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    copied!<p>The solution is this, but with drawback that custom defined iterator classes must have typedefs defined inside the classes and not just specialized std::iterator_traits class.</p> <pre><code>// IsIterator.cpp : Defines the entry point for the console application. // #include "stdafx.h" #include &lt;iterator&gt; #include &lt;iostream&gt; #include &lt;vector&gt; template &lt;typename T&gt; class ExtractType { public: typedef T Result; }; template &lt;typename U&gt; class ExtractType&lt;std::iterator_traits&lt;U&gt; &gt; { public: typedef U Result; }; template &lt;typename T&gt; class IsIteratorPointer { public: static const bool value = false; }; template &lt;typename T&gt; class IsIteratorPointer&lt;T*&gt; { public: static const bool value = true; }; template &lt;typename T&gt; class IsIteratorPointer&lt;const T*&gt; { public: static const bool value = true; }; template &lt;typename T&gt; class IsIterator { public: struct TrueValue { char val; }; struct FalseValue { char val[2]; }; template &lt;typename U&gt; static TrueValue evaluateIsIter(typename U::iterator_category*); template &lt;typename U&gt; static FalseValue evaluateIsIter(...); typedef typename ExtractType&lt;T&gt;::Result TestType; static const bool value = IsIteratorPointer&lt;TestType&gt;::value || sizeof(evaluateIsIter&lt;TestType&gt;(0)) == sizeof(TrueValue); }; struct Foo { }; template &lt;&gt; struct std::iterator_traits&lt;Foo&gt; { typedef random_access_iterator_tag iterator_category; }; int _tmain(int argc, _TCHAR* argv[]) { std::cout &lt;&lt; IsIterator&lt; int &gt;::value &lt;&lt; std::endl; std::cout &lt;&lt; IsIterator&lt; std::iterator_traits&lt;int&gt; &gt;::value &lt;&lt; std::endl; std::cout &lt;&lt; IsIterator&lt; std::iterator_traits&lt;int*&gt; &gt;::value &lt;&lt; std::endl; std::cout &lt;&lt; IsIterator&lt; std::iterator_traits&lt;Foo&gt; &gt;::value &lt;&lt; std::endl; // Will be 0 (only drawback) - typedef must be in Foo directly std::cout &lt;&lt; IsIterator&lt; std::vector&lt;int&gt;::const_iterator &gt;::value &lt;&lt; std::endl; return 0; } </code></pre> <p>The question now remains: Can this drawback somehow be removed?</p>
 

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