libcxx/test/support/indirectly_readable.h

   1 // -*- C++ -*-
   2 //===----------------------------------------------------------------------===//
   3 //
   4 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   5 // See https://llvm.org/LICENSE.txt for license information.
   6 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   7 //
   8 //===----------------------------------------------------------------------===//
   9 #ifndef LIBCXX_TEST_SUPPORT_INDIRECTLY_READABLE_H
  10 #define LIBCXX_TEST_SUPPORT_INDIRECTLY_READABLE_H
  11
  12 #include <type_traits>
  13
  14 template <class Token>
  15 struct Common { };
  16
  17 template <class Token>
  18 struct T1 : Common<Token> { };
  19
  20 template <class Token>
  21 struct T2 : Common<Token> { };
  22
  23 template <template <class> class T1Qual, template <class> class T2Qual, class Token>
  24 struct std::basic_common_reference<T1<Token>, T2<Token>, T1Qual, T2Qual> {
  25   using type = Common<Token>;
  26 };
  27 template <template <class> class T2Qual, template <class> class T1Qual, class Token>
  28 struct std::basic_common_reference<T2<Token>, T1<Token>, T2Qual, T1Qual>
  29   : std::basic_common_reference<T1<Token>, T2<Token>, T1Qual, T2Qual>
  30 { };
  31
  32 template <class Token>
  33 struct IndirectlyReadable {
  34   using value_type = T1<Token>;
  35   T2<Token>& operator*() const;
  36 };
  37
  38 #endif // LIBCXX_TEST_SUPPORT_INDIRECTLY_READABLE_H