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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
// take_view() requires default_initializable<V> = default;
#include <ranges>
#include <cassert>
int buff[8] = {1, 2, 3, 4, 5, 6, 7, 8};
struct DefaultConstructible : std::ranges::view_base {
constexpr DefaultConstructible() : begin_(buff), end_(buff + 8) { }
constexpr int const* begin() const { return begin_; }
constexpr int const* end() const { return end_; }
private:
int const* begin_;
int const* end_;
};
struct NonDefaultConstructible : std::ranges::view_base {
NonDefaultConstructible() = delete;
int* begin() const;
int* end() const;
};
constexpr bool test() {
{
std::ranges::take_view<DefaultConstructible> tv;
assert(tv.begin() == buff);
assert(tv.size() == 0);
}
// Test SFINAE-friendliness
{
static_assert( std::is_default_constructible_v<std::ranges::take_view<DefaultConstructible>>);
static_assert(!std::is_default_constructible_v<std::ranges::take_view<NonDefaultConstructible>>);
}
return true;
}
int main(int, char**) {
test();
static_assert(test());
return 0;
}
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