| //===----------------------------------------------------------------------===// |
| // |
| // 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 iterator& operator+=(difference_type n) |
| // requires random_access_range<Base>; |
| // |
| // constexpr iterator& operator-=(difference_type n) |
| // requires random_access_range<Base>; |
| // |
| // friend constexpr iterator operator+(const iterator& x, difference_type y) |
| // requires random_access_range<Base>; |
| // |
| // friend constexpr iterator operator+(difference_type x, const iterator& y) |
| // requires random_access_range<Base>; |
| // |
| // friend constexpr iterator operator-(const iterator& x, difference_type y) |
| // requires random_access_range<Base>; |
| // |
| // friend constexpr difference_type operator-(const iterator& x, const iterator& y) |
| // requires sized_sentinel_for<iterator_t<Base>, iterator_t<Base>>; |
| |
| #include <ranges> |
| |
| #include <tuple> |
| |
| #include "test_iterators.h" |
| |
| template <class T, class U> |
| concept CanPlus = requires(T t, U u) { t + u; }; |
| |
| template <class T, class U> |
| concept CanPlusEqual = requires(T t, U u) { t += u; }; |
| |
| template <class T, class U> |
| concept CanMinus = requires(T t, U u) { t - u; }; |
| |
| template <class T, class U> |
| concept CanMinusEqual = requires(T t, U u) { t -= u; }; |
| |
| template <class BaseRange> |
| using ElemIter = std::ranges::iterator_t<std::ranges::elements_view<BaseRange, 0>>; |
| |
| using RandomAccessRange = std::ranges::subrange<std::tuple<int>*>; |
| static_assert(std::ranges::random_access_range<RandomAccessRange>); |
| static_assert(std::sized_sentinel_for<std::ranges::iterator_t<RandomAccessRange>, // |
| std::ranges::iterator_t<RandomAccessRange>>); |
| |
| static_assert(CanPlus<ElemIter<RandomAccessRange>, int>); |
| static_assert(CanPlus<int, ElemIter<RandomAccessRange>>); |
| static_assert(CanPlusEqual<ElemIter<RandomAccessRange>, int>); |
| static_assert(CanMinus<ElemIter<RandomAccessRange>, int>); |
| static_assert(CanMinus<ElemIter<RandomAccessRange>, ElemIter<RandomAccessRange>>); |
| static_assert(CanMinusEqual<ElemIter<RandomAccessRange>, int>); |
| |
| using BidiRange = std::ranges::subrange<bidirectional_iterator<std::tuple<int>*>>; |
| static_assert(!std::ranges::random_access_range<BidiRange>); |
| static_assert(!std::sized_sentinel_for<std::ranges::iterator_t<BidiRange>, // |
| std::ranges::iterator_t<BidiRange>>); |
| |
| static_assert(!CanPlus<ElemIter<BidiRange>, int>); |
| static_assert(!CanPlus<int, ElemIter<BidiRange>>); |
| static_assert(!CanPlusEqual<ElemIter<BidiRange>, int>); |
| static_assert(!CanMinus<ElemIter<BidiRange>, int>); |
| static_assert(!CanMinus<ElemIter<BidiRange>, ElemIter<BidiRange>>); |
| static_assert(!CanMinusEqual<ElemIter<BidiRange>, int>); |
| |
| constexpr bool test() { |
| std::tuple<int> ts[] = {{1}, {2}, {3}, {4}}; |
| |
| RandomAccessRange r{&ts[0], &ts[0] + 4}; |
| auto ev = r | std::views::elements<0>; |
| { |
| // operator+(x, n) operator+(n,x) and operator+= |
| auto it1 = ev.begin(); |
| |
| auto it2 = it1 + 3; |
| assert(it2.base() == &ts[3]); |
| |
| auto it3 = 3 + it1; |
| assert(it3.base() == &ts[3]); |
| |
| it1 += 3; |
| assert(it1 == it2); |
| assert(it1.base() == &ts[3]); |
| } |
| |
| { |
| // operator-(x, n) and operator-= |
| auto it1 = ev.end(); |
| |
| auto it2 = it1 - 3; |
| assert(it2.base() == &ts[1]); |
| |
| it1 -= 3; |
| assert(it1 == it2); |
| assert(it1.base() == &ts[1]); |
| } |
| |
| { |
| // operator-(x, y) |
| assert((ev.end() - ev.begin()) == 4); |
| |
| auto it1 = ev.begin() + 2; |
| auto it2 = ev.end() - 1; |
| assert((it1 - it2) == -1); |
| } |
| |
| return true; |
| } |
| |
| int main(int, char**) { |
| test(); |
| static_assert(test()); |
| |
| return 0; |
| } |