87 lines · cpp
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-exception6//7//===----------------------------------------------------------------------===//8 9// <tuple>10 11// template <class... Types> class tuple;12 13// template <size_t I, class... Types>14// typename tuple_element<I, tuple<Types...> >::type&15// get(tuple<Types...>& t);16 17// UNSUPPORTED: c++0318 19#include <tuple>20#include <string>21#include <cassert>22 23#include "test_macros.h"24 25#if TEST_STD_VER > 1126 27struct Empty {};28 29struct S {30 std::tuple<int, Empty> a;31 int k;32 Empty e;33 constexpr S() : a{1,Empty{}}, k(std::get<0>(a)), e(std::get<1>(a)) {}34 };35 36constexpr std::tuple<int, int> getP () { return { 3, 4 }; }37#endif38 39int main(int, char**)40{41 {42 typedef std::tuple<int> T;43 T t(3);44 assert(std::get<0>(t) == 3);45 std::get<0>(t) = 2;46 assert(std::get<0>(t) == 2);47 }48 {49 typedef std::tuple<std::string, int> T;50 T t("high", 5);51 assert(std::get<0>(t) == "high");52 assert(std::get<1>(t) == 5);53 std::get<0>(t) = "four";54 std::get<1>(t) = 4;55 assert(std::get<0>(t) == "four");56 assert(std::get<1>(t) == 4);57 }58 {59 typedef std::tuple<double&, std::string, int> T;60 double d = 1.5;61 T t(d, "high", 5);62 assert(std::get<0>(t) == 1.5);63 assert(std::get<1>(t) == "high");64 assert(std::get<2>(t) == 5);65 std::get<0>(t) = 2.5;66 std::get<1>(t) = "four";67 std::get<2>(t) = 4;68 assert(std::get<0>(t) == 2.5);69 assert(std::get<1>(t) == "four");70 assert(std::get<2>(t) == 4);71 assert(d == 2.5);72 }73#if TEST_STD_VER > 1174 { // get on an rvalue tuple75 static_assert ( std::get<0> ( std::make_tuple ( 0.0f, 1, 2.0, 3L )) == 0, "" );76 static_assert ( std::get<1> ( std::make_tuple ( 0.0f, 1, 2.0, 3L )) == 1, "" );77 static_assert ( std::get<2> ( std::make_tuple ( 0.0f, 1, 2.0, 3L )) == 2, "" );78 static_assert ( std::get<3> ( std::make_tuple ( 0.0f, 1, 2.0, 3L )) == 3, "" );79 static_assert(S().k == 1, "");80 static_assert(std::get<1>(getP()) == 4, "");81 }82#endif83 84 85 return 0;86}87