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 // <array> 10 // UNSUPPORTED: c++03, c++11, c++14 11 12 // template <class T, class... U> 13 // array(T, U...) -> array<T, 1 + sizeof...(U)>; 14 // 15 // Requires: (is_same_v<T, U> && ...) is true. Otherwise the program is ill-formed. 16 17 #include <array> 18 #include <cassert> 19 #include <cstddef> 20 21 // std::array is explicitly allowed to be initialized with A a = { init-list };. 22 // Disable the missing braces warning for this reason. 23 #include "disable_missing_braces_warning.h" 24 25 #include "test_macros.h" 26 27 constexpr bool tests() 28 { 29 // Test the explicit deduction guides 30 { 31 std::array arr{1,2,3}; // array(T, U...) 32 static_assert(std::is_same_v<decltype(arr), std::array<int, 3>>, ""); 33 assert(arr[0] == 1); 34 assert(arr[1] == 2); 35 assert(arr[2] == 3); 36 } 37 38 { 39 const long l1 = 42; 40 std::array arr{1L, 4L, 9L, l1}; // array(T, U...) 41 static_assert(std::is_same_v<decltype(arr)::value_type, long>, ""); 42 static_assert(arr.size() == 4, ""); 43 assert(arr[0] == 1); 44 assert(arr[1] == 4); 45 assert(arr[2] == 9); 46 assert(arr[3] == l1); 47 } 48 49 // Test the implicit deduction guides 50 { 51 std::array<double, 2> source = {4.0, 5.0}; 52 std::array arr(source); // array(array) 53 static_assert(std::is_same_v<decltype(arr), decltype(source)>, ""); 54 static_assert(std::is_same_v<decltype(arr), std::array<double, 2>>, ""); 55 assert(arr[0] == 4.0); 56 assert(arr[1] == 5.0); 57 } 58 59 return true; 60 } 61 62 int main(int, char**) 63 { 64 tests(); 65 static_assert(tests(), ""); 66 return 0; 67 } 68