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  1. PO
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    <p>This might do what you want. It uses <code>std::transform</code> internally, which basically does the whole work. The function I wrote is nothing more than a simple wrapper for containers (not working with C-style arrays, that would require some additional type traits):</p> <pre><code>#include &lt;vector&gt; #include &lt;algorithm&gt; #include &lt;type_traits&gt; // // Takes an iterable, applies a function to every element, // and returns a vector of the results // template &lt;typename T, typename Func&gt; auto map_container(const T&amp; iterable, Func&amp;&amp; func) -&gt; std::vector&lt;decltype(func(std::declval&lt;typename T::value_type&gt;()))&gt; { // Some convenience type definitions typedef decltype(func(std::declval&lt;typename T::value_type&gt;())) value_type; typedef std::vector&lt;value_type&gt; result_type; // Prepares an output vector of the appropriate size result_type res(iterable.size()); // Let std::transform apply `func` to all elements // (use perfect forwarding for the function object) std::transform( begin(iterable), end(iterable), res.begin(), std::forward&lt;Func&gt;(func) ); return res; } </code></pre> <p>However, notice that your lambda should take a reference to <code>const</code>, or better should take its argument by value in the case of <code>int</code>. </p> <p>Also, I renamed the function from <code>map</code> into <code>map_container</code>: it is a bad programming practice to reuse names of standard containers of the C++ Standard Library for functions, variables, or anything else in your program.</p> <p>For me, this gives the desired output:</p> <pre><code>#include &lt;iostream&gt; int main() { std::vector&lt;int&gt; intVector; intVector.push_back(1); intVector.push_back(2); auto v = map_container(intVector, [] (int value) { return value + 1; }); for (int i : v) { std::cout &lt;&lt; i &lt;&lt; " "; } } </code></pre>
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    1. COFails to work for `int x[5] = {0};` a basic C array. This is iterable, as demonstrated by `for( auto i:x ) { std::cout << i << " "; }`
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      1. USYakk - Adam Nevraumont
    2. CO@Yakk: Fixed it.
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    3. COHow so? You still examine `T::value_type` directly.
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