//===----------------------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//

// UNSUPPORTED: c++03, c++11, c++14, c++17

// template<class T, class U>
// concept equality_comparable_with = // see below

#include <concepts>

#include <array>
#include <cstddef>
#include <deque>
#include <forward_list>
#include <list>
#include <map>
#include <optional>
#include <vector>

#include "test_macros.h"

#ifndef TEST_HAS_NO_THREADS
#  include <mutex>
#endif

#include "compare_types.h"

template <class T, class U>
constexpr bool check_equality_comparable_with() {
  constexpr bool result = std::equality_comparable_with<T, U>;
  static_assert(std::equality_comparable_with<U, T> == result);
  static_assert(std::equality_comparable_with<T, U const> == result);
  static_assert(std::equality_comparable_with<T const, U const> == result);
  static_assert(std::equality_comparable_with<T, U const&> == result);
  static_assert(std::equality_comparable_with<T const, U const&> == result);
  static_assert(std::equality_comparable_with<T&, U const> == result);
  static_assert(std::equality_comparable_with<T const&, U const> == result);
  static_assert(std::equality_comparable_with<T&, U const&> == result);
  static_assert(std::equality_comparable_with<T const&, U const&> == result);
  static_assert(std::equality_comparable_with<T, U const&&> == result);
  static_assert(std::equality_comparable_with<T const, U const&&> == result);
  static_assert(std::equality_comparable_with<T&, U const&&> == result);
  static_assert(std::equality_comparable_with<T const&, U const&&> == result);
  static_assert(std::equality_comparable_with<T&&, U const> == result);
  static_assert(std::equality_comparable_with<T const&&, U const> == result);
  static_assert(std::equality_comparable_with<T&&, U const&> == result);
  static_assert(std::equality_comparable_with<T const&&, U const&> == result);
  static_assert(std::equality_comparable_with<T&&, U const&&> == result);
  static_assert(std::equality_comparable_with<T const&&, U const&&> == result);
  return result;
}

namespace fundamentals {
static_assert(check_equality_comparable_with<int, int>());
static_assert(check_equality_comparable_with<int, bool>());
static_assert(check_equality_comparable_with<int, char>());
static_assert(check_equality_comparable_with<int, wchar_t>());
static_assert(check_equality_comparable_with<int, double>());
static_assert(!check_equality_comparable_with<int, int*>());
static_assert(!check_equality_comparable_with<int, int[5]>());
static_assert(!check_equality_comparable_with<int, int (*)()>());
static_assert(!check_equality_comparable_with<int, int (&)()>());

struct S {};
static_assert(!check_equality_comparable_with<int, int S::*>());
static_assert(!check_equality_comparable_with<int, int (S::*)()>());
static_assert(!check_equality_comparable_with<int, int (S::*)() noexcept>());
static_assert(!check_equality_comparable_with<int, int (S::*)() const>());
static_assert(
    !check_equality_comparable_with<int, int (S::*)() const noexcept>());
static_assert(!check_equality_comparable_with<int, int (S::*)() volatile>());
static_assert(
    !check_equality_comparable_with<int, int (S::*)() volatile noexcept>());
static_assert(
    !check_equality_comparable_with<int, int (S::*)() const volatile>());
static_assert(!check_equality_comparable_with<
              int, int (S::*)() const volatile noexcept>());
static_assert(!check_equality_comparable_with<int, int (S::*)() &>());
static_assert(!check_equality_comparable_with<int, int (S::*)() & noexcept>());
static_assert(!check_equality_comparable_with<int, int (S::*)() const&>());
static_assert(
    !check_equality_comparable_with<int, int (S::*)() const & noexcept>());
static_assert(!check_equality_comparable_with<int, int (S::*)() volatile&>());
static_assert(
    !check_equality_comparable_with<int, int (S::*)() volatile & noexcept>());
static_assert(
    !check_equality_comparable_with<int, int (S::*)() const volatile&>());
static_assert(!check_equality_comparable_with<int, int (S::*)() const volatile &
                                                       noexcept>());
static_assert(!check_equality_comparable_with<int, int (S::*)() &&>());
static_assert(!check_equality_comparable_with < int,
              int (S::*)() && noexcept > ());
static_assert(!check_equality_comparable_with<int, int (S::*)() const&&>());
static_assert(!check_equality_comparable_with < int,
              int (S::*)() const&& noexcept > ());
static_assert(!check_equality_comparable_with<int, int (S::*)() volatile&&>());
static_assert(!check_equality_comparable_with < int,
              int (S::*)() volatile&& noexcept > ());
static_assert(
    !check_equality_comparable_with<int, int (S::*)() const volatile&&>());
static_assert(!check_equality_comparable_with < int,
              int (S::*)() const volatile&& noexcept > ());

static_assert(check_equality_comparable_with<int*, int*>());
static_assert(check_equality_comparable_with<int*, int[5]>());
static_assert(!check_equality_comparable_with<int*, int (*)()>());
static_assert(!check_equality_comparable_with<int*, int (&)()>());
static_assert(!check_equality_comparable_with<int*, int (S::*)()>());
static_assert(!check_equality_comparable_with<int*, int (S::*)() noexcept>());
static_assert(!check_equality_comparable_with<int*, int (S::*)() const>());
static_assert(
    !check_equality_comparable_with<int*, int (S::*)() const noexcept>());
static_assert(!check_equality_comparable_with<int*, int (S::*)() volatile>());
static_assert(
    !check_equality_comparable_with<int*, int (S::*)() volatile noexcept>());
static_assert(
    !check_equality_comparable_with<int*, int (S::*)() const volatile>());
static_assert(!check_equality_comparable_with<
              int*, int (S::*)() const volatile noexcept>());
static_assert(!check_equality_comparable_with<int*, int (S::*)() &>());
static_assert(!check_equality_comparable_with<int*, int (S::*)() & noexcept>());
static_assert(!check_equality_comparable_with<int*, int (S::*)() const&>());
static_assert(
    !check_equality_comparable_with<int*, int (S::*)() const & noexcept>());
static_assert(!check_equality_comparable_with<int*, int (S::*)() volatile&>());
static_assert(
    !check_equality_comparable_with<int*, int (S::*)() volatile & noexcept>());
static_assert(
    !check_equality_comparable_with<int*, int (S::*)() const volatile&>());
static_assert(!check_equality_comparable_with<
              int*, int (S::*)() const volatile & noexcept>());
static_assert(!check_equality_comparable_with<int*, int (S::*)() &&>());
static_assert(!check_equality_comparable_with < int*,
              int (S::*)() && noexcept > ());
static_assert(!check_equality_comparable_with<int*, int (S::*)() const&&>());
static_assert(!check_equality_comparable_with < int*,
              int (S::*)() const&& noexcept > ());
static_assert(!check_equality_comparable_with<int*, int (S::*)() volatile&&>());
static_assert(!check_equality_comparable_with < int*,
              int (S::*)() volatile&& noexcept > ());
static_assert(
    !check_equality_comparable_with<int*, int (S::*)() const volatile&&>());
static_assert(!check_equality_comparable_with < int*,
              int (S::*)() const volatile&& noexcept > ());

