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 // UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
10
11 // constexpr explicit zip_view(Views...)
12
13 #include <ranges>
14 #include <tuple>
15
16 #include "types.h"
17
18 template <class T>
19 void conversion_test(T);
20
21 template <class T, class... Args>
22 concept implicitly_constructible_from = requires(Args&&... args) { conversion_test<T>({std::move(args)...}); };
23
24 // test constructor is explicit
25 static_assert(std::constructible_from<std::ranges::zip_view<SimpleCommon>, SimpleCommon>);
26 static_assert(!implicitly_constructible_from<std::ranges::zip_view<SimpleCommon>, SimpleCommon>);
27
28 static_assert(std::constructible_from<std::ranges::zip_view<SimpleCommon, SimpleCommon>, SimpleCommon, SimpleCommon>);
29 static_assert(
30 !implicitly_constructible_from<std::ranges::zip_view<SimpleCommon, SimpleCommon>, SimpleCommon, SimpleCommon>);
31
32 struct MoveAwareView : std::ranges::view_base {
33 int moves = 0;
34 constexpr MoveAwareView() = default;
MoveAwareViewMoveAwareView35 constexpr MoveAwareView(MoveAwareView&& other) : moves(other.moves + 1) { other.moves = 1; }
operator =MoveAwareView36 constexpr MoveAwareView& operator=(MoveAwareView&& other) {
37 moves = other.moves + 1;
38 other.moves = 0;
39 return *this;
40 }
beginMoveAwareView41 constexpr const int* begin() const { return &moves; }
endMoveAwareView42 constexpr const int* end() const { return &moves + 1; }
43 };
44
45 template <class View1, class View2>
constructorTest(auto && buffer1,auto && buffer2)46 constexpr void constructorTest(auto&& buffer1, auto&& buffer2) {
47 std::ranges::zip_view v{View1{buffer1}, View2{buffer2}};
48 auto [i, j] = *v.begin();
49 assert(i == buffer1[0]);
50 assert(j == buffer2[0]);
51 };
52
test()53 constexpr bool test() {
54
55 int buffer[8] = {1, 2, 3, 4, 5, 6, 7, 8};
56 int buffer2[4] = {9, 8, 7, 6};
57
58 {
59 // constructor from views
60 std::ranges::zip_view v(SizedRandomAccessView{buffer}, std::views::iota(0), std::ranges::single_view(2.));
61 auto [i, j, k] = *v.begin();
62 assert(i == 1);
63 assert(j == 0);
64 assert(k == 2.0);
65 }
66
67 {
68 // arguments are moved once
69 MoveAwareView mv;
70 std::ranges::zip_view v{std::move(mv), MoveAwareView{}};
71 auto [numMoves1, numMoves2] = *v.begin();
72 assert(numMoves1 == 2); // one move from the local variable to parameter, one move from parameter to member
73 assert(numMoves2 == 1);
74 }
75
76 // input and forward
77 {
78 constructorTest<InputCommonView, ForwardSizedView>(buffer, buffer2);
79 }
80
81 // bidi and random_access
82 {
83 constructorTest<BidiCommonView, SizedRandomAccessView>(buffer, buffer2);
84 }
85
86 // contiguous
87 {
88 constructorTest<ContiguousCommonView, ContiguousCommonView>(buffer, buffer2);
89 }
90
91 return true;
92 }
93
main(int,char **)94 int main(int, char**) {
95 test();
96 static_assert(test());
97
98 return 0;
99 }
100