27 template <class In, class Out = In, class Count = size_t>
28 concept HasCopyNIt = requires(In in, Count count, Out out) { std::ranges::copy_n(in, count, out); };
42 template <class In, class Out, class Sent = In>
47     std::same_as<std::ranges::in_out_result<In, Out>> auto ret =  in test_iterators()
48       std::ranges::copy_n(In(in.data()), in.size(), Out(out.data()));  in test_iterators()
57     auto ret = std::ranges::copy_n(In(in.data()), in.size(), Out(out.begin()));  in test_iterators()
63 template <class Out>
65   test_iterators<cpp20_input_iterator<int*>, Out, sentinel_wrapper<cpp20_input_iterator<int*>>>();  in test_in_iterators()
66   test_iterators<forward_iterator<int*>, Out>();  in test_in_iterators()
67   test_iterators<bidirectional_iterator<int*>, Out>();  in test_in_iterators()
68   test_iterators<random_access_iterator<int*>, Out>();  in test_in_iterators()
69   test_iterators<contiguous_iterator<int*>, Out>();  in test_in_iterators()
72 template <class Out>
74 …test_iterators<ProxyIterator<cpp20_input_iterator<int*>>, Out, sentinel_wrapper<ProxyIterator<cpp2…  in test_proxy_in_iterators()
75   test_iterators<ProxyIterator<forward_iterator<int*>>, Out>();  in test_proxy_in_iterators()
76   test_iterators<ProxyIterator<bidirectional_iterator<int*>>, Out>();  in test_proxy_in_iterators()
77   test_iterators<ProxyIterator<random_access_iterator<int*>>, Out>();  in test_proxy_in_iterators()
78   test_iterators<ProxyIterator<contiguous_iterator<int*>>, Out>();  in test_proxy_in_iterators()