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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
// transform_view() requires std::default_initializable<V> &&
// std::default_initializable<F> = default;
#include <ranges>
#include <cassert>
#include <type_traits>
constexpr int buff[] = {1, 2, 3};
struct DefaultConstructibleView : std::ranges::view_base {
constexpr DefaultConstructibleView() : begin_(buff), end_(buff + 3) { }
constexpr int const* begin() const { return begin_; }
constexpr int const* end() const { return end_; }
private:
int const* begin_;
int const* end_;
};
struct DefaultConstructibleFunction {
int state_;
constexpr DefaultConstructibleFunction() : state_(100) { }
constexpr int operator()(int i) const { return i + state_; }
};
struct NoDefaultCtrView : std::ranges::view_base {
NoDefaultCtrView() = delete;
int* begin() const;
int* end() const;
};
struct NoDefaultFunction {
NoDefaultFunction() = delete;
constexpr int operator()(int i) const;
};
constexpr bool test() {
{
std::ranges::transform_view<DefaultConstructibleView, DefaultConstructibleFunction> view;
assert(view.size() == 3);
assert(view[0] == 101);
assert(view[1] == 102);
assert(view[2] == 103);
}
{
std::ranges::transform_view<DefaultConstructibleView, DefaultConstructibleFunction> view = {};
assert(view.size() == 3);
assert(view[0] == 101);
assert(view[1] == 102);
assert(view[2] == 103);
}
static_assert(!std::is_default_constructible_v<std::ranges::transform_view<NoDefaultCtrView, DefaultConstructibleFunction>>);
static_assert(!std::is_default_constructible_v<std::ranges::transform_view<DefaultConstructibleView, NoDefaultFunction>>);
static_assert(!std::is_default_constructible_v<std::ranges::transform_view<NoDefaultCtrView, NoDefaultFunction>>);
return true;
}
int main(int, char**) {
test();
static_assert(test());
return 0;
}
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