//===----------------------------------------------------------------------===// // // 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: libcpp-has-no-incomplete-ranges // constexpr auto begin(); // constexpr auto begin() const requires range; #include #include #include "test_macros.h" #include "test_iterators.h" #include "test_range.h" struct ContiguousView : std::ranges::view_base { int *ptr_; constexpr ContiguousView(int* ptr) : ptr_(ptr) {} constexpr ContiguousView(ContiguousView&&) = default; constexpr ContiguousView& operator=(ContiguousView&&) = default; friend constexpr int* begin(ContiguousView& view) { return view.ptr_; } friend constexpr int* begin(ContiguousView const& view) { return view.ptr_; } friend constexpr sentinel_wrapper end(ContiguousView& view) { return sentinel_wrapper{view.ptr_ + 8}; } friend constexpr sentinel_wrapper end(ContiguousView const& view) { return sentinel_wrapper{view.ptr_ + 8}; } }; 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 end(CopyableView& view) { return sentinel_wrapper{view.ptr_ + 8}; } friend constexpr sentinel_wrapper end(CopyableView const& view) { return sentinel_wrapper{view.ptr_ + 8}; } }; struct MutableView : std::ranges::view_base { int *ptr_; constexpr MutableView(int* ptr) : ptr_(ptr) {} constexpr int* begin() { return ptr_; } constexpr sentinel_wrapper end() { return sentinel_wrapper{ptr_ + 8}; } }; using ForwardIter = forward_iterator; 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 end(SizedForwardView& view) { return sentinel_wrapper{ForwardIter(view.ptr_ + 8)}; } friend constexpr sentinel_wrapper end(SizedForwardView const& view) { return sentinel_wrapper{ForwardIter(view.ptr_ + 8)}; } }; // Required to make SizedForwardView a sized view. constexpr auto operator-(sentinel_wrapper sent, ForwardIter iter) { return sent.base().base() - iter.base(); } constexpr auto operator-(ForwardIter iter, sentinel_wrapper sent) { return iter.base() - sent.base().base(); } using RandomAccessIter = random_access_iterator; struct SizedRandomAccessView : std::ranges::view_base { int *ptr_; constexpr SizedRandomAccessView(int* ptr) : ptr_(ptr) {} friend constexpr RandomAccessIter begin(SizedRandomAccessView& view) { return RandomAccessIter(view.ptr_); } friend constexpr RandomAccessIter begin(SizedRandomAccessView const& view) { return RandomAccessIter(view.ptr_); } friend constexpr sentinel_wrapper end(SizedRandomAccessView& view) { return sentinel_wrapper{RandomAccessIter(view.ptr_ + 8)}; } friend constexpr sentinel_wrapper end(SizedRandomAccessView const& view) { return sentinel_wrapper{RandomAccessIter(view.ptr_ + 8)}; } }; // Required to make SizedRandomAccessView a sized view. constexpr auto operator-(sentinel_wrapper sent, RandomAccessIter iter) { return sent.base().base() - iter.base(); } constexpr auto operator-(RandomAccessIter iter, sentinel_wrapper sent) { return iter.base() - sent.base().base(); } template concept BeginEnabled = requires(const std::ranges::common_view& comm) { comm.begin(); }; constexpr bool test() { int buffer[8] = {1, 2, 3, 4, 5, 6, 7, 8}; { static_assert( BeginEnabled); static_assert(!BeginEnabled); } { std::ranges::common_view comm(SizedRandomAccessView{buffer}); assert(comm.begin() == begin(SizedRandomAccessView(buffer))); ASSERT_SAME_TYPE(decltype(comm.begin()), RandomAccessIter); } { const std::ranges::common_view comm(SizedRandomAccessView{buffer}); assert(comm.begin() == begin(SizedRandomAccessView(buffer))); ASSERT_SAME_TYPE(decltype(comm.begin()), RandomAccessIter); } return true; } int main(int, char**) { test(); static_assert(test()); // The non-constexpr tests: int buffer[8] = {1, 2, 3, 4, 5, 6, 7, 8}; { std::ranges::common_view comm(SizedForwardView{buffer}); assert(comm.begin() == begin(SizedForwardView(buffer))); ASSERT_SAME_TYPE(decltype(comm.begin()), std::common_iterator>); } { std::ranges::common_view comm(ContiguousView{buffer}); assert(comm.begin() == begin(ContiguousView(buffer))); ASSERT_SAME_TYPE(decltype(comm.begin()), std::common_iterator>); } { const std::ranges::common_view comm(SizedForwardView{buffer}); assert(comm.begin() == begin(SizedForwardView(buffer))); ASSERT_SAME_TYPE(decltype(comm.begin()), std::common_iterator>); } { const std::ranges::common_view comm(CopyableView{buffer}); assert(comm.begin() == begin(CopyableView(buffer))); ASSERT_SAME_TYPE(decltype(comm.begin()), std::common_iterator>); } return 0; }