xref: /llvm-project/libcxx/test/std/ranges/range.adaptors/range.join/ctad.verify.cpp (revision 9c4a716c1292096fcbdf415b63b7b0122b03310f)
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 
11 // template<class R>
12 //   explicit join_view(R&&) -> join_view<views::all_t<R>>;
13 
14 // Tests that the deduction guide is explicit.
15 
16 #include <ranges>
17 
18 #include "test_iterators.h"
19 
20 template<class T>
21 struct Range {
begin(Range &)22   friend T* begin(Range&) { return nullptr; }
begin(Range const &)23   friend T* begin(Range const&) { return nullptr; }
end(Range &)24   friend sentinel_wrapper<T*> end(Range&) { return sentinel_wrapper<T*>(nullptr); }
end(Range const &)25   friend sentinel_wrapper<T*> end(Range const&) { return sentinel_wrapper<T*>(nullptr); }
26 };
27 
testExplicitCTAD()28 void testExplicitCTAD() {
29   Range<Range<int>> r;
30   std::ranges::join_view v = r; // expected-error-re {{no viable constructor or deduction guide for deduction of template arguments of '{{(std::ranges::)?}}join_view'}}
31 }
32