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    <p>As far as I know, there is no such class in C++11.</p> <p>Anyway, I tried to improve your implementation. I made it <em>non-template</em>, as I don't see any <em>advantage</em> in making it <em>template</em>. On the contrary, it has one major disadvantage : that you cannot create the range at runtime, as you need to know the template arguments at compile time itself.</p> <pre><code>//your version auto x = range&lt;m,n&gt;(); //m and n must be known at compile time //my version auto x = range(m,n); //m and n may be known at runtime as well! </code></pre> <p>Here is the code:</p> <pre><code>class range { public: class iterator { friend class range; public: long int operator *() const { return i_; } const iterator &amp;operator ++() { ++i_; return *this; } iterator operator ++(int) { iterator copy(*this); ++i_; return copy; } bool operator ==(const iterator &amp;other) const { return i_ == other.i_; } bool operator !=(const iterator &amp;other) const { return i_ != other.i_; } protected: iterator(long int start) : i_ (start) { } private: unsigned long i_; }; iterator begin() const { return begin_; } iterator end() const { return end_; } range(long int begin, long int end) : begin_(begin), end_(end) {} private: iterator begin_; iterator end_; }; </code></pre> <p>Test code:</p> <pre><code>int main() { int m, n; std::istringstream in("10 20"); if ( in &gt;&gt; m &gt;&gt; n ) //using in, because std::cin cannot be used at coliru. { if ( m &gt; n ) std::swap(m,n); for (auto i : range(m,n)) { std::cout &lt;&lt; i &lt;&lt; " "; } } else std::cout &lt;&lt;"invalid input"; } </code></pre> <p>Output:</p> <p>10 11 12 13 14 15 16 17 18 19</p> <p><a href="http://coliru.stacked-crooked.com/a/2cacfb322d263500" rel="noreferrer">Onine demo</a>.</p>
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    1. POIs there a range class in C++11 for use with range based for loops?
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    1. USNawaz
    1. USNawaz
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    1. COI like it. I thought about a non-template version. And I suppose a good compiler would optimize it well in the case when the values actually are constant. I'll have to test that out.
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      1. USOmnifarious
    2. CO@Nawaz: I'd still template it, on the integral type :) I'd also propose to alias `iterator` to `const_iterator`, have `iterator` derive from `std::iterator` and have `range` implement `cbegin` and `cend`. Oh and... why does `iterator::operator++` returns a *const* reference ?
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      1. USMatthieu M.
    3. CO+1, nice solution; however, you should have retain the `for` loop version of the OP only in your test code also. :)
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      1. USiammilind
 

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