p><a href="http://liveworkspace.org/code/cbeb0698d38787368557e7b60e283220">Live example.</a></p>
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    1. CO`X xs[] = { f(args)... };` is pretty cool. Actually the specific case of my problem is MySQL's MYSQL_BIND (= X) structure and I am not sure if it can be copied. But if it can that's very nice.
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    2. COAdded live examples to all code snippets, fixed several typos and provided a wrapper option for `g`. Hope something of it does help with your MYSQL stuff. :)
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    3. COActually if you look at code sample here: http://dev.mysql.com/doc/refman/5.5/en/mysql-stmt-execute.html. The MYSQL_BIND struct can be copied so I think your solution will work.
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