1 //===----------------------------------------------------------------------===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 9 // <tuple> 10 11 // template <class... Types> class tuple; 12 13 // template <class... UTypes> 14 // tuple& operator=(const tuple<UTypes...>& u); 15 16 // UNSUPPORTED: c++03 17 18 #include <tuple> 19 #include <string> 20 #include <cassert> 21 22 #include "test_macros.h" 23 24 struct B 25 { 26 int id_; 27 28 explicit B(int i = 0) : id_(i) {} 29 }; 30 31 struct D 32 : B 33 { 34 explicit D(int i = 0) : B(i) {} 35 }; 36 37 struct NonAssignable { 38 NonAssignable& operator=(NonAssignable const&) = delete; 39 NonAssignable& operator=(NonAssignable&&) = delete; 40 }; 41 42 int main(int, char**) 43 { 44 { 45 typedef std::tuple<long> T0; 46 typedef std::tuple<long long> T1; 47 T0 t0(2); 48 T1 t1; 49 t1 = t0; 50 assert(std::get<0>(t1) == 2); 51 } 52 { 53 typedef std::tuple<long, char> T0; 54 typedef std::tuple<long long, int> T1; 55 T0 t0(2, 'a'); 56 T1 t1; 57 t1 = t0; 58 assert(std::get<0>(t1) == 2); 59 assert(std::get<1>(t1) == int('a')); 60 } 61 { 62 typedef std::tuple<long, char, D> T0; 63 typedef std::tuple<long long, int, B> T1; 64 T0 t0(2, 'a', D(3)); 65 T1 t1; 66 t1 = t0; 67 assert(std::get<0>(t1) == 2); 68 assert(std::get<1>(t1) == int('a')); 69 assert(std::get<2>(t1).id_ == 3); 70 } 71 { 72 D d(3); 73 D d2(2); 74 typedef std::tuple<long, char, D&> T0; 75 typedef std::tuple<long long, int, B&> T1; 76 T0 t0(2, 'a', d2); 77 T1 t1(1, 'b', d); 78 t1 = t0; 79 assert(std::get<0>(t1) == 2); 80 assert(std::get<1>(t1) == int('a')); 81 assert(std::get<2>(t1).id_ == 2); 82 } 83 { 84 // Test that tuple evaluates correctly applies an lvalue reference 85 // before evaluating is_assignable (i.e. 'is_assignable<int&, int&>') 86 // instead of evaluating 'is_assignable<int&&, int&>' which is false. 87 int x = 42; 88 int y = 43; 89 std::tuple<int&&> t(std::move(x)); 90 std::tuple<int&> t2(y); 91 t = t2; 92 assert(std::get<0>(t) == 43); 93 assert(&std::get<0>(t) == &x); 94 } 95 { 96 using T = std::tuple<int, NonAssignable>; 97 using U = std::tuple<NonAssignable, int>; 98 static_assert(!std::is_assignable<T, U const&>::value, ""); 99 static_assert(!std::is_assignable<U, T const&>::value, ""); 100 } 101 102 return 0; 103 } 104