text: // Boost.Range 2.0 Extension library
  // via PStade Oven Library
  //
  // Copyright Kohei Takahashi 2014.
  // Use, modification and distribution is subject to the Boost Software License,
  // Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
  // http://www.boost.org/LICENSE_1_0.txt)
  
  #include "mock_kv_range.hpp"
  #include <boost/range/adaptor/elements.hpp>
  
  int main(int, const char**)
  {
      using boost::range::unit_test::mock_kv_range;
      using boost::adaptors::elements;
  
      // This next line should fail when Boost.Range concept checking is
      // enabled since the filtered adaptor takes at least a SinglePassRange.
      return (mock_kv_range<boost::incrementable_traversal_tag>() | elements<0>()).front();
  }
  