static_assert(check_equality_comparable_with<int[5], int[5]>());
static_assert(!check_equality_comparable_with<int[5], int (*)()>());
static_assert(!check_equality_comparable_with<int[5], int (&)()>());
static_assert(!check_equality_comparable_with<int[5], int (S::*)()>());
static_assert(!check_equality_comparable_with<int[5], int (S::*)() noexcept>());
static_assert(!check_equality_comparable_with<int[5], int (S::*)() const>());
static_assert(
    !check_equality_comparable_with<int[5], int (S::*)() const noexcept>());
static_assert(!check_equality_comparable_with<int[5], int (S::*)() volatile>());
static_assert(
    !check_equality_comparable_with<int[5], int (S::*)() volatile noexcept>());
static_assert(
    !check_equality_comparable_with<int[5], int (S::*)() const volatile>());
static_assert(!check_equality_comparable_with<
              int[5], int (S::*)() const volatile noexcept>());
static_assert(!check_equality_comparable_with<int[5], int (S::*)() &>());
static_assert(
    !check_equality_comparable_with<int[5], int (S::*)() & noexcept>());
static_assert(!check_equality_comparable_with<int[5], int (S::*)() const&>());
static_assert(
    !check_equality_comparable_with<int[5], int (S::*)() const & noexcept>());
static_assert(
    !check_equality_comparable_with<int[5], int (S::*)() volatile&>());
static_assert(!check_equality_comparable_with<int[5], int (S::*)() volatile &
                                                          noexcept>());
static_assert(
    !check_equality_comparable_with<int[5], int (S::*)() const volatile&>());
static_assert(!check_equality_comparable_with<
              int[5], int (S::*)() const volatile & noexcept>());
static_assert(!check_equality_comparable_with<int[5], int (S::*)() &&>());
static_assert(!check_equality_comparable_with < int[5],
              int (S::*)() && noexcept > ());
static_assert(!check_equality_comparable_with<int[5], int (S::*)() const&&>());
static_assert(!check_equality_comparable_with < int[5],
              int (S::*)() const&& noexcept > ());
static_assert(
    !check_equality_comparable_with<int[5], int (S::*)() volatile&&>());
static_assert(!check_equality_comparable_with < int[5],
              int (S::*)() volatile&& noexcept > ());
static_assert(
    !check_equality_comparable_with<int[5], int (S::*)() const volatile&&>());
static_assert(!check_equality_comparable_with < int[5],
              int (S::*)() const volatile&& noexcept > ());

static_assert(check_equality_comparable_with<int (*)(), int (*)()>());
static_assert(check_equality_comparable_with<int (*)(), int (&)()>());
static_assert(!check_equality_comparable_with<int (*)(), int (S::*)()>());
static_assert(
    !check_equality_comparable_with<int (*)(), int (S::*)() noexcept>());
static_assert(!check_equality_comparable_with<int (*)(), int (S::*)() const>());
static_assert(
    !check_equality_comparable_with<int (*)(), int (S::*)() const noexcept>());
static_assert(
    !check_equality_comparable_with<int (*)(), int (S::*)() volatile>());
static_assert(!check_equality_comparable_with<
              int (*)(), int (S::*)() volatile noexcept>());
static_assert(
    !check_equality_comparable_with<int (*)(), int (S::*)() const volatile>());
static_assert(!check_equality_comparable_with<
              int (*)(), int (S::*)() const volatile noexcept>());
static_assert(!check_equality_comparable_with<int (*)(), int (S::*)() &>());
static_assert(
    !check_equality_comparable_with<int (*)(), int (S::*)() & noexcept>());
static_assert(
    !check_equality_comparable_with<int (*)(), int (S::*)() const&>());
static_assert(!check_equality_comparable_with<int (*)(),
                                              int (S::*)() const & noexcept>());
static_assert(
    !check_equality_comparable_with<int (*)(), int (S::*)() volatile&>());
static_assert(!check_equality_comparable_with<int (*)(), int (S::*)() volatile &
                                                             noexcept>());
static_assert(
    !check_equality_comparable_with<int (*)(), int (S::*)() const volatile&>());
static_assert(!check_equality_comparable_with<
              int (*)(), int (S::*)() const volatile & noexcept>());
static_assert(!check_equality_comparable_with<int (*)(), int (S::*)() &&>());
static_assert(!check_equality_comparable_with < int (*)(),
              int (S::*)() && noexcept > ());
static_assert(
    !check_equality_comparable_with<int (*)(), int (S::*)() const&&>());
static_assert(!check_equality_comparable_with < int (*)(),
              int (S::*)() const&& noexcept > ());
static_assert(
    !check_equality_comparable_with<int (*)(), int (S::*)() volatile&&>());
static_assert(!check_equality_comparable_with < int (*)(),
              int (S::*)() volatile&& noexcept > ());
static_assert(!check_equality_comparable_with<int (*)(),
                                              int (S::*)() const volatile&&>());
static_assert(!check_equality_comparable_with < int (*)(),
              int (S::*)() const volatile&& noexcept > ());

static_assert(check_equality_comparable_with<int (&)(), int (&)()>());
static_assert(!check_equality_comparable_with<int (&)(), int (S::*)()>());
static_assert(
    !check_equality_comparable_with<int (&)(), int (S::*)() noexcept>());
static_assert(!check_equality_comparable_with<int (&)(), int (S::*)() const>());
static_assert(
    !check_equality_comparable_with<int (&)(), int (S::*)() const noexcept>());
static_assert(
    !check_equality_comparable_with<int (&)(), int (S::*)() volatile>());
static_assert(!check_equality_comparable_with<
              int (&)(), int (S::*)() volatile noexcept>());
static_assert(
    !check_equality_comparable_with<int (&)(), int (S::*)() const volatile>());
static_assert(!check_equality_comparable_with<
              int (&)(), int (S::*)() const volatile noexcept>());
static_assert(!check_equality_comparable_with<int (&)(), int (S::*)() &>());
static_assert(
    !check_equality_comparable_with<int (&)(), int (S::*)() & noexcept>());
static_assert(
    !check_equality_comparable_with<int (&)(), int (S::*)() const&>());
static_assert(!check_equality_comparable_with<int (&)(),
                                              int (S::*)() const & noexcept>());
static_assert(
    !check_equality_comparable_with<int (&)(), int (S::*)() volatile&>());
static_assert(!check_equality_comparable_with<int (&)(), int (S::*)() volatile &
                                                             noexcept>());
static_assert(
    !check_equality_comparable_with<int (&)(), int (S::*)() const volatile&>());
static_assert(!check_equality_comparable_with<
              int (&)(), int (S::*)() const volatile & noexcept>());
static_assert(!check_equality_comparable_with<int (&)(), int (S::*)() &&>());
static_assert(!check_equality_comparable_with < int (&)(),
              int (S::*)() && noexcept > ());
static_assert(
    !check_equality_comparable_with<int (&)(), int (S::*)() const&&>());
static_assert(!check_equality_comparable_with < int (&)(),
              int (S::*)() const&& noexcept > ());
static_assert(
    !check_equality_comparable_with<int (&)(), int (S::*)() volatile&&>());
static_assert(!check_equality_comparable_with < int (&)(),
              int (S::*)() volatile&& noexcept > ());
static_assert(!check_equality_comparable_with<int (&)(),
                                              int (S::*)() const volatile&&>());
static_assert(!check_equality_comparable_with < int (&)(),
              int (S::*)() const volatile&& noexcept > ());

