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-no-concepts 11 // UNSUPPORTED: libcpp-has-no-incomplete-ranges 12 13 // constexpr auto begin() requires (!simple-view<V>); 14 // constexpr auto begin() const requires range<const V>; 15 16 #include <ranges> 17 #include <cassert> 18 19 #include "test_macros.h" 20 #include "test_iterators.h" 21 #include "test_range.h" 22 #include "types.h" 23 24 constexpr bool test() { 25 int buffer[8] = {1, 2, 3, 4, 5, 6, 7, 8}; 26 27 // sized_range && random_access_iterator 28 { 29 std::ranges::take_view<SizedRandomAccessView> tv(SizedRandomAccessView(buffer), 4); 30 assert(tv.begin() == SizedRandomAccessView(buffer).begin()); 31 ASSERT_SAME_TYPE(decltype(tv.begin()), RandomAccessIter); 32 } 33 34 { 35 const std::ranges::take_view<SizedRandomAccessView> tv(SizedRandomAccessView(buffer), 4); 36 assert(tv.begin() == SizedRandomAccessView(buffer).begin()); 37 ASSERT_SAME_TYPE(decltype(tv.begin()), RandomAccessIter); 38 } 39 40 // sized_range && !random_access_iterator 41 { 42 std::ranges::take_view<SizedForwardView> tv(SizedForwardView{buffer}, 4); 43 assert(tv.begin() == std::counted_iterator<ForwardIter>(ForwardIter(buffer), 4)); 44 ASSERT_SAME_TYPE(decltype(tv.begin()), std::counted_iterator<ForwardIter>); 45 } 46 47 { 48 const std::ranges::take_view<SizedForwardView> tv(SizedForwardView{buffer}, 4); 49 assert(tv.begin() == std::counted_iterator<ForwardIter>(ForwardIter(buffer), 4)); 50 ASSERT_SAME_TYPE(decltype(tv.begin()), std::counted_iterator<ForwardIter>); 51 } 52 53 // !sized_range 54 { 55 std::ranges::take_view<MoveOnlyView> tv(MoveOnlyView{buffer}, 4); 56 assert(tv.begin() == std::counted_iterator<int*>(buffer, 4)); 57 ASSERT_SAME_TYPE(decltype(tv.begin()), std::counted_iterator<int*>); 58 } 59 60 { 61 const std::ranges::take_view<MoveOnlyView> tv(MoveOnlyView{buffer}, 4); 62 assert(tv.begin() == std::counted_iterator<int*>(buffer, 4)); 63 ASSERT_SAME_TYPE(decltype(tv.begin()), std::counted_iterator<int*>); 64 } 65 66 return true; 67 } 68 69 int main(int, char**) { 70 test(); 71 static_assert(test()); 72 73 return 0; 74 } 75