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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 bool empty() const;
#include <cassert>
#include <concepts>
#include <ranges>
#include <utility>
#include <vector>
#include "types.h"
template <typename R>
concept HasEmpty = requires(const R r) {
std::ranges::empty(r);
{ r.empty() } -> std::same_as<bool>;
};
constexpr void test_empty_iota_sfinae() {
std::vector<int> ev;
auto iv = std::views::iota(std::ranges::begin(ev), std::ranges::end(ev));
static_assert(HasEmpty<decltype(iv)>);
static_assert(HasEmpty<decltype(std::as_const(iv))>);
}
constexpr void test_nonempty_iota_sfinae() {
// Default ctr
{
std::ranges::iota_view<Int42<DefaultTo42>> iv;
static_assert(HasEmpty<decltype(iv)>);
}
// Value pass
{
std::ranges::iota_view<SomeInt> iv(SomeInt(94));
static_assert(HasEmpty<decltype(iv)>);
}
{
std::vector<char> v;
auto it = std::back_inserter(v);
auto iv = std::views::iota(it);
static_assert(HasEmpty<decltype(iv)>);
}
{
std::vector<char> v{'b', 'a', 'b', 'a', 'z', 'm', 't'};
auto it = std::back_inserter(v);
auto iv = std::views::iota(it);
static_assert(HasEmpty<decltype(iv)>);
}
}
constexpr void test_empty_iota() {
std::vector<int> ev;
auto iv = std::views::iota(std::ranges::begin(ev), std::ranges::end(ev));
assert(iv.empty());
assert(std::as_const(iv).empty());
}
constexpr void test_nonempty_iota() {
// Default ctr
{
std::ranges::iota_view<Int42<DefaultTo42>> iv;
assert(!iv.empty());
}
// Value pass
{
std::ranges::iota_view<SomeInt> iv(SomeInt(94));
assert(!iv.empty());
}
{
std::vector<char> v;
auto it = std::back_inserter(v);
auto iv = std::views::iota(it);
assert(!iv.empty());
}
{
std::vector<char> v{'b', 'a', 'b', 'a', 'z', 'm', 't'};
auto it = std::back_inserter(v);
auto iv = std::views::iota(it);
assert(!iv.empty());
}
}
constexpr bool test() {
test_empty_iota();
test_nonempty_iota();
return true;
}
int main(int, char**) {
test();
static_assert(test());
return 0;
}
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