variant_in_place_index_construct.cpp 3.4 KB

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138
  1. // Copyright 2017 Peter Dimov.
  2. //
  3. // Distributed under the Boost Software License, Version 1.0.
  4. //
  5. // See accompanying file LICENSE_1_0.txt or copy at
  6. // http://www.boost.org/LICENSE_1_0.txt
  7. #include <boost/variant2/variant.hpp>
  8. #include <boost/core/lightweight_test.hpp>
  9. #include <boost/core/lightweight_test_trait.hpp>
  10. #include <type_traits>
  11. #include <utility>
  12. #include <string>
  13. using namespace boost::variant2;
  14. struct X
  15. {
  16. X() = default;
  17. X( in_place_index_t<0> ) = delete;
  18. };
  19. int main()
  20. {
  21. {
  22. variant<int> v( in_place_index_t<0>{} );
  23. BOOST_TEST_EQ( v.index(), 0 );
  24. BOOST_TEST_EQ( get<0>(v), 0 );
  25. }
  26. {
  27. variant<X> v( in_place_index_t<0>{} );
  28. BOOST_TEST_EQ( v.index(), 0 );
  29. }
  30. {
  31. variant<int> v( in_place_index_t<0>{}, 1 );
  32. BOOST_TEST_EQ( v.index(), 0 );
  33. BOOST_TEST_EQ( get<0>(v), 1 );
  34. }
  35. {
  36. variant<int, float> v( in_place_index_t<0>{} );
  37. BOOST_TEST_EQ( v.index(), 0 );
  38. BOOST_TEST_EQ( get<0>(v), 0 );
  39. }
  40. {
  41. variant<int, float> v( in_place_index_t<0>{}, 1 );
  42. BOOST_TEST_EQ( v.index(), 0 );
  43. BOOST_TEST_EQ( get<0>(v), 1 );
  44. }
  45. {
  46. variant<int, float> v( in_place_index_t<1>{} );
  47. BOOST_TEST_EQ( v.index(), 1 );
  48. BOOST_TEST_EQ( get<1>(v), 0 );
  49. }
  50. {
  51. variant<int, float> v( in_place_index_t<1>{}, 3.14f );
  52. BOOST_TEST_EQ( v.index(), 1 );
  53. BOOST_TEST_EQ( get<1>(v), 3.14f );
  54. }
  55. {
  56. variant<int, int, float, float, std::string, std::string> v( in_place_index_t<0>{}, 1 );
  57. BOOST_TEST_EQ( v.index(), 0 );
  58. BOOST_TEST_EQ( get<0>(v), 1 );
  59. }
  60. {
  61. variant<int, int, float, float, std::string, std::string> v( in_place_index_t<1>{}, 1 );
  62. BOOST_TEST_EQ( v.index(), 1 );
  63. BOOST_TEST_EQ( get<1>(v), 1 );
  64. }
  65. {
  66. variant<int, int, float, float, std::string, std::string> v( in_place_index_t<2>{}, 3.14f );
  67. BOOST_TEST_EQ( v.index(), 2 );
  68. BOOST_TEST_EQ( get<2>(v), 3.14f );
  69. }
  70. {
  71. variant<int, int, float, float, std::string, std::string> v( in_place_index_t<3>{}, 3.14f );
  72. BOOST_TEST_EQ( v.index(), 3 );
  73. BOOST_TEST_EQ( get<3>(v), 3.14f );
  74. }
  75. {
  76. variant<int, int, float, float, std::string, std::string> v( in_place_index_t<4>{}, "text" );
  77. BOOST_TEST_EQ( v.index(), 4 );
  78. BOOST_TEST_EQ( get<4>(v), std::string("text") );
  79. }
  80. {
  81. variant<int, int, float, float, std::string, std::string> v( in_place_index_t<5>{}, "text" );
  82. BOOST_TEST_EQ( v.index(), 5 );
  83. BOOST_TEST_EQ( get<5>(v), std::string("text") );
  84. }
  85. {
  86. variant<int, int, float, float, std::string, std::string> v( in_place_index_t<5>{}, 4, 'a' );
  87. BOOST_TEST_EQ( v.index(), 5 );
  88. BOOST_TEST_EQ( get<5>(v), std::string( 4, 'a' ) );
  89. }
  90. {
  91. variant<int, int, float, float, std::string, std::string> v( in_place_index_t<4>{}, { 'a', 'b', 'c' } );
  92. BOOST_TEST_EQ( v.index(), 4 );
  93. BOOST_TEST_EQ( get<4>(v), (std::string{ 'a', 'b', 'c' }) );
  94. }
  95. {
  96. variant<int, int, float, float, std::string, std::string> v( in_place_index_t<5>{}, { 'a', 'b', 'c' }, std::allocator<char>() );
  97. BOOST_TEST_EQ( v.index(), 5 );
  98. BOOST_TEST_EQ( get<5>(v), (std::string{ 'a', 'b', 'c' }) );
  99. }
  100. return boost::report_errors();
  101. }