static_assert(check_equality_comparable_with<int (S::*)(), int (S::*)()>());
static_assert(
    check_equality_comparable_with<int (S::*)(), int (S::*)() noexcept>());
static_assert(
    !check_equality_comparable_with<int (S::*)(), int (S::*)() const>());
static_assert(!check_equality_comparable_with<int (S::*)(),
                                              int (S::*)() const noexcept>());
static_assert(
    !check_equality_comparable_with<int (S::*)(), int (S::*)() volatile>());
static_assert(!check_equality_comparable_with<
              int (S::*)(), int (S::*)() volatile noexcept>());
static_assert(!check_equality_comparable_with<int (S::*)(),
                                              int (S::*)() const volatile>());
static_assert(!check_equality_comparable_with<
              int (S::*)(), int (S::*)() const volatile noexcept>());
static_assert(!check_equality_comparable_with<int (S::*)(), int (S::*)() &>());
static_assert(
    !check_equality_comparable_with<int (S::*)(), int (S::*)() & noexcept>());
static_assert(
    !check_equality_comparable_with<int (S::*)(), int (S::*)() const&>());
static_assert(!check_equality_comparable_with<int (S::*)(),
                                              int (S::*)() const & noexcept>());
static_assert(
    !check_equality_comparable_with<int (S::*)(), int (S::*)() volatile&>());
static_assert(!check_equality_comparable_with<
              int (S::*)(), int (S::*)() volatile & noexcept>());
static_assert(!check_equality_comparable_with<int (S::*)(),
                                              int (S::*)() const volatile&>());
static_assert(!check_equality_comparable_with<
              int (S::*)(), int (S::*)() const volatile & noexcept>());
static_assert(!check_equality_comparable_with<int (S::*)(), int (S::*)() &&>());
static_assert(!check_equality_comparable_with < int (S::*)(),
              int (S::*)() && noexcept > ());
static_assert(
    !check_equality_comparable_with<int (S::*)(), int (S::*)() const&&>());
static_assert(!check_equality_comparable_with < int (S::*)(),
              int (S::*)() const&& noexcept > ());
static_assert(
    !check_equality_comparable_with<int (S::*)(), int (S::*)() volatile&&>());
static_assert(!check_equality_comparable_with < int (S::*)(),
              int (S::*)() volatile&& noexcept > ());
static_assert(!check_equality_comparable_with<int (S::*)(),
                                              int (S::*)() const volatile&&>());
static_assert(!check_equality_comparable_with < int (S::*)(),
              int (S::*)() const volatile&& noexcept > ());

static_assert(check_equality_comparable_with<int (S::*)() noexcept,
                                             int (S::*)() noexcept>());
static_assert(!check_equality_comparable_with<int (S::*)() noexcept,
                                              int (S::*)() const>());
static_assert(!check_equality_comparable_with<int (S::*)() noexcept,
                                              int (S::*)() const noexcept>());
static_assert(!check_equality_comparable_with<int (S::*)() noexcept,
                                              int (S::*)() volatile>());
static_assert(!check_equality_comparable_with<
              int (S::*)() noexcept, int (S::*)() volatile noexcept>());
static_assert(!check_equality_comparable_with<int (S::*)() noexcept,
                                              int (S::*)() const volatile>());
static_assert(!check_equality_comparable_with<
              int (S::*)() noexcept, int (S::*)() const volatile noexcept>());
static_assert(
    !check_equality_comparable_with<int (S::*)() noexcept, int (S::*)() &>());
static_assert(!check_equality_comparable_with<int (S::*)() noexcept,
                                              int (S::*)() & noexcept>());
static_assert(!check_equality_comparable_with<int (S::*)() noexcept,
                                              int (S::*)() const&>());
static_assert(!check_equality_comparable_with<int (S::*)() noexcept,
                                              int (S::*)() const & noexcept>());
static_assert(!check_equality_comparable_with<int (S::*)() noexcept,
                                              int (S::*)() volatile&>());
static_assert(!check_equality_comparable_with<
              int (S::*)() noexcept, int (S::*)() volatile & noexcept>());
static_assert(!check_equality_comparable_with<int (S::*)() noexcept,
                                              int (S::*)() const volatile&>());
static_assert(!check_equality_comparable_with<
              int (S::*)() noexcept, int (S::*)() const volatile & noexcept>());
static_assert(
    !check_equality_comparable_with<int (S::*)() noexcept, int (S::*)() &&>());
static_assert(!check_equality_comparable_with < int (S::*)() noexcept,
              int (S::*)() && noexcept > ());
static_assert(!check_equality_comparable_with<int (S::*)() noexcept,
                                              int (S::*)() const&&>());
static_assert(!check_equality_comparable_with < int (S::*)() noexcept,
              int (S::*)() const&& noexcept > ());
static_assert(!check_equality_comparable_with<int (S::*)() noexcept,
                                              int (S::*)() volatile&&>());
static_assert(!check_equality_comparable_with < int (S::*)() noexcept,
              int (S::*)() volatile&& noexcept > ());
static_assert(!check_equality_comparable_with<int (S::*)() noexcept,
                                              int (S::*)() const volatile&&>());
static_assert(!check_equality_comparable_with < int (S::*)() noexcept,
              int (S::*)() const volatile&& noexcept > ());

static_assert(
    check_equality_comparable_with<int (S::*)() const, int (S::*)() const>());
static_assert(check_equality_comparable_with<int (S::*)() const,
                                             int (S::*)() const noexcept>());
static_assert(!check_equality_comparable_with<int (S::*)() const,
                                              int (S::*)() volatile>());
static_assert(!check_equality_comparable_with<
              int (S::*)() const, int (S::*)() volatile noexcept>());
static_assert(!check_equality_comparable_with<int (S::*)() const,
                                              int (S::*)() const volatile>());
static_assert(!check_equality_comparable_with<
              int (S::*)() const, int (S::*)() const volatile noexcept>());
static_assert(
    !check_equality_comparable_with<int (S::*)() const, int (S::*)() &>());
static_assert(!check_equality_comparable_with<int (S::*)() const,
                                              int (S::*)() & noexcept>());
static_assert(
    !check_equality_comparable_with<int (S::*)() const, int (S::*)() const&>());
static_assert(!check_equality_comparable_with<int (S::*)() const,
                                              int (S::*)() const & noexcept>());
static_assert(!check_equality_comparable_with<int (S::*)() const,
                                              int (S::*)() volatile&>());
static_assert(!check_equality_comparable_with<
              int (S::*)() const, int (S::*)() volatile & noexcept>());
static_assert(!check_equality_comparable_with<int (S::*)() const,
                                              int (S::*)() const volatile&>());
static_assert(!check_equality_comparable_with<
              int (S::*)() const, int (S::*)() const volatile & noexcept>());
static_assert(
    !check_equality_comparable_with<int (S::*)() const, int (S::*)() &&>());
static_assert(!check_equality_comparable_with < int (S::*)() const,
              int (S::*)() && noexcept > ());
static_assert(!check_equality_comparable_with<int (S::*)() const,
                                              int (S::*)() const&&>());
static_assert(!check_equality_comparable_with < int (S::*)() const,
              int (S::*)() const&& noexcept > ());
static_assert(!check_equality_comparable_with<int (S::*)() const,
                                              int (S::*)() volatile&&>());
static_assert(!check_equality_comparable_with < int (S::*)() const,
              int (S::*)() volatile&& noexcept > ());
static_assert(!check_equality_comparable_with<int (S::*)() const,
                                              int (S::*)() const volatile&&>());
static_assert(!check_equality_comparable_with < int (S::*)() const,
              int (S::*)() const volatile&& noexcept > ());

