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: no-localization |
10 | // UNSUPPORTED: c++03, c++11, c++14, c++17 |
11 | |
12 | // concept checking istream_view |
13 | |
14 | #include <istream> |
15 | #include <ranges> |
16 | |
17 | #include "test_macros.h" |
18 | |
19 | template <class Val, class CharT, class Traits = std::char_traits<CharT>> |
20 | concept HasIstreamView = requires { typename std::ranges::basic_istream_view<Val, CharT, Traits>; }; |
21 | |
22 | static_assert(HasIstreamView<int, char>); |
23 | |
24 | #ifndef TEST_HAS_NO_WIDE_CHARACTERS |
25 | static_assert(HasIstreamView<int, wchar_t>); |
26 | #endif |
27 | |
28 | // Unmovable Val |
29 | struct Unmovable { |
30 | Unmovable() = default; |
31 | Unmovable(Unmovable&&) = delete; |
32 | template <class CharT> |
33 | friend std::basic_istream<CharT>& operator>>(std::basic_istream<CharT>& x, const Unmovable&) { |
34 | return x; |
35 | } |
36 | }; |
37 | static_assert(!HasIstreamView<Unmovable, char>); |
38 | |
39 | #ifndef TEST_HAS_NO_WIDE_CHARACTERS |
40 | static_assert(!HasIstreamView<Unmovable, wchar_t>); |
41 | #endif |
42 | |
43 | // !default_initializable<Val> |
44 | struct NoDefaultCtor { |
45 | NoDefaultCtor(int) {} |
46 | friend std::istream& operator>>(std::istream& x, const NoDefaultCtor&) { return x; } |
47 | }; |
48 | static_assert(!HasIstreamView<NoDefaultCtor, char>); |
49 | #ifndef TEST_HAS_NO_WIDE_CHARACTERS |
50 | static_assert(!HasIstreamView<NoDefaultCtor, wchar_t>); |
51 | #endif |
52 | |
53 | // !stream-extractable<Val, CharT, Traits> |
54 | struct Foo {}; |
55 | static_assert(!HasIstreamView<Foo, char>); |
56 | #ifndef TEST_HAS_NO_WIDE_CHARACTERS |
57 | static_assert(!HasIstreamView<Foo, wchar_t>); |
58 | #endif |
59 | |
60 | template <class T> |
61 | concept OnlyInputRange = std::ranges::input_range<T> && !std::ranges::forward_range<T>; |
62 | |
63 | static_assert(OnlyInputRange<std::ranges::istream_view<int>>); |
64 | static_assert(OnlyInputRange<std::ranges::istream_view<long>>); |
65 | static_assert(OnlyInputRange<std::ranges::istream_view<double>>); |
66 | static_assert(OnlyInputRange<std::ranges::istream_view<char>>); |
67 | |
68 | #ifndef TEST_HAS_NO_WIDE_CHARACTERS |
69 | static_assert(OnlyInputRange<std::ranges::wistream_view<int>>); |
70 | static_assert(OnlyInputRange<std::ranges::wistream_view<long>>); |
71 | static_assert(OnlyInputRange<std::ranges::wistream_view<double>>); |
72 | static_assert(OnlyInputRange<std::ranges::wistream_view<wchar_t>>); |
73 | #endif |
74 | |