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//===----------------------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
// UNSUPPORTED: c++03, c++11, c++14, c++17
// constexpr drop_while_view(V base, Pred pred); // explicit since C++23
#include <cassert>
#include <ranges>
#include <type_traits>
#include <utility>
#include "MoveOnly.h"
#include "test_convertible.h"
#include "test_macros.h"
struct View : std::ranges::view_base {
MoveOnly mo;
int* begin() const;
int* end() const;
};
struct Pred {
bool copied = false;
bool moved = false;
constexpr Pred() = default;
constexpr Pred(Pred&&) : moved(true) {}
constexpr Pred(const Pred&) : copied(true) {}
bool operator()(int) const;
};
// SFINAE tests.
#if TEST_STD_VER >= 23
static_assert(!test_convertible<std::ranges::drop_while_view<View, Pred>, View, Pred>(),
"This constructor must be explicit");
#else
static_assert( test_convertible<std::ranges::drop_while_view<View, Pred>, View, Pred>(),
"This constructor must not be explicit");
#endif // TEST_STD_VER >= 23
constexpr bool test() {
{
std::ranges::drop_while_view<View, Pred> dwv{View{{}, MoveOnly{5}}, Pred{}};
assert(dwv.pred().moved);
assert(!dwv.pred().copied);
assert(std::move(dwv).base().mo.get() == 5);
}
return true;
}
int main(int, char**) {
test();
static_assert(test());
return 0;
}
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