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
10 // UNSUPPORTED: libcpp-has-no-incomplete-ranges
11
12 // constexpr iterator<false> begin();
13 // constexpr iterator<true> begin() const
14 // requires range<const V> &&
15 // regular_invocable<const F&, range_reference_t<const V>>;
16
17 #include <ranges>
18
19 #include "test_macros.h"
20 #include "types.h"
21
22 template<class T>
23 concept BeginInvocable = requires(T t) { t.begin(); };
24
test()25 constexpr bool test() {
26 int buff[8] = {0, 1, 2, 3, 4, 5, 6, 7};
27
28 {
29 std::ranges::transform_view transformView(MoveOnlyView{buff}, PlusOneMutable{});
30 assert(transformView.begin().base() == buff);
31 assert(*transformView.begin() == 1);
32 }
33
34 {
35 std::ranges::transform_view transformView(ForwardView{buff}, PlusOneMutable{});
36 assert(base(transformView.begin().base()) == buff);
37 assert(*transformView.begin() == 1);
38 }
39
40 {
41 std::ranges::transform_view transformView(InputView{buff}, PlusOneMutable{});
42 assert(base(transformView.begin().base()) == buff);
43 assert(*transformView.begin() == 1);
44 }
45
46 {
47 const std::ranges::transform_view transformView(MoveOnlyView{buff}, PlusOne{});
48 assert(*transformView.begin() == 1);
49 }
50
51 static_assert(!BeginInvocable<const std::ranges::transform_view<MoveOnlyView, PlusOneMutable>>);
52
53 return true;
54 }
55
main(int,char **)56 int main(int, char**) {
57 test();
58 static_assert(test());
59
60 return 0;
61 }
62