weekday.h 6.7 KB

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172
  1. // -*- C++ -*-
  2. //===----------------------------------------------------------------------===//
  3. //
  4. // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
  5. // See https://llvm.org/LICENSE.txt for license information.
  6. // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
  7. //
  8. //===----------------------------------------------------------------------===//
  9. #ifndef _LIBCPP___CHRONO_WEEKDAY_H
  10. #define _LIBCPP___CHRONO_WEEKDAY_H
  11. #include <__chrono/calendar.h>
  12. #include <__chrono/duration.h>
  13. #include <__chrono/system_clock.h>
  14. #include <__chrono/time_point.h>
  15. #include <__config>
  16. #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
  17. # pragma GCC system_header
  18. #endif
  19. #if _LIBCPP_STD_VER >= 20
  20. _LIBCPP_BEGIN_NAMESPACE_STD
  21. namespace chrono
  22. {
  23. class weekday_indexed;
  24. class weekday_last;
  25. class weekday {
  26. private:
  27. unsigned char __wd_;
  28. _LIBCPP_HIDE_FROM_ABI static constexpr unsigned char __weekday_from_days(int __days) noexcept;
  29. public:
  30. weekday() = default;
  31. _LIBCPP_HIDE_FROM_ABI inline explicit constexpr weekday(unsigned __val) noexcept : __wd_(static_cast<unsigned char>(__val == 7 ? 0 : __val)) {}
  32. _LIBCPP_HIDE_FROM_ABI inline constexpr weekday(const sys_days& __sysd) noexcept
  33. : __wd_(__weekday_from_days(__sysd.time_since_epoch().count())) {}
  34. _LIBCPP_HIDE_FROM_ABI inline explicit constexpr weekday(const local_days& __locd) noexcept
  35. : __wd_(__weekday_from_days(__locd.time_since_epoch().count())) {}
  36. _LIBCPP_HIDE_FROM_ABI inline constexpr weekday& operator++() noexcept { __wd_ = (__wd_ == 6 ? 0 : __wd_ + 1); return *this; }
  37. _LIBCPP_HIDE_FROM_ABI inline constexpr weekday operator++(int) noexcept { weekday __tmp = *this; ++(*this); return __tmp; }
  38. _LIBCPP_HIDE_FROM_ABI inline constexpr weekday& operator--() noexcept { __wd_ = (__wd_ == 0 ? 6 : __wd_ - 1); return *this; }
  39. _LIBCPP_HIDE_FROM_ABI inline constexpr weekday operator--(int) noexcept { weekday __tmp = *this; --(*this); return __tmp; }
  40. _LIBCPP_HIDE_FROM_ABI constexpr weekday& operator+=(const days& __dd) noexcept;
  41. _LIBCPP_HIDE_FROM_ABI constexpr weekday& operator-=(const days& __dd) noexcept;
  42. _LIBCPP_HIDE_FROM_ABI inline constexpr unsigned c_encoding() const noexcept { return __wd_; }
  43. _LIBCPP_HIDE_FROM_ABI inline constexpr unsigned iso_encoding() const noexcept { return __wd_ == 0u ? 7 : __wd_; }
  44. _LIBCPP_HIDE_FROM_ABI inline constexpr bool ok() const noexcept { return __wd_ <= 6; }
  45. _LIBCPP_HIDE_FROM_ABI constexpr weekday_indexed operator[](unsigned __index) const noexcept;
  46. _LIBCPP_HIDE_FROM_ABI constexpr weekday_last operator[](last_spec) const noexcept;
  47. };
  48. // https://howardhinnant.github.io/date_algorithms.html#weekday_from_days
  49. _LIBCPP_HIDE_FROM_ABI inline constexpr
  50. unsigned char weekday::__weekday_from_days(int __days) noexcept
  51. {
  52. return static_cast<unsigned char>(
  53. static_cast<unsigned>(__days >= -4 ? (__days+4) % 7 : (__days+5) % 7 + 6)
  54. );
  55. }
  56. _LIBCPP_HIDE_FROM_ABI inline constexpr
  57. bool operator==(const weekday& __lhs, const weekday& __rhs) noexcept
  58. { return __lhs.c_encoding() == __rhs.c_encoding(); }
  59. _LIBCPP_HIDE_FROM_ABI inline constexpr
  60. bool operator< (const weekday& __lhs, const weekday& __rhs) noexcept
  61. { return __lhs.c_encoding() < __rhs.c_encoding(); }
  62. _LIBCPP_HIDE_FROM_ABI inline constexpr
  63. bool operator> (const weekday& __lhs, const weekday& __rhs) noexcept
  64. { return __rhs < __lhs; }