static_assert(check_equality_comparable_with<int (S::*)() const noexcept,
                                             int (S::*)() const noexcept>());
static_assert(!check_equality_comparable_with<int (S::*)() const noexcept,
                                              int (S::*)() volatile>());
static_assert(!check_equality_comparable_with<
              int (S::*)() const noexcept, int (S::*)() volatile noexcept>());
static_assert(!check_equality_comparable_with<int (S::*)() const noexcept,
                                              int (S::*)() const volatile>());
static_assert(
    !check_equality_comparable_with<int (S::*)() const noexcept,
                                    int (S::*)() const volatile noexcept>());
static_assert(!check_equality_comparable_with<int (S::*)() const noexcept,
                                              int (S::*)() &>());
static_assert(!check_equality_comparable_with<int (S::*)() const noexcept,
                                              int (S::*)() & noexcept>());
static_assert(!check_equality_comparable_with<int (S::*)() const noexcept,
                                              int (S::*)() const&>());
static_assert(!check_equality_comparable_with<int (S::*)() const noexcept,
                                              int (S::*)() const & noexcept>());
static_assert(!check_equality_comparable_with<int (S::*)() const noexcept,
                                              int (S::*)() volatile&>());
static_assert(!check_equality_comparable_with<
              int (S::*)() const noexcept, int (S::*)() volatile & noexcept>());
static_assert(!check_equality_comparable_with<int (S::*)() const noexcept,
                                              int (S::*)() const volatile&>());
static_assert(
    !check_equality_comparable_with<int (S::*)() const noexcept,
                                    int (S::*)() const volatile & noexcept>());
static_assert(!check_equality_comparable_with<int (S::*)() const noexcept,
                                              int (S::*)() &&>());
static_assert(!check_equality_comparable_with < int (S::*)() const noexcept,
              int (S::*)() && noexcept > ());
static_assert(!check_equality_comparable_with<int (S::*)() const noexcept,
                                              int (S::*)() const&&>());
static_assert(!check_equality_comparable_with < int (S::*)() const noexcept,
              int (S::*)() const&& noexcept > ());
static_assert(!check_equality_comparable_with<int (S::*)() const noexcept,
                                              int (S::*)() volatile&&>());
static_assert(!check_equality_comparable_with < int (S::*)() const noexcept,
              int (S::*)() volatile&& noexcept > ());
static_assert(!check_equality_comparable_with<int (S::*)() const noexcept,
                                              int (S::*)() const volatile&&>());
static_assert(!check_equality_comparable_with < int (S::*)() const noexcept,
              int (S::*)() const volatile&& noexcept > ());

static_assert(check_equality_comparable_with<int (S::*)() volatile,
                                             int (S::*)() volatile>());
static_assert(check_equality_comparable_with<int (S::*)() volatile,
                                             int (S::*)() volatile noexcept>());
static_assert(!check_equality_comparable_with<int (S::*)() volatile,
                                              int (S::*)() const volatile>());
static_assert(!check_equality_comparable_with<
              int (S::*)() volatile, int (S::*)() const volatile noexcept>());
static_assert(
    !check_equality_comparable_with<int (S::*)() volatile, int (S::*)() &>());
static_assert(!check_equality_comparable_with<int (S::*)() volatile,
                                              int (S::*)() & noexcept>());
static_assert(!check_equality_comparable_with<int (S::*)() volatile,
                                              int (S::*)() const&>());
static_assert(!check_equality_comparable_with<int (S::*)() volatile,
                                              int (S::*)() const & noexcept>());
static_assert(!check_equality_comparable_with<int (S::*)() volatile,
                                              int (S::*)() volatile&>());
static_assert(!check_equality_comparable_with<
              int (S::*)() volatile, int (S::*)() volatile & noexcept>());
static_assert(!check_equality_comparable_with<int (S::*)() volatile,
                                              int (S::*)() const volatile&>());
static_assert(!check_equality_comparable_with<
              int (S::*)() volatile, int (S::*)() const volatile & noexcept>());
static_assert(
    !check_equality_comparable_with<int (S::*)() volatile, int (S::*)() &&>());
static_assert(!check_equality_comparable_with < int (S::*)() volatile,
              int (S::*)() && noexcept > ());
static_assert(!check_equality_comparable_with<int (S::*)() volatile,
                                              int (S::*)() const&&>());
static_assert(!check_equality_comparable_with < int (S::*)() volatile,
              int (S::*)() const&& noexcept > ());
static_assert(!check_equality_comparable_with<int (S::*)() volatile,
                                              int (S::*)() volatile&&>());
static_assert(!check_equality_comparable_with < int (S::*)() volatile,
              int (S::*)() volatile&& noexcept > ());
static_assert(!check_equality_comparable_with<int (S::*)() volatile,
                                              int (S::*)() const volatile&&>());
static_assert(!check_equality_comparable_with < int (S::*)() volatile,
              int (S::*)() const volatile&& noexcept > ());

static_assert(check_equality_comparable_with<int (S::*)() volatile noexcept,
                                             int (S::*)() volatile noexcept>());
static_assert(!check_equality_comparable_with<int (S::*)() volatile noexcept,
                                              int (S::*)() const volatile>());
static_assert(
    !check_equality_comparable_with<int (S::*)() volatile noexcept,
                                    int (S::*)() const volatile noexcept>());
static_assert(!check_equality_comparable_with<int (S::*)() volatile noexcept,
                                              int (S::*)() &>());
static_assert(!check_equality_comparable_with<int (S::*)() volatile noexcept,
                                              int (S::*)() & noexcept>());
static_assert(!check_equality_comparable_with<int (S::*)() volatile noexcept,
                                              int (S::*)() const&>());
static_assert(!check_equality_comparable_with<int (S::*)() volatile noexcept,
                                              int (S::*)() const & noexcept>());
static_assert(!check_equality_comparable_with<int (S::*)() volatile noexcept,
                                              int (S::*)() volatile&>());
static_assert(
    !check_equality_comparable_with<int (S::*)() volatile noexcept,
                                    int (S::*)() volatile & noexcept>());
static_assert(!check_equality_comparable_with<int (S::*)() volatile noexcept,
                                              int (S::*)() const volatile&>());
static_assert(
    !check_equality_comparable_with<int (S::*)() volatile noexcept,
                                    int (S::*)() const volatile & noexcept>());
static_assert(!check_equality_comparable_with<int (S::*)() volatile noexcept,
                                              int (S::*)() &&>());
static_assert(!check_equality_comparable_with < int (S::*)() volatile noexcept,
              int (S::*)() && noexcept > ());
static_assert(!check_equality_comparable_with<int (S::*)() volatile noexcept,
                                              int (S::*)() const&&>());
static_assert(!check_equality_comparable_with < int (S::*)() volatile noexcept,
              int (S::*)() const&& noexcept > ());
static_assert(!check_equality_comparable_with<int (S::*)() volatile noexcept,
                                              int (S::*)() volatile&&>());
static_assert(!check_equality_comparable_with < int (S::*)() volatile noexcept,
              int (S::*)() volatile&& noexcept > ());
static_assert(!check_equality_comparable_with<int (S::*)() volatile noexcept,
                                              int (S::*)() const volatile&&>());
static_assert(!check_equality_comparable_with < int (S::*)() volatile noexcept,
              int (S::*)() const volatile&& noexcept > ());

