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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
// UNSUPPORTED: libcpp-no-concepts
// UNSUPPORTED: gcc-10
// UNSUPPORTED: libcpp-has-no-incomplete-ranges
// constexpr auto size() requires sized_range<V>
// constexpr auto size() const requires sized_range<const V>
#include <ranges>
#include <cassert>
#include "test_iterators.h"
#include "test_range.h"
struct CopyableView : std::ranges::view_base {
int *ptr_;
constexpr CopyableView(int* ptr) : ptr_(ptr) {}
friend constexpr int* begin(CopyableView& view) { return view.ptr_; }
friend constexpr int* begin(CopyableView const& view) { return view.ptr_; }
friend constexpr sentinel_wrapper<int*> end(CopyableView& view) {
return sentinel_wrapper<int*>{view.ptr_ + 8};
}
friend constexpr sentinel_wrapper<int*> end(CopyableView const& view) {
return sentinel_wrapper<int*>{view.ptr_ + 8};
}
};
using ForwardIter = forward_iterator<int*>;
struct SizedForwardView : std::ranges::view_base {
int *ptr_;
constexpr SizedForwardView(int* ptr) : ptr_(ptr) {}
friend constexpr ForwardIter begin(SizedForwardView& view) { return ForwardIter(view.ptr_); }
friend constexpr ForwardIter begin(SizedForwardView const& view) { return ForwardIter(view.ptr_); }
friend constexpr sentinel_wrapper<ForwardIter> end(SizedForwardView& view) {
return sentinel_wrapper<ForwardIter>{ForwardIter(view.ptr_ + 8)};
}
friend constexpr sentinel_wrapper<ForwardIter> end(SizedForwardView const& view) {
return sentinel_wrapper<ForwardIter>{ForwardIter(view.ptr_ + 8)};
}
};
constexpr auto operator-(sentinel_wrapper<ForwardIter> sent, ForwardIter iter) {
return sent.base().base() - iter.base();
}
constexpr auto operator-(ForwardIter iter, sentinel_wrapper<ForwardIter> sent) {
return iter.base() - sent.base().base();
}
template<class T>
concept SizeEnabled = requires(const std::ranges::common_view<T>& comm) {
comm.size();
};
constexpr bool test() {
int buffer[8] = {1, 2, 3, 4, 5, 6, 7, 8};
{
static_assert( SizeEnabled<SizedForwardView>);
static_assert(!SizeEnabled<CopyableView>);
}
{
std::ranges::common_view<SizedForwardView> common(SizedForwardView{buffer});
assert(common.size() == 8);
}
{
const std::ranges::common_view<SizedForwardView> common(SizedForwardView{buffer});
assert(common.size() == 8);
}
return true;
}
int main(int, char**) {
test();
static_assert(test());
return 0;
}
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