  65. _LIBCPP_HIDE_FROM_ABI inline constexpr
  66. bool operator<=(const weekday& __lhs, const weekday& __rhs) noexcept
  67. { return !(__rhs < __lhs);}
  68. _LIBCPP_HIDE_FROM_ABI inline constexpr
  69. bool operator>=(const weekday& __lhs, const weekday& __rhs) noexcept
  70. { return !(__lhs < __rhs); }
  71. _LIBCPP_HIDE_FROM_ABI constexpr
  72. weekday operator+(const weekday& __lhs, const days& __rhs) noexcept
  73. {
  74. auto const __mu = static_cast<long long>(__lhs.c_encoding()) + __rhs.count();
  75. auto const __yr = (__mu >= 0 ? __mu : __mu - 6) / 7;
  76. return weekday{static_cast<unsigned>(__mu - __yr * 7)};
  77. }
  78. _LIBCPP_HIDE_FROM_ABI constexpr
  79. weekday operator+(const days& __lhs, const weekday& __rhs) noexcept
  80. { return __rhs + __lhs; }
  81. _LIBCPP_HIDE_FROM_ABI constexpr
  82. weekday operator-(const weekday& __lhs, const days& __rhs) noexcept
  83. { return __lhs + -__rhs; }
  84. _LIBCPP_HIDE_FROM_ABI constexpr
  85. days operator-(const weekday& __lhs, const weekday& __rhs) noexcept
  86. {
  87. const int __wdu = __lhs.c_encoding() - __rhs.c_encoding();
  88. const int __wk = (__wdu >= 0 ? __wdu : __wdu-6) / 7;
  89. return days{__wdu - __wk * 7};
  90. }
  91. _LIBCPP_HIDE_FROM_ABI inline constexpr
  92. weekday& weekday::operator+=(const days& __dd) noexcept
  93. { *this = *this + __dd; return *this; }
  94. _LIBCPP_HIDE_FROM_ABI inline constexpr
  95. weekday& weekday::operator-=(const days& __dd) noexcept
  96. { *this = *this - __dd; return *this; }
  97. class weekday_indexed {
  98. private:
  99. chrono::weekday __wd_;
  100. unsigned char __idx_;
  101. public:
  102. weekday_indexed() = default;
  103. _LIBCPP_HIDE_FROM_ABI inline constexpr weekday_indexed(const chrono::weekday& __wdval, unsigned __idxval) noexcept
  104. : __wd_{__wdval}, __idx_(__idxval) {}
  105. _LIBCPP_HIDE_FROM_ABI inline constexpr chrono::weekday weekday() const noexcept { return __wd_; }
  106. _LIBCPP_HIDE_FROM_ABI inline constexpr unsigned index() const noexcept { return __idx_; }
  107. _LIBCPP_HIDE_FROM_ABI inline constexpr bool ok() const noexcept { return __wd_.ok() && __idx_ >= 1 && __idx_ <= 5; }
  108. };
  109. _LIBCPP_HIDE_FROM_ABI inline constexpr
  110. bool operator==(const weekday_indexed& __lhs, const weekday_indexed& __rhs) noexcept
  111. { return __lhs.weekday() == __rhs.weekday() && __lhs.index() == __rhs.index(); }
  112. class weekday_last {
  113. private:
  114. chrono::weekday __wd_;
  115. public:
  116. _LIBCPP_HIDE_FROM_ABI explicit constexpr weekday_last(const chrono::weekday& __val) noexcept
  117. : __wd_{__val} {}
  118. _LIBCPP_HIDE_FROM_ABI constexpr chrono::weekday weekday() const noexcept { return __wd_; }
  119. _LIBCPP_HIDE_FROM_ABI constexpr bool ok() const noexcept { return __wd_.ok(); }
  120. };
  121. _LIBCPP_HIDE_FROM_ABI inline constexpr
  122. bool operator==(const weekday_last& __lhs, const weekday_last& __rhs) noexcept
  123. { return __lhs.weekday() == __rhs.weekday(); }
  124. _LIBCPP_HIDE_FROM_ABI inline constexpr
  125. weekday_indexed weekday::operator[](unsigned __index) const noexcept { return weekday_indexed{*this, __index}; }
  126. _LIBCPP_HIDE_FROM_ABI inline constexpr
  127. weekday_last weekday::operator[](last_spec) const noexcept { return weekday_last{*this}; }
  128. inline constexpr weekday Sunday{0};
  129. inline constexpr weekday Monday{1};
  130. inline constexpr weekday Tuesday{2};
  131. inline constexpr weekday Wednesday{3};
  132. inline constexpr weekday Thursday{4};
  133. inline constexpr weekday Friday{5};
  134. inline constexpr weekday Saturday{6};
  135. } // namespace chrono
  136. _LIBCPP_END_NAMESPACE_STD
  137. #endif // _LIBCPP_STD_VER >= 20
  138. #endif // _LIBCPP___CHRONO_WEEKDAY_H