count_if.cpp 1.6 KB

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  1. /*=============================================================================
  2. Copyright (c) 2001-2011 Joel de Guzman
  3. Copyright (c) 2005 Eric Niebler
  4. Distributed under the Boost Software License, Version 1.0. (See accompanying
  5. file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
  6. ==============================================================================*/
  7. #include <boost/detail/lightweight_test.hpp>
  8. #include <boost/fusion/container/vector/vector.hpp>
  9. #include <boost/fusion/adapted/mpl.hpp>
  10. #include <boost/fusion/algorithm/query/count_if.hpp>
  11. #include <boost/mpl/vector_c.hpp>
  12. #include <functional>
  13. template <typename F> struct bind1st;
  14. template <template <typename> class F, typename T>
  15. struct bind1st<F<T> > : public F<T>
  16. {
  17. T n;
  18. bind1st(T n) : n(n) { }
  19. bool operator()(T v) const { return F<T>::operator()(n, v); }
  20. };
  21. int
  22. main()
  23. {
  24. {
  25. boost::fusion::vector<int, short, double> t(1, 2, 3.3);
  26. BOOST_TEST(boost::fusion::count_if(t, bind1st<std::equal_to<double> >(2)) == 1);
  27. }
  28. {
  29. boost::fusion::vector<int, short, double> t(1, 2, 3.3);
  30. BOOST_TEST(boost::fusion::count_if(t, bind1st<std::equal_to<double> >(3)) == 0);
  31. }
  32. {
  33. typedef boost::mpl::vector_c<int, 1, 2, 3> mpl_vec;
  34. // Cannot use lambda here as mpl iterators return rvalues and lambda needs lvalues
  35. BOOST_TEST(boost::fusion::count_if(mpl_vec(), bind1st<std::greater_equal<int> >(2)) == 2);
  36. BOOST_TEST(boost::fusion::count_if(mpl_vec(), bind1st<std::less<int> >(2)) == 1);
  37. }
  38. return boost::report_errors();
  39. }