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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 sentinel(sentinel<!Const> s)
// requires Const && convertible_to<sentinel_t<V>, sentinel_t<Base>>;
#include <cassert>
#include <ranges>
#include "../types.h"
struct Sent {
int i;
constexpr Sent() = default;
constexpr Sent(int ii) : i(ii) {}
friend constexpr bool operator==(int* iter, const Sent& s) { return s.i > *iter; }
};
struct ConstSent {
int i;
constexpr ConstSent() = default;
constexpr ConstSent(int ii) : i(ii) {}
constexpr ConstSent(const Sent& s) : i(s.i) {}
friend constexpr bool operator==(int* iter, const ConstSent& s) { return s.i > *iter; }
};
struct Range : std::ranges::view_base {
int* begin() const;
Sent end();
ConstSent end() const;
};
struct Pred {
bool operator()(int i) const;
};
struct NonConvertConstSent {
int i;
constexpr NonConvertConstSent() = default;
constexpr NonConvertConstSent(int ii) : i(ii) {}
friend constexpr bool operator==(int* iter, const NonConvertConstSent& s) { return s.i > *iter; }
};
struct NonConvertConstSentRange : std::ranges::view_base {
int* begin() const;
Sent end();
NonConvertConstSent end() const;
};
// Test Constraint
static_assert(std::is_constructible_v<std::ranges::sentinel_t<const std::ranges::take_while_view<Range, Pred>>,
std::ranges::sentinel_t<std::ranges::take_while_view<Range, Pred>>>);
// !Const
static_assert(!std::is_constructible_v<std::ranges::sentinel_t<std::ranges::take_while_view<Range, Pred>>,
std::ranges::sentinel_t<const std::ranges::take_while_view<Range, Pred>>>);
// !convertible_to<sentinel_t<V>, sentinel_t<Base>>
static_assert(!std::is_constructible_v<
std::ranges::sentinel_t<const std::ranges::take_while_view<NonConvertConstSentRange, Pred>>,
std::ranges::sentinel_t<std::ranges::take_while_view<NonConvertConstSentRange, Pred>>>);
constexpr bool test() {
// base is init correctly
{
using R = std::ranges::take_while_view<Range, bool (*)(int)>;
using Sentinel = std::ranges::sentinel_t<R>;
using ConstSentinel = std::ranges::sentinel_t<const R>;
static_assert(!std::same_as<Sentinel, ConstSentinel>);
Sentinel s1(Sent{5}, nullptr);
ConstSentinel s2 = s1;
assert(s2.base().i == 5);
}
// pred is init correctly
{
bool called = false;
auto pred = [&](int) {
called = true;
return false;
};
using R = std::ranges::take_while_view<Range, decltype(pred)>;
using Sentinel = std::ranges::sentinel_t<R>;
using ConstSentinel = std::ranges::sentinel_t<const R>;
static_assert(!std::same_as<Sentinel, ConstSentinel>);
int i = 10;
int* iter = &i;
Sentinel s1(Sent{0}, &pred);
ConstSentinel s2 = s1;
[[maybe_unused]] bool b = iter == s2;
assert(called);
}
// LWG 3708 `take_while_view::sentinel`'s conversion constructor should move
{
struct MoveOnlyConvert {
int i;
constexpr MoveOnlyConvert() = default;
constexpr MoveOnlyConvert(Sent&& s) : i(s.i) { s.i = 0; }
constexpr bool operator==(int* iter) const { return i > *iter; }
};
struct Rng : std::ranges::view_base {
int* begin() const;
Sent end();
MoveOnlyConvert end() const;
};
using R = std::ranges::take_while_view<Rng, Pred>;
using Sentinel = std::ranges::sentinel_t<R>;
using ConstSentinel = std::ranges::sentinel_t<const R>;
static_assert(!std::same_as<Sentinel, ConstSentinel>);
Sentinel s1(Sent{5}, nullptr);
ConstSentinel s2 = s1;
assert(s2.base().i == 5);
}
return true;
}
int main(int, char**) {
test();
static_assert(test());
return 0;
}
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