xref: /llvm-project/libcxx/test/std/ranges/range.adaptors/range.join/lwg3698.pass.cpp (revision 6a664674990094c1b5d2e717256f08cb04485899)
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: c++03, c++11, c++14, c++17
10 // UNSUPPORTED: no-localization
11 
12 // Check LWG-3698: `regex_iterator` and `join_view` don't work together very well
13 
14 #include <algorithm>
15 #include <array>
16 #include <cassert>
17 #include <ranges>
18 #include <regex>
19 #include <string_view>
20 
main(int,char **)21 int main(int, char**) {
22   char const text[] = "Hello";
23   std::regex regex{"[a-z]"};
24 
25   auto lower =
26       std::ranges::subrange(
27           std::cregex_iterator(std::ranges::begin(text), std::ranges::end(text), regex), std::cregex_iterator{}) |
28       std::views::join | std::views::transform([](auto const& sm) { return std::string_view(sm.first, sm.second); });
29 
30   assert(std::ranges::equal(lower, std::to_array<std::string_view>({"e", "l", "l", "o"})));
31 
32   return 0;
33 }
34