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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
//
//===----------------------------------------------------------------------===//
// REQUIRES: std-at-least-c++23
// <ranges>
// join_with_view()
// requires default_initializable<V> && default_initializable<Pattern> = default;
#include <ranges>
#include <algorithm>
#include <array>
#include <cassert>
#include <type_traits>
static constexpr auto view = std::to_array<std::array<int, 2>>({{1, 2}, {3, 4}, {5, 6}});
struct TrivialView : std::ranges::view_base {
int val_; // intentionally uninitialized
constexpr auto begin() { return view.data(); }
constexpr auto end() { return view.data() + view.size(); }
};
static_assert(std::is_trivially_copyable_v<TrivialView> && std::is_trivially_default_constructible_v<TrivialView>);
struct NonDefaultConstructibleView : TrivialView {
NonDefaultConstructibleView(int);
};
struct TrivialPattern : std::ranges::view_base {
int val_; // intentionally uninitialized
constexpr int* begin() { return &val_; }
constexpr int* end() { return &val_ + 1; }
};
static_assert(std::is_trivially_copyable_v<TrivialPattern> &&
std::is_trivially_default_constructible_v<TrivialPattern>);
struct NonDefaultConstructiblePattern : TrivialPattern {
NonDefaultConstructiblePattern(int);
};
constexpr bool test() {
{ // Check if `base_` and `pattern_` are value initialised
std::ranges::join_with_view<TrivialView, TrivialPattern> v;
assert(std::move(v).base().val_ == 0);
assert(std::ranges::equal(v, std::array{1, 2, 0, 3, 4, 0, 5, 6}));
}
{ // Default constructor should not be explicit
[[maybe_unused]] std::ranges::join_with_view<TrivialView, TrivialPattern> v = {};
}
static_assert(std::default_initializable<std::ranges::join_with_view<TrivialView, TrivialPattern>>);
static_assert(!std::default_initializable<std::ranges::join_with_view<TrivialView, NonDefaultConstructiblePattern>>);
static_assert(!std::default_initializable<std::ranges::join_with_view<NonDefaultConstructibleView, TrivialPattern>>);
static_assert(!std::default_initializable<
std::ranges::join_with_view<NonDefaultConstructibleView, NonDefaultConstructiblePattern>>);
return true;
}
int main(int, char**) {
test();
static_assert(test());
return 0;
}
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