minus.pass.cpp (2302B)
1 //===----------------------------------------------------------------------===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is dual licensed under the MIT and the University of Illinois Open 6 // Source Licenses. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 // UNSUPPORTED: c++98, c++03, c++11, c++14, c++17 10 11 // <chrono> 12 // class weekday; 13 14 // constexpr weekday operator-(const weekday& x, const days& y) noexcept; 15 // Returns: x + -y. 16 // 17 // constexpr days operator-(const weekday& x, const weekday& y) noexcept; 18 // Returns: If x.ok() == true and y.ok() == true, returns a value d in the range 19 // [days{0}, days{6}] satisfying y + d == x. 20 // Otherwise the value returned is unspecified. 21 // [Example: Sunday - Monday == days{6}. —end example] 22 23 24 extern "C" int printf(const char *, ...); 25 26 #include <chrono> 27 #include <type_traits> 28 #include <cassert> 29 30 #include "test_macros.h" 31 #include "../../euclidian.h" 32 33 template <typename WD, typename Ds> 34 constexpr bool testConstexpr() 35 { 36 { 37 WD wd{5}; 38 Ds offset{3}; 39 if (wd - offset != WD{2}) return false; 40 if (wd - WD{2} != offset) return false; 41 } 42 43 // Check the example 44 if (WD{0} - WD{1} != Ds{6}) return false; 45 return true; 46 } 47 48 int main() 49 { 50 using weekday = std::chrono::weekday; 51 using days = std::chrono::days; 52 53 ASSERT_NOEXCEPT( std::declval<weekday>() - std::declval<days>()); 54 ASSERT_SAME_TYPE(weekday, decltype(std::declval<weekday>() - std::declval<days>())); 55 56 ASSERT_NOEXCEPT( std::declval<weekday>() - std::declval<weekday>()); 57 ASSERT_SAME_TYPE(days, decltype(std::declval<weekday>() - std::declval<weekday>())); 58 59 static_assert(testConstexpr<weekday, days>(), ""); 60 61 for (unsigned i = 0; i <= 6; ++i) 62 for (unsigned j = 0; j <= 6; ++j) 63 { 64 weekday wd = weekday{i} - days{j}; 65 assert(wd + days{j} == weekday{i}); 66 assert((static_cast<unsigned>(wd) == euclidian_subtraction<unsigned, 0, 6>(i, j))); 67 } 68 69 for (unsigned i = 0; i <= 6; ++i) 70 for (unsigned j = 0; j <= 6; ++j) 71 { 72 days d = weekday{j} - weekday{i}; 73 assert(weekday{i} + d == weekday{j}); 74 } 75 76 }