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    <p>Boost has <a href="http://www.boost.org/doc/libs/1_41_0/libs/iterator/doc/counting_iterator.html" rel="noreferrer">counting_iterator</a> as far as I know, which seems to allow only incrementing in steps of 1. For full xrange functionality you might need to implement a similar iterator yourself.</p> <p>All in all it could look like this (edit: added an iterator for the third overload of xrange, to play around with boost's iterator facade):</p> <pre><code>#include &lt;iostream&gt; #include &lt;boost/iterator/counting_iterator.hpp&gt; #include &lt;boost/range/iterator_range.hpp&gt; #include &lt;boost/foreach.hpp&gt; #include &lt;boost/iterator/iterator_facade.hpp&gt; #include &lt;cassert&gt; template &lt;class T&gt; boost::iterator_range&lt;boost::counting_iterator&lt;T&gt; &gt; xrange(T to) { //these assertions are somewhat problematic: //might produce warnings, if T is unsigned assert(T() &lt;= to); return boost::make_iterator_range(boost::counting_iterator&lt;T&gt;(0), boost::counting_iterator&lt;T&gt;(to)); } template &lt;class T&gt; boost::iterator_range&lt;boost::counting_iterator&lt;T&gt; &gt; xrange(T from, T to) { assert(from &lt;= to); return boost::make_iterator_range(boost::counting_iterator&lt;T&gt;(from), boost::counting_iterator&lt;T&gt;(to)); } //iterator that can do increments in steps (positive and negative) template &lt;class T&gt; class xrange_iterator: public boost::iterator_facade&lt;xrange_iterator&lt;T&gt;, const T, std::forward_iterator_tag&gt; { T value, incr; public: xrange_iterator(T value, T incr = T()): value(value), incr(incr) {} private: friend class boost::iterator_core_access; void increment() { value += incr; } bool equal(const xrange_iterator&amp; other) const { //this is probably somewhat problematic, assuming that the "end iterator" //is always the right-hand value? return (incr &gt;= 0 &amp;&amp; value &gt;= other.value) || (incr &lt; 0 &amp;&amp; value &lt;= other.value); } const T&amp; dereference() const { return value; } }; template &lt;class T&gt; boost::iterator_range&lt;xrange_iterator&lt;T&gt; &gt; xrange(T from, T to, T increment) { assert((increment &gt;= T() &amp;&amp; from &lt;= to) || (increment &lt; T() &amp;&amp; from &gt;= to)); return boost::make_iterator_range(xrange_iterator&lt;T&gt;(from, increment), xrange_iterator&lt;T&gt;(to)); } int main() { BOOST_FOREACH(int i, xrange(10)) { std::cout &lt;&lt; i &lt;&lt; ' '; } BOOST_FOREACH(int i, xrange(10, 20)) { std::cout &lt;&lt; i &lt;&lt; ' '; } std::cout &lt;&lt; '\n'; BOOST_FOREACH(int i, xrange(0, 46, 5)) { std::cout &lt;&lt; i &lt;&lt; ' '; } BOOST_FOREACH(int i, xrange(10, 0, -1)) { std::cout &lt;&lt; i &lt;&lt; ' '; } } </code></pre> <p>As others are saying, I don't see this buying you much over a normal for loop.</p>
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