concat.cpp 3.3 KB

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  1. // Range v3 library
  2. //
  3. // Copyright Eric Niebler 2014-present
  4. //
  5. // Use, modification and distribution is subject to the
  6. // Boost Software License, Version 1.0. (See accompanying
  7. // file LICENSE_1_0.txt or copy at
  8. // http://www.boost.org/LICENSE_1_0.txt)
  9. //
  10. // Project home: https://github.com/ericniebler/range-v3
  11. #include <array>
  12. #include <vector>
  13. #include <range/v3/core.hpp>
  14. #include <range/v3/view/concat.hpp>
  15. #include <range/v3/view/generate.hpp>
  16. #include <range/v3/view/reverse.hpp>
  17. #include <range/v3/view/remove_if.hpp>
  18. #include <range/v3/view/take_while.hpp>
  19. #include <range/v3/algorithm/equal.hpp>
  20. #include <range/v3/utility/copy.hpp>
  21. #include "../simple_test.hpp"
  22. #include "../test_utils.hpp"
  23. int main()
  24. {
  25. using namespace ranges;
  26. std::vector<std::string> his_face{"this", "is", "his", "face"};
  27. std::vector<std::string> another_mess{"another", "fine", "mess"};
  28. auto joined = views::concat(his_face, another_mess);
  29. CPP_assert(view_<decltype(joined)>);
  30. CPP_assert(random_access_range<decltype(joined)>);
  31. static_assert(std::is_same<range_reference_t<decltype(joined)>, std::string &>::value, "");
  32. CHECK(joined.size() == 7u);
  33. CHECK((joined.end() - joined.begin()) == 7);
  34. ::check_equal(joined | views::reverse, {"mess", "fine", "another", "face", "his", "is", "this"});
  35. auto revjoin = joined | views::reverse;
  36. CHECK((revjoin.end() - revjoin.begin()) == 7);
  37. auto first = joined.begin();
  38. CHECK(*(first+0) == "this");
  39. CHECK(*(first+1) == "is");
  40. CHECK(*(first+2) == "his");
  41. CHECK(*(first+3) == "face");
  42. CHECK(*(first+4) == "another");
  43. CHECK(*(first+5) == "fine");
  44. CHECK(*(first+6) == "mess");
  45. CHECK(*(first) == "this");
  46. CHECK(*(first+=1) == "is");
  47. CHECK(*(first+=1) == "his");
  48. CHECK(*(first+=1) == "face");
  49. CHECK(*(first+=1) == "another");
  50. CHECK(*(first+=1) == "fine");
  51. CHECK(*(first+=1) == "mess");
  52. auto last = joined.end();
  53. CHECK(*(last-1) == "mess");
  54. CHECK(*(last-2) == "fine");
  55. CHECK(*(last-3) == "another");
  56. CHECK(*(last-4) == "face");
  57. CHECK(*(last-5) == "his");
  58. CHECK(*(last-6) == "is");
  59. CHECK(*(last-7) == "this");
  60. CHECK(*(last-=1) == "mess");
  61. CHECK(*(last-=1) == "fine");
  62. CHECK(*(last-=1) == "another");
  63. CHECK(*(last-=1) == "face");
  64. CHECK(*(last-=1) == "his");
  65. CHECK(*(last-=1) == "is");
  66. CHECK(*(last-=1) == "this");
  67. {
  68. const std::array<int, 3> a{{0, 1, 2}};
  69. const std::array<int, 2> b{{3, 4}};
  70. check_equal(views::concat(a, b), {0, 1, 2, 3, 4});
  71. auto odd = [](int i) { return i % 2 != 0; };
  72. auto even_filter = ranges::views::remove_if(odd);
  73. auto f_rng0 = a | even_filter;
  74. auto f_rng1 = b | even_filter;
  75. check_equal(views::concat(f_rng0, f_rng1), {0, 2, 4});
  76. }
  77. // Regression test for http://github.com/ericniebler/range-v3/issues/395.
  78. {
  79. int i = 0;
  80. auto rng = ranges::views::concat(ranges::views::generate([&]{ return i++; }))
  81. | ranges::views::take_while([](int j){ return j < 30; });
  82. CHECK(ranges::distance(ranges::begin(rng), ranges::end(rng)) == 30);
  83. }
  84. {
  85. int const rgi[] = {0,1,2,3};
  86. auto dv = [&]{ return debug_input_view<int const>{rgi}; };
  87. auto rng = views::concat(dv(), dv(), dv());
  88. ::check_equal(rng, {0,1,2,3,0,1,2,3,0,1,2,3});
  89. }
  90. return test_result();
  91. }