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    <h3>TL;DR</h3> <pre><code>template&lt;typename T, int N&gt; using raw_array = T[N]; auto &amp;&amp;z = raw_array&lt;int,5&gt;{}; </code></pre> <hr> <p>Your example of <code>auto z = int[5];</code> isn't legal any more than <code>auto z = int;</code> is, simply because a type is not a valid initializer. You can write: <code>auto z = int{};</code> because <code>int{}</code> is a valid initializer.</p> <p>Once one realizes this, the next attempt would be:</p> <pre><code>auto z = int[5]{}; </code></pre> <p>Note that your <code>int y[5]</code> does not have any initializer. If it had then you would have jumped straight here.</p> <p>Unfortunately this does not work either for obscure syntax reasons. Instead you must find a legal way to name the array type in an initializer. For example, a typedef name can be used in an initializer. A handy reusable <em>template type alias</em> eliminates the burdensome requirement of a new typedef for every array type:</p> <pre><code>template&lt;typename T, int N&gt; using raw_array = T[N]; auto z = raw_array&lt;int,5&gt;{}; </code></pre> <hr> <p>Aside: You can use template type aliases to fix the weird 'inside-out' syntax of C++, allowing you to name any compound type in an orderly, left-to-right fashion, by using <a href="https://groups.google.com/a/isocpp.org/forum/?fromgroups#!searchin/std-proposals/left$20to$20right$20type$20syntax/std-proposals/xDQR3y5uTZ0/VKmOiLRzHqkJ" rel="nofollow noreferrer">this proposal</a>.</p> <hr> <p>Unfortunately due to the design bug in C and C++ which causes array-to-pointer conversions at the drop of a hat, the deduced type of the variable <code>z</code> is <code>int*</code> rather <code>int[5]</code>. The resulting variable becomes a dangling pointer when the temporary array is destroyed.</p> <p>C++14 introduces <code>decltype(auto)</code> which uses different type deduction rules, correctly deducing an array type:</p> <pre><code>decltype(auto) z = raw_array&lt;int,5&gt;{}; </code></pre> <p>But now we run into another design bug with arrays; they do not behave as proper objects. You can't assign, copy construct, do pass by value, etc., with arrays. The above code is like saying:</p> <pre><code>int g[5] = {}; int h[5] = g; </code></pre> <p>By all rights this should work, but unfortunately built-in arrays <a href="https://stackoverflow.com/a/10253277/365496">behave bizarrely</a> in C and C++. In our case, the specific problem is that arrays are not allowed to have just any kind of initializer; they are strictly limited to using initializer lists. An array temporary, initialized by an initializer list, is not itself an initializer list.</p> <hr> <h3>Answer 1:</h3> <p>At this point Johannes Schaub makes the excellent suggestion that we can use temporary lifetime extension.</p> <pre><code>auto &amp;&amp;z = raw_array&lt;int,5&gt;{}; </code></pre> <p><code>decltype(auto)</code> isn't needed because the addition of <code>&amp;&amp;</code> changes the deduced type, so Johannes Schaub's suggestion works in C++11. This also avoids the limitation on array initializers because we're initializing a reference instead of an array.</p> <p>If you want the array to deduce its length from an initializer, you can use an incomplete array type:</p> <pre><code>template&lt;typename T&gt; using unsized_raw_array = T[]; auto &amp;&amp;z = unsized_raw_array&lt;int&gt;{1, 2, 3}; </code></pre> <hr> <p>Although the above does what you want you may prefer to avoid raw arrays entirely, due to the fact that raw arrays do not behave like proper C++ objects, and the obscurity of their behavior and the techniques used above.</p> <h3>Answer 2:</h3> <p>The <code>std::array</code> template in C++11 does act like a proper object, including assignment, being passable by value, etc., and just generally behaving sanely and consistently where built-in arrays do not.</p> <pre><code>auto z = std::array&lt;int,5&gt;{}; </code></pre> <p>However, with this you miss out on being able to have the array type infer its own length from an initializer. Instead You can write a <code>make_array</code> template function that does the inference. Here's a really simple version I haven't tested and which doesn't do things you might want, such as verify that all the arguments are the same type, or let you explicitly specify the type.</p> <pre><code>template&lt;typename... T&gt; std::array&lt;typename std::common_type&lt;T...&gt;::type, sizeof...(T)&gt; make_array(T &amp;&amp;...t) { return {std::forward&lt;T&gt;(t)...}; } auto z = make_array(1,2,3,4,5); </code></pre>
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    1. COBut I thought he wanted it to be uninitialized like `y`, or default initialized like `int{}`. Are you saying `int[5]{}` would work?
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    2. CO@jxh Yes, you can have a default initializer: `auto z = raw_array<int,100>{};`
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    3. COI can't get your first success case to work: http://ideone.com/Hn7X6q
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