1 //===----------------------------------------------------------------------===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 9 // UNSUPPORTED: c++03, c++11, c++14, c++17 10 // UNSUPPORTED: libcpp-has-no-incomplete-ranges 11 12 // reverse_view() requires default_initializable<V> = default; 13 14 #include <ranges> 15 #include <cassert> 16 17 #include "types.h" 18 19 enum CtorKind { DefaultCtor, PtrCtor }; 20 template<CtorKind CK> 21 struct BidirRangeWith : std::ranges::view_base { 22 int *ptr_ = nullptr; 23 24 constexpr BidirRangeWith() requires (CK == DefaultCtor) = default; 25 constexpr BidirRangeWith(int *ptr); 26 beginBidirRangeWith27 constexpr bidirectional_iterator<int*> begin() { return bidirectional_iterator<int*>{ptr_}; } beginBidirRangeWith28 constexpr bidirectional_iterator<const int*> begin() const { return bidirectional_iterator<const int*>{ptr_}; } endBidirRangeWith29 constexpr bidirectional_iterator<int*> end() { return bidirectional_iterator<int*>{ptr_ + 8}; } endBidirRangeWith30 constexpr bidirectional_iterator<const int*> end() const { return bidirectional_iterator<const int*>{ptr_ + 8}; } 31 }; 32 test()33constexpr bool test() { 34 { 35 static_assert( std::default_initializable<std::ranges::reverse_view<BidirRangeWith<DefaultCtor>>>); 36 static_assert(!std::default_initializable<std::ranges::reverse_view<BidirRangeWith<PtrCtor>>>); 37 } 38 39 { 40 std::ranges::reverse_view<BidirRangeWith<DefaultCtor>> rev; 41 assert(rev.base().ptr_ == nullptr); 42 } 43 { 44 const std::ranges::reverse_view<BidirRangeWith<DefaultCtor>> rev; 45 assert(rev.base().ptr_ == nullptr); 46 } 47 48 return true; 49 } 50 main(int,char **)51int main(int, char**) { 52 test(); 53 static_assert(test()); 54 55 return 0; 56 } 57 58