xref: /llvm-project/libcxx/test/std/ranges/range.factories/range.istream.view/cpo.pass.cpp (revision 60a6a0d17ad5afcac5c71dcf9a05f8c814951804)
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 // std::views::istream<T>
13 
14 #include <cassert>
15 #include <ranges>
16 #include <sstream>
17 #include <type_traits>
18 
19 #include "test_macros.h"
20 #include "utils.h"
21 
22 static_assert(!std::is_invocable_v<decltype((std::views::istream<int>))>);
23 static_assert(std::is_invocable_v<decltype((std::views::istream<int>)), std::istream&>);
24 static_assert(!std::is_invocable_v<decltype((std::views::istream<int>)), const std::istream&>);
25 static_assert(!std::is_invocable_v<decltype((std::views::istream<int>)), int>);
26 
27 #ifndef TEST_HAS_NO_WIDE_CHARACTERS
28 static_assert(std::is_invocable_v<decltype((std::views::istream<int>)), std::wistream&>);
29 static_assert(!std::is_invocable_v<decltype((std::views::istream<int>)), const std::wistream&>);
30 #endif
31 
32 template <class CharT>
test()33 void test() {
34   auto iss = make_string_stream<CharT>("12   3");
35   auto isv = std::views::istream<int>(iss);
36   auto it  = isv.begin();
37   assert(*it == 12);
38 }
39 
main(int,char **)40 int main(int, char**) {
41   test<char>();
42 #ifndef TEST_HAS_NO_WIDE_CHARACTERS
43   test<wchar_t>();
44 #endif
45 
46   return 0;
47 }
48