xref: /llvm-project/libcxx/test/std/ranges/range.adaptors/range.elements/iterator/ctor.base.pass.cpp (revision 94461822c75d5080bf648f86552f7a59b76905c9)
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 
11 // constexpr explicit iterator(iterator_t<Base> current);
12 
13 #include <cassert>
14 #include <ranges>
15 #include <tuple>
16 
17 #include "../types.h"
18 
19 // Test explicit
20 using BaseIter     = std::tuple<int>*;
21 using ElementsIter = std::ranges::iterator_t<std::ranges::elements_view<std::ranges::subrange<BaseIter, BaseIter>, 0>>;
22 
23 static_assert(std::is_constructible_v<ElementsIter, BaseIter>);
24 static_assert(!std::is_convertible_v<BaseIter, ElementsIter>);
25 
26 struct TracedMoveIter : IterBase<TracedMoveIter>{
27   bool moved = false;
28 
29   constexpr TracedMoveIter()                      = default;
30   constexpr TracedMoveIter(const TracedMoveIter&) = default;
TracedMoveIterTracedMoveIter31   constexpr TracedMoveIter(TracedMoveIter&&) : moved{true} {}
32   constexpr TracedMoveIter& operator=(TracedMoveIter&&)      = default;
33   constexpr TracedMoveIter& operator=(const TracedMoveIter&) = default;
34 };
35 
36 struct TracedMoveView : std::ranges::view_base {
37   TracedMoveIter begin() const;
38   TracedMoveIter end() const;
39 };
40 
test()41 constexpr bool test() {
42   using Iter = std::ranges::iterator_t<std::ranges::elements_view<TracedMoveView, 0>>;
43   Iter iter{TracedMoveIter{}};
44   assert(iter.base().moved);
45 
46   return true;
47 }
48 
main(int,char **)49 int main(int, char**) {
50   test();
51   static_assert(test());
52 
53   return 0;
54 }
55