82 lines · cpp
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-exception6//7//===----------------------------------------------------------------------===//8 9// UNSUPPORTED: c++03, c++11, c++14, c++1710 11// constexpr auto size() requires sized_range<V>12// constexpr auto size() const requires sized_range<const V>13 14#include <ranges>15#include <cassert>16 17#include "test_macros.h"18#include "test_iterators.h"19#include "test_range.h"20#include "types.h"21 22template<class T>23concept SizeEnabled = requires(const std::ranges::take_view<T>& tv) {24 tv.size();25};26 27constexpr bool test() {28 int buffer[8] = {1, 2, 3, 4, 5, 6, 7, 8};29 30 {31 static_assert( SizeEnabled<SizedRandomAccessView>);32 static_assert(!SizeEnabled<CopyableView>);33 }34 35 {36 std::ranges::take_view<SizedRandomAccessView> tv(SizedRandomAccessView{buffer}, 0);37 assert(tv.size() == 0);38 }39 40 {41 const std::ranges::take_view<SizedRandomAccessView> tv(SizedRandomAccessView{buffer}, 2);42 assert(tv.size() == 2);43 }44 45 {46 std::ranges::take_view<SizedForwardView> tv(SizedForwardView{buffer}, 4);47 assert(tv.size() == 4);48 }49 50 {51 const std::ranges::take_view<SizedForwardView> tv(SizedForwardView{buffer}, 6);52 assert(tv.size() == 6);53 }54 55 {56 std::ranges::take_view<SizedForwardView> tv(SizedForwardView{buffer}, 8);57 assert(tv.size() == 8);58 }59 {60 const std::ranges::take_view<SizedForwardView> tv(SizedForwardView{buffer}, 8);61 assert(tv.size() == 8);62 }63 64 {65 std::ranges::take_view<SizedForwardView> tv(SizedForwardView{buffer}, 10);66 assert(tv.size() == 8);67 }68 {69 const std::ranges::take_view<SizedForwardView> tv(SizedForwardView{buffer}, 10);70 assert(tv.size() == 8);71 }72 73 return true;74}75 76int main(int, char**) {77 test();78 static_assert(test());79 80 return 0;81}82