static_assert(check_equality_comparable_with<int (S::*)() const volatile,
                                             int (S::*)() const volatile>());
static_assert(
    check_equality_comparable_with<int (S::*)() const volatile,
                                   int (S::*)() const volatile noexcept>());
static_assert(!check_equality_comparable_with<int (S::*)() const volatile,
                                              int (S::*)() &>());
static_assert(!check_equality_comparable_with<int (S::*)() const volatile,
                                              int (S::*)() & noexcept>());
static_assert(!check_equality_comparable_with<int (S::*)() const volatile,
                                              int (S::*)() const&>());
static_assert(!check_equality_comparable_with<int (S::*)() const volatile,
                                              int (S::*)() const & noexcept>());
static_assert(!check_equality_comparable_with<int (S::*)() const volatile,
                                              int (S::*)() volatile&>());
static_assert(!check_equality_comparable_with<
              int (S::*)() const volatile, int (S::*)() volatile & noexcept>());
static_assert(!check_equality_comparable_with<int (S::*)() const volatile,
                                              int (S::*)() const volatile&>());
static_assert(
    !check_equality_comparable_with<int (S::*)() const volatile,
                                    int (S::*)() const volatile & noexcept>());
static_assert(!check_equality_comparable_with<int (S::*)() const volatile,
                                              int (S::*)() &&>());
static_assert(!check_equality_comparable_with < int (S::*)() const volatile,
              int (S::*)() && noexcept > ());
static_assert(!check_equality_comparable_with<int (S::*)() const volatile,
                                              int (S::*)() const&&>());
static_assert(!check_equality_comparable_with < int (S::*)() const volatile,
              int (S::*)() const&& noexcept > ());
static_assert(!check_equality_comparable_with<int (S::*)() const volatile,
                                              int (S::*)() volatile&&>());
static_assert(!check_equality_comparable_with < int (S::*)() const volatile,
              int (S::*)() volatile&& noexcept > ());
static_assert(!check_equality_comparable_with<int (S::*)() const volatile,
                                              int (S::*)() const volatile&&>());
static_assert(!check_equality_comparable_with < int (S::*)() const volatile,
              int (S::*)() const volatile&& noexcept > ());

static_assert(
    check_equality_comparable_with<int (S::*)() const volatile noexcept,
                                   int (S::*)() const volatile noexcept>());
static_assert(!check_equality_comparable_with<
              int (S::*)() const volatile noexcept, int (S::*)() &>());
static_assert(!check_equality_comparable_with<
              int (S::*)() const volatile noexcept, int (S::*)() & noexcept>());
static_assert(!check_equality_comparable_with<
              int (S::*)() const volatile noexcept, int (S::*)() const&>());
static_assert(
    !check_equality_comparable_with<int (S::*)() const volatile noexcept,
                                    int (S::*)() const & noexcept>());
static_assert(!check_equality_comparable_with<
              int (S::*)() const volatile noexcept, int (S::*)() volatile&>());
static_assert(
    !check_equality_comparable_with<int (S::*)() const volatile noexcept,
                                    int (S::*)() volatile & noexcept>());
static_assert(
    !check_equality_comparable_with<int (S::*)() const volatile noexcept,
                                    int (S::*)() const volatile&>());
static_assert(
    !check_equality_comparable_with<int (S::*)() const volatile noexcept,
                                    int (S::*)() const volatile & noexcept>());
static_assert(!check_equality_comparable_with<
              int (S::*)() const volatile noexcept, int (S::*)() &&>());
static_assert(!check_equality_comparable_with < int (S::*)()
                                                    const volatile noexcept,
              int (S::*)() && noexcept > ());
static_assert(!check_equality_comparable_with<
              int (S::*)() const volatile noexcept, int (S::*)() const&&>());
static_assert(!check_equality_comparable_with < int (S::*)()
                                                    const volatile noexcept,
              int (S::*)() const&& noexcept > ());
static_assert(!check_equality_comparable_with<
              int (S::*)() const volatile noexcept, int (S::*)() volatile&&>());
static_assert(!check_equality_comparable_with < int (S::*)()
                                                    const volatile noexcept,
              int (S::*)() volatile&& noexcept > ());
static_assert(
    !check_equality_comparable_with<int (S::*)() const volatile noexcept,
                                    int (S::*)() const volatile&&>());
static_assert(!check_equality_comparable_with < int (S::*)()
                                                    const volatile noexcept,
              int (S::*)() const volatile&& noexcept > ());

static_assert(check_equality_comparable_with<int (S::*)() &, int (S::*)() &>());
static_assert(
    check_equality_comparable_with<int (S::*)() &, int (S::*)() & noexcept>());
static_assert(
    !check_equality_comparable_with<int (S::*)() &, int (S::*)() const&>());
static_assert(!check_equality_comparable_with<int (S::*)() &,
                                              int (S::*)() const & noexcept>());
static_assert(
    !check_equality_comparable_with<int (S::*)() &, int (S::*)() volatile&>());
static_assert(!check_equality_comparable_with<
              int (S::*)() &, int (S::*)() volatile & noexcept>());
static_assert(!check_equality_comparable_with<int (S::*)() &,
                                              int (S::*)() const volatile&>());
static_assert(!check_equality_comparable_with<
              int (S::*)() &, int (S::*)() const volatile & noexcept>());
static_assert(
    !check_equality_comparable_with<int (S::*)() &, int (S::*)() &&>());
static_assert(!check_equality_comparable_with < int (S::*)() &,
              int (S::*)() && noexcept > ());
static_assert(
    !check_equality_comparable_with<int (S::*)() &, int (S::*)() const&&>());
static_assert(!check_equality_comparable_with < int (S::*)() &,
              int (S::*)() const&& noexcept > ());
static_assert(
    !check_equality_comparable_with<int (S::*)() &, int (S::*)() volatile&&>());
static_assert(!check_equality_comparable_with < int (S::*)() &,
              int (S::*)() volatile&& noexcept > ());
static_assert(!check_equality_comparable_with<int (S::*)() &,
                                              int (S::*)() const volatile&&>());
static_assert(!check_equality_comparable_with < int (S::*)() &,
              int (S::*)() const volatile&& noexcept > ());

static_assert(check_equality_comparable_with<int (S::*)() & noexcept,
                                             int (S::*)() & noexcept>());
static_assert(!check_equality_comparable_with<int (S::*)() & noexcept,
                                              int (S::*)() const&>());
static_assert(!check_equality_comparable_with<int (S::*)() & noexcept,
                                              int (S::*)() const & noexcept>());
static_assert(!check_equality_comparable_with<int (S::*)() & noexcept,
                                              int (S::*)() volatile&>());
static_assert(!check_equality_comparable_with<
              int (S::*)() & noexcept, int (S::*)() volatile & noexcept>());
static_assert(!check_equality_comparable_with<int (S::*)() & noexcept,
                                              int (S::*)() const volatile&>());
static_assert(
    !check_equality_comparable_with<int (S::*)() & noexcept,
                                    int (S::*)() const volatile & noexcept>());
static_assert(!check_equality_comparable_with<int (S::*)() & noexcept,
                                              int (S::*)() &&>());
static_assert(!check_equality_comparable_with < int (S::*)() & noexcept,
              int (S::*)() && noexcept > ());
static_assert(!check_equality_comparable_with<int (S::*)() & noexcept,
                                              int (S::*)() const&&>());
static_assert(!check_equality_comparable_with < int (S::*)() & noexcept,
              int (S::*)() const&& noexcept > ());
static_assert(!check_equality_comparable_with<int (S::*)() & noexcept,
                                              int (S::*)() volatile&&>());
static_assert(!check_equality_comparable_with < int (S::*)() & noexcept,
              int (S::*)() volatile&& noexcept > ());
static_assert(!check_equality_comparable_with<int (S::*)() & noexcept,
                                              int (S::*)() const volatile&&>());
static_assert(!check_equality_comparable_with < int (S::*)() & noexcept,
              int (S::*)() const volatile&& noexcept > ());

