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    <p>Yes you can, it just take some massaging ;)</p> <p>The trick is to use composition: instead of iterating over the container directly, you "zip" it with an index along the way.</p> <p>Specialized zipper code:</p> <pre><code>template &lt;typename T&gt; struct iterator_extractor { typedef typename T::iterator type; }; template &lt;typename T&gt; struct iterator_extractor&lt;T const&gt; { typedef typename T::const_iterator type; }; template &lt;typename T&gt; class Indexer { public: class iterator { typedef typename iterator_extractor&lt;T&gt;::type inner_iterator; typedef typename std::iterator_traits&lt;inner_iterator&gt;::reference inner_reference; public: typedef std::pair&lt;size_t, inner_reference&gt; reference; iterator(inner_iterator it): _pos(0), _it(it) {} reference operator*() const { return reference(_pos, *_it); } iterator&amp; operator++() { ++_pos; ++_it; return *this; } iterator operator++(int) { iterator tmp(*this); ++*this; return tmp; } bool operator==(iterator const&amp; it) const { return _it == it._it; } bool operator!=(iterator const&amp; it) const { return !(*this == it); } private: size_t _pos; inner_iterator _it; }; Indexer(T&amp; t): _container(t) {} iterator begin() const { return iterator(_container.begin()); } iterator end() const { return iterator(_container.end()); } private: T&amp; _container; }; // class Indexer template &lt;typename T&gt; Indexer&lt;T&gt; index(T&amp; t) { return Indexer&lt;T&gt;(t); } </code></pre> <p>And using it:</p> <pre><code>#include &lt;iostream&gt; #include &lt;iterator&gt; #include &lt;limits&gt; #include &lt;vector&gt; // Zipper code here int main() { std::vector&lt;int&gt; v{1, 2, 3, 4, 5, 6, 7, 8, 9}; for (auto p: index(v)) { std::cout &lt;&lt; p.first &lt;&lt; ": " &lt;&lt; p.second &lt;&lt; "\n"; } } </code></pre> <p>You can see it at <a href="http://ideone.com/rAcaZ">ideone</a>, though it lacks the for-range loop support so it's less pretty.</p> <p><strong>EDIT:</strong></p> <p>Just remembered that I should check Boost.Range more often. Unfortunately no <code>zip</code> range, but I did found a perl: <a href="http://www.boost.org/doc/libs/1_49_0/libs/range/doc/html/range/reference/adaptors/reference/indexed.html"><code>boost::adaptors::indexed</code></a>. However it requires access to the iterator to pull of the index. Shame :x</p> <p>Otherwise with the <a href="http://www.boost.org/doc/libs/1_49_0/libs/range/doc/html/range/reference/ranges/counting_range.html"><code>counting_range</code></a> and a generic <code>zip</code> I am sure it could be possible to do something interesting...</p> <p>In the ideal world I would imagine:</p> <pre><code>int main() { std::vector&lt;int&gt; v{1, 2, 3, 4, 5, 6, 7, 8, 9}; for (auto tuple: zip(iota(0), v)) { std::cout &lt;&lt; tuple.at&lt;0&gt;() &lt;&lt; ": " &lt;&lt; tuple.at&lt;1&gt;() &lt;&lt; "\n"; } } </code></pre> <p>With <code>zip</code> automatically creating a view as a range of tuples of references and <code>iota(0)</code> simply creating a "false" range that starts from <code>0</code> and just counts toward infinity (or well, the maximum of its type...).</p>
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    1. POFind position of element in C++11 range-based for loop?
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    1. USMatthieu M.
    1. USMatthieu M.
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    1. COThis provides a wealth of useful information. Thanks. I'll play around with the code. As I mentioned above, the "index" code is what I would like the language to provide.
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      1. USFred Finkle
    2. COHow about `counting_range` (or [`boost::counting_iterator`](http://www.boost.org/libs/iterator/doc/counting_iterator.html)) + [`boost::zip_iterator`](http://www.boost.org/libs/iterator/doc/zip_iterator.html)?
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    3. CO@ildjarn: Yes, Boost.Iterators has the building blocks (it seems), however there is no corresponding range, which is annoying.
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