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
20using BaseIter = std::tuple<int>*;
21using ElementsIter = std::ranges::iterator_t<std::ranges::elements_view<std::ranges::subrange<BaseIter, BaseIter>, 0>>;
22
23static_assert(std::is_constructible_v<ElementsIter, BaseIter>);
24static_assert(!std::is_convertible_v<BaseIter, ElementsIter>);
25
26struct TracedMoveIter : IterBase<TracedMoveIter>{
27 bool moved = false;
28
29 constexpr TracedMoveIter() = default;
30 constexpr TracedMoveIter(const TracedMoveIter&) = default;
31 constexpr TracedMoveIter(TracedMoveIter&&) : moved{true} {}
32 constexpr TracedMoveIter& operator=(TracedMoveIter&&) = default;
33 constexpr TracedMoveIter& operator=(const TracedMoveIter&) = default;
34};
35
36struct TracedMoveView : std::ranges::view_base {
37 TracedMoveIter begin() const;
38 TracedMoveIter end() const;
39};
40
41constexpr 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
49int main(int, char**) {
50 test();
51 static_assert(test());
52
53 return 0;
54}
55

source code of libcxx/test/std/ranges/range.adaptors/range.elements/iterator/ctor.base.pass.cpp