static_assert(
    check_equality_comparable_with<int (S::*)() const&, int (S::*)() const&>());
static_assert(check_equality_comparable_with<int (S::*)() const&,
                                             int (S::*)() const & noexcept>());
static_assert(!check_equality_comparable_with<int (S::*)() const&,
                                              int (S::*)() volatile&>());
static_assert(!check_equality_comparable_with<
              int (S::*)() const&, int (S::*)() volatile & noexcept>());
static_assert(!check_equality_comparable_with<int (S::*)() const&,
                                              int (S::*)() const volatile&>());
static_assert(!check_equality_comparable_with<
              int (S::*)() const&, int (S::*)() const volatile & noexcept>());
static_assert(
    !check_equality_comparable_with<int (S::*)() const&, int (S::*)() &&>());
static_assert(!check_equality_comparable_with < int (S::*)() const&,
              int (S::*)() && noexcept > ());
static_assert(!check_equality_comparable_with<int (S::*)() const&,
                                              int (S::*)() const&&>());
static_assert(!check_equality_comparable_with < int (S::*)() const&,
              int (S::*)() const&& noexcept > ());
static_assert(!check_equality_comparable_with<int (S::*)() const&,
                                              int (S::*)() volatile&&>());
static_assert(!check_equality_comparable_with < int (S::*)() const&,
              int (S::*)() volatile&& noexcept > ());
static_assert(!check_equality_comparable_with<int (S::*)() const&,
                                              int (S::*)() const volatile&&>());
static_assert(!check_equality_comparable_with < int (S::*)() const&,
              int (S::*)() const volatile&& noexcept > ());

static_assert(check_equality_comparable_with<int (S::*)() const & noexcept,
                                             int (S::*)() const & noexcept>());
static_assert(!check_equality_comparable_with<int (S::*)() const & noexcept,
                                              int (S::*)() volatile&>());
static_assert(
    !check_equality_comparable_with<int (S::*)() const & noexcept,
                                    int (S::*)() volatile & noexcept>());
static_assert(!check_equality_comparable_with<int (S::*)() const & noexcept,
                                              int (S::*)() const volatile&>());
static_assert(
    !check_equality_comparable_with<int (S::*)() const & noexcept,
                                    int (S::*)() const volatile & noexcept>());
static_assert(!check_equality_comparable_with<int (S::*)() const & noexcept,
                                              int (S::*)() &&>());
static_assert(!check_equality_comparable_with < int (S::*)() const& noexcept,
              int (S::*)() && noexcept > ());
static_assert(!check_equality_comparable_with<int (S::*)() const & noexcept,
                                              int (S::*)() const&&>());
static_assert(!check_equality_comparable_with < int (S::*)() const& noexcept,
              int (S::*)() const&& noexcept > ());
static_assert(!check_equality_comparable_with<int (S::*)() const & noexcept,
                                              int (S::*)() volatile&&>());
static_assert(!check_equality_comparable_with < int (S::*)() const& noexcept,
              int (S::*)() volatile&& noexcept > ());
static_assert(!check_equality_comparable_with<int (S::*)() const & noexcept,
                                              int (S::*)() const volatile&&>());
static_assert(!check_equality_comparable_with < int (S::*)() const& noexcept,
              int (S::*)() const volatile&& noexcept > ());

static_assert(check_equality_comparable_with<int (S::*)() volatile&,
                                             int (S::*)() volatile&>());
static_assert(check_equality_comparable_with<
              int (S::*)() volatile&, int (S::*)() volatile & noexcept>());
static_assert(!check_equality_comparable_with<int (S::*)() volatile&,
                                              int (S::*)() const volatile&>());
static_assert(
    !check_equality_comparable_with<int (S::*)() volatile&,
                                    int (S::*)() const volatile & noexcept>());
static_assert(
    !check_equality_comparable_with<int (S::*)() volatile&, int (S::*)() &&>());
static_assert(!check_equality_comparable_with < int (S::*)() volatile&,
              int (S::*)() && noexcept > ());
static_assert(!check_equality_comparable_with<int (S::*)() volatile&,
                                              int (S::*)() const&&>());
static_assert(!check_equality_comparable_with < int (S::*)() volatile&,
              int (S::*)() const&& noexcept > ());
static_assert(!check_equality_comparable_with<int (S::*)() volatile&,
                                              int (S::*)() volatile&&>());
static_assert(!check_equality_comparable_with < int (S::*)() volatile&,
              int (S::*)() volatile&& noexcept > ());
static_assert(!check_equality_comparable_with<int (S::*)() volatile&,
                                              int (S::*)() const volatile&&>());
static_assert(!check_equality_comparable_with < int (S::*)() volatile&,
              int (S::*)() const volatile&& noexcept > ());

static_assert(
    check_equality_comparable_with<int (S::*)() volatile & noexcept,
                                   int (S::*)() volatile & noexcept>());
static_assert(!check_equality_comparable_with<int (S::*)() volatile & noexcept,
                                              int (S::*)() const volatile&>());
static_assert(
    !check_equality_comparable_with<int (S::*)() volatile & noexcept,
                                    int (S::*)() const volatile & noexcept>());
static_assert(!check_equality_comparable_with<int (S::*)() volatile & noexcept,
                                              int (S::*)() &&>());
static_assert(!check_equality_comparable_with < int (S::*)() volatile& noexcept,
              int (S::*)() && noexcept > ());
static_assert(!check_equality_comparable_with<int (S::*)() volatile & noexcept,
                                              int (S::*)() const&&>());
static_assert(!check_equality_comparable_with < int (S::*)() volatile& noexcept,
              int (S::*)() const&& noexcept > ());
static_assert(!check_equality_comparable_with<int (S::*)() volatile & noexcept,
                                              int (S::*)() volatile&&>());
static_assert(!check_equality_comparable_with < int (S::*)() volatile& noexcept,
              int (S::*)() volatile&& noexcept > ());
static_assert(!check_equality_comparable_with<int (S::*)() volatile & noexcept,
                                              int (S::*)() const volatile&&>());
static_assert(!check_equality_comparable_with < int (S::*)() volatile& noexcept,
              int (S::*)() const volatile&& noexcept > ());

static_assert(check_equality_comparable_with<int (S::*)() const volatile&,
                                             int (S::*)() const volatile&>());
static_assert(
    check_equality_comparable_with<int (S::*)() const volatile&,
                                   int (S::*)() const volatile & noexcept>());
static_assert(!check_equality_comparable_with<int (S::*)() const volatile&,
                                              int (S::*)() &&>());
static_assert(!check_equality_comparable_with < int (S::*)() const volatile&,
              int (S::*)() && noexcept > ());
static_assert(!check_equality_comparable_with<int (S::*)() const volatile&,
                                              int (S::*)() const&&>());
static_assert(!check_equality_comparable_with < int (S::*)() const volatile&,
              int (S::*)() const&& noexcept > ());
static_assert(!check_equality_comparable_with<int (S::*)() const volatile&,
                                              int (S::*)() volatile&&>());
static_assert(!check_equality_comparable_with < int (S::*)() const volatile&,
              int (S::*)() volatile&& noexcept > ());
static_assert(!check_equality_comparable_with<int (S::*)() const volatile&,
                                              int (S::*)() const volatile&&>());
static_assert(!check_equality_comparable_with < int (S::*)() const volatile&,
              int (S::*)() const volatile&& noexcept > ());

static_assert(
    check_equality_comparable_with<int (S::*)() const volatile & noexcept,
                                   int (S::*)() const volatile & noexcept>());
static_assert(!check_equality_comparable_with<
              int (S::*)() const volatile & noexcept, int (S::*)() &&>());
static_assert(!check_equality_comparable_with < int (S::*)()
                                                    const volatile& noexcept,
              int (S::*)() && noexcept > ());
static_assert(!check_equality_comparable_with<
              int (S::*)() const volatile & noexcept, int (S::*)() const&&>());
static_assert(!check_equality_comparable_with < int (S::*)()
                                                    const volatile& noexcept,
              int (S::*)() const&& noexcept > ());
static_assert(
    !check_equality_comparable_with<int (S::*)() const volatile & noexcept,
                                    int (S::*)() volatile&&>());
static_assert(!check_equality_comparable_with < int (S::*)()
                                                    const volatile& noexcept,
              int (S::*)() volatile&& noexcept > ());
static_assert(
    !check_equality_comparable_with<int (S::*)() const volatile & noexcept,
                                    int (S::*)() const volatile&&>());
static_assert(!check_equality_comparable_with < int (S::*)()
                                                    const volatile& noexcept,
              int (S::*)() const volatile&& noexcept > ());

static_assert(
    check_equality_comparable_with<int (S::*)() &&, int (S::*)() &&>());
static_assert(check_equality_comparable_with<int (S::*)() &&,
                                             int (S::*)() && noexcept>());
static_assert(
    !check_equality_comparable_with<int (S::*)() &&, int (S::*)() const&&>());
static_assert(!check_equality_comparable_with < int (S::*)() &&,
              int (S::*)() const&& noexcept > ());
static_assert(!check_equality_comparable_with<int (S::*)() &&,
                                              int (S::*)() volatile&&>());
static_assert(!check_equality_comparable_with < int (S::*)() &&,
              int (S::*)() volatile&& noexcept > ());
static_assert(!check_equality_comparable_with<int (S::*)() &&,
                                              int (S::*)() const volatile&&>());
static_assert(!check_equality_comparable_with < int (S::*)() &&,
              int (S::*)() const volatile&& noexcept > ());

static_assert(check_equality_comparable_with<int (S::*)() && noexcept,
                                             int (S::*)() && noexcept>());
static_assert(!check_equality_comparable_with < int (S::*)() && noexcept,
              int (S::*)() const&& > ());
static_assert(!check_equality_comparable_with < int (S::*)() && noexcept,
              int (S::*)() const&& noexcept > ());
static_assert(!check_equality_comparable_with < int (S::*)() && noexcept,
              int (S::*)() volatile&& > ());
static_assert(!check_equality_comparable_with < int (S::*)() && noexcept,
              int (S::*)() volatile&& noexcept > ());
static_assert(!check_equality_comparable_with < int (S::*)() && noexcept,
              int (S::*)() const volatile&& > ());
static_assert(!check_equality_comparable_with < int (S::*)() && noexcept,
              int (S::*)() const volatile&& noexcept > ());

static_assert(check_equality_comparable_with<int (S::*)() const&&,
                                             int (S::*)() const&&>());
static_assert(check_equality_comparable_with<int (S::*)() const&&,
                                             int (S::*)() const && noexcept>());
static_assert(!check_equality_comparable_with<int (S::*)() const&&,
                                              int (S::*)() volatile&&>());
static_assert(!check_equality_comparable_with < int (S::*)() const&&,
              int (S::*)() volatile&& noexcept > ());
static_assert(!check_equality_comparable_with<int (S::*)() const&&,
                                              int (S::*)() const volatile&&>());
static_assert(!check_equality_comparable_with < int (S::*)() const&&,
              int (S::*)() const volatile&& noexcept > ());

static_assert(check_equality_comparable_with<int (S::*)() const && noexcept,
                                             int (S::*)() const && noexcept>());
static_assert(!check_equality_comparable_with < int (S::*)() const&& noexcept,
              int (S::*)() volatile&& > ());
static_assert(!check_equality_comparable_with < int (S::*)() const&& noexcept,
              int (S::*)() volatile&& noexcept > ());
static_assert(!check_equality_comparable_with < int (S::*)() const&& noexcept,
              int (S::*)() const volatile&& > ());
static_assert(!check_equality_comparable_with < int (S::*)() const&& noexcept,
              int (S::*)() const volatile&& noexcept > ());

static_assert(check_equality_comparable_with<int (S::*)() volatile&&,
                                             int (S::*)() volatile&&>());
static_assert(check_equality_comparable_with<
              int (S::*)() volatile&&, int (S::*)() volatile && noexcept>());
static_assert(!check_equality_comparable_with<int (S::*)() volatile&&,
                                              int (S::*)() const volatile&&>());
static_assert(!check_equality_comparable_with < int (S::*)() volatile&&,
              int (S::*)() const volatile&& noexcept > ());

static_assert(
    check_equality_comparable_with<int (S::*)() volatile && noexcept,
                                   int (S::*)() volatile && noexcept>());
static_assert(!check_equality_comparable_with <
                  int (S::*)() volatile&& noexcept,
              int (S::*)() const volatile&& > ());
static_assert(!check_equality_comparable_with <
                  int (S::*)() volatile&& noexcept,
              int (S::*)() const volatile&& noexcept > ());

static_assert(check_equality_comparable_with<int (S::*)() const volatile&&,
                                             int (S::*)() const volatile&&>());
static_assert(
    check_equality_comparable_with<int (S::*)() const volatile&&,
                                   int (S::*)() const volatile && noexcept>());
static_assert(
    check_equality_comparable_with<int (S::*)() const volatile && noexcept,
                                   int (S::*)() const volatile && noexcept>());

static_assert(!check_equality_comparable_with<std::nullptr_t, int>());
static_assert(check_equality_comparable_with<std::nullptr_t, int*>());
static_assert(check_equality_comparable_with<std::nullptr_t, int[5]>());
static_assert(check_equality_comparable_with<std::nullptr_t, int (*)()>());
static_assert(check_equality_comparable_with<std::nullptr_t, int (&)()>());
static_assert(check_equality_comparable_with<std::nullptr_t, int (S::*)()>());
static_assert(
    check_equality_comparable_with<std::nullptr_t, int (S::*)() noexcept>());
static_assert(
    check_equality_comparable_with<std::nullptr_t, int (S::*)() const>());
static_assert(check_equality_comparable_with<std::nullptr_t,
                                             int (S::*)() const noexcept>());
static_assert(
    check_equality_comparable_with<std::nullptr_t, int (S::*)() volatile>());
static_assert(check_equality_comparable_with<std::nullptr_t,
                                             int (S::*)() volatile noexcept>());
static_assert(check_equality_comparable_with<std::nullptr_t,
                                             int (S::*)() const volatile>());
static_assert(check_equality_comparable_with<
              std::nullptr_t, int (S::*)() const volatile noexcept>());
static_assert(check_equality_comparable_with<std::nullptr_t, int (S::*)() &>());
static_assert(
    check_equality_comparable_with<std::nullptr_t, int (S::*)() & noexcept>());
static_assert(
    check_equality_comparable_with<std::nullptr_t, int (S::*)() const&>());
static_assert(check_equality_comparable_with<std::nullptr_t,
                                             int (S::*)() const & noexcept>());
static_assert(
    check_equality_comparable_with<std::nullptr_t, int (S::*)() volatile&>());
static_assert(check_equality_comparable_with<
              std::nullptr_t, int (S::*)() volatile & noexcept>());
static_assert(check_equality_comparable_with<std::nullptr_t,
                                             int (S::*)() const volatile&>());
static_assert(check_equality_comparable_with<
              std::nullptr_t, int (S::*)() const volatile & noexcept>());
static_assert(
    check_equality_comparable_with<std::nullptr_t, int (S::*)() &&>());
static_assert(
    check_equality_comparable_with<std::nullptr_t, int (S::*)() && noexcept>());
static_assert(
    check_equality_comparable_with<std::nullptr_t, int (S::*)() const&&>());
static_assert(check_equality_comparable_with<std::nullptr_t,
                                             int (S::*)() const && noexcept>());
static_assert(
    check_equality_comparable_with<std::nullptr_t, int (S::*)() volatile&&>());
static_assert(check_equality_comparable_with<
              std::nullptr_t, int (S::*)() volatile && noexcept>());
static_assert(check_equality_comparable_with<std::nullptr_t,
                                             int (S::*)() const volatile&&>());
static_assert(check_equality_comparable_with<
              std::nullptr_t, int (S::*)() const volatile && noexcept>());

static_assert(!std::equality_comparable_with<void, int>);
static_assert(!std::equality_comparable_with<void, int*>);
static_assert(!std::equality_comparable_with<void, std::nullptr_t>);
static_assert(!std::equality_comparable_with<void, int[5]>);
static_assert(!std::equality_comparable_with<void, int (*)()>);
static_assert(!std::equality_comparable_with<void, int (&)()>);
static_assert(!std::equality_comparable_with<void, int S::*>);
static_assert(!std::equality_comparable_with<void, int (S::*)()>);
static_assert(!std::equality_comparable_with<void, int (S::*)() noexcept>);
static_assert(!std::equality_comparable_with<void, int (S::*)() const>);
static_assert(
    !std::equality_comparable_with<void, int (S::*)() const noexcept>);
static_assert(!std::equality_comparable_with<void, int (S::*)() volatile>);
static_assert(
    !std::equality_comparable_with<void, int (S::*)() volatile noexcept>);
static_assert(
    !std::equality_comparable_with<void, int (S::*)() const volatile>);
static_assert(
    !std::equality_comparable_with<void, int (S::*)() const volatile noexcept>);
static_assert(!std::equality_comparable_with<void, int (S::*)() &>);
static_assert(!std::equality_comparable_with<void, int (S::*)() & noexcept>);
static_assert(!std::equality_comparable_with<void, int (S::*)() const&>);
static_assert(
    !std::equality_comparable_with<void, int (S::*)() const & noexcept>);
static_assert(!std::equality_comparable_with<void, int (S::*)() volatile&>);
static_assert(
    !std::equality_comparable_with<void, int (S::*)() volatile & noexcept>);
static_assert(
    !std::equality_comparable_with<void, int (S::*)() const volatile&>);
static_assert(!std::equality_comparable_with<void, int (S::*)() const volatile &
                                                       noexcept>);
static_assert(!std::equality_comparable_with<void, int (S::*)() &&>);
static_assert(!std::equality_comparable_with < void,
              int (S::*)() && noexcept >);
static_assert(!std::equality_comparable_with<void, int (S::*)() const&&>);
static_assert(!std::equality_comparable_with < void,
              int (S::*)() const&& noexcept >);
static_assert(!std::equality_comparable_with<void, int (S::*)() volatile&&>);
static_assert(!std::equality_comparable_with < void,
              int (S::*)() volatile&& noexcept >);
static_assert(
    !std::equality_comparable_with<void, int (S::*)() const volatile&&>);
static_assert(!std::equality_comparable_with < void,
              int (S::*)() const volatile&& noexcept >);
} // namespace fundamentals

namespace standard_types {
static_assert(check_equality_comparable_with<std::array<int, 10>,
                                             std::array<int, 10> >());
static_assert(!check_equality_comparable_with<std::array<int, 10>,
                                              std::array<double, 10> >());
static_assert(
    check_equality_comparable_with<std::deque<int>, std::deque<int> >());
static_assert(
    !check_equality_comparable_with<std::deque<int>, std::vector<int> >());
static_assert(check_equality_comparable_with<std::forward_list<int>,
                                             std::forward_list<int> >());
static_assert(!check_equality_comparable_with<std::forward_list<int>,
                                              std::vector<int> >());
static_assert(
    check_equality_comparable_with<std::list<int>, std::list<int> >());
static_assert(
    !check_equality_comparable_with<std::list<int>, std::vector<int> >());

#ifndef TEST_HAS_NO_THREADS
static_assert(!check_equality_comparable_with<std::lock_guard<std::mutex>,
                                              std::lock_guard<std::mutex> >());
static_assert(!check_equality_comparable_with<std::lock_guard<std::mutex>,
                                              std::vector<int> >());
static_assert(!check_equality_comparable_with<std::mutex, std::mutex>());
static_assert(!check_equality_comparable_with<std::mutex, std::vector<int> >());
#endif

static_assert(check_equality_comparable_with<std::map<int, void*>,
                                             std::map<int, void*> >());
static_assert(
    !check_equality_comparable_with<std::map<int, void*>, std::vector<int> >());
static_assert(
    check_equality_comparable_with<std::optional<std::vector<int> >,
                                   std::optional<std::vector<int> > >());
static_assert(check_equality_comparable_with<std::optional<std::vector<int> >,
                                             std::vector<int> >());
static_assert(
    check_equality_comparable_with<std::vector<int>, std::vector<int> >());
static_assert(!check_equality_comparable_with<std::vector<int>, int>());
} // namespace standard_types

namespace types_fit_for_purpose {
static_assert(
    check_equality_comparable_with<cxx20_member_eq, cxx20_member_eq>());
static_assert(
    check_equality_comparable_with<cxx20_friend_eq, cxx20_friend_eq>());
static_assert(
    !check_equality_comparable_with<cxx20_member_eq, cxx20_friend_eq>());

static_assert(check_equality_comparable_with<member_three_way_comparable,
                                             member_three_way_comparable>());
static_assert(check_equality_comparable_with<friend_three_way_comparable,
                                             friend_three_way_comparable>());
static_assert(!check_equality_comparable_with<member_three_way_comparable,
                                              friend_three_way_comparable>());

static_assert(
    check_equality_comparable_with<explicit_operators, explicit_operators>());
static_assert(check_equality_comparable_with<equality_comparable_with_ec1,
                                             equality_comparable_with_ec1>());
static_assert(check_equality_comparable_with<different_return_types,
                                             different_return_types>());
static_assert(check_equality_comparable_with<explicit_operators,
                                             equality_comparable_with_ec1>());
static_assert(check_equality_comparable_with<explicit_operators,
                                             different_return_types>());

static_assert(check_equality_comparable_with<one_way_eq, one_way_eq>());
static_assert(
    std::common_reference_with<one_way_eq const&, explicit_operators const&>);
static_assert(
    !check_equality_comparable_with<one_way_eq, explicit_operators>());

static_assert(check_equality_comparable_with<one_way_ne, one_way_ne>());
static_assert(
    std::common_reference_with<one_way_ne const&, explicit_operators const&>);
static_assert(
    !check_equality_comparable_with<one_way_ne, explicit_operators>());
} // namespace types_fit_for_purpose