// Copyright (C) 2019-2025 Free Software Foundation, Inc.
//
// This file is part of the GNU ISO C++ Library.  This library is free
// software; you can redistribute it and/or modify it under the
// terms of the GNU General Public License as published by the
// Free Software Foundation; either version 3, or (at your option)
// any later version.

// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.

// You should have received a copy of the GNU General Public License along
// with this library; see the file COPYING3.  If not see
// <http://www.gnu.org/licenses/>.

// { dg-do compile { target c++20 } }

#include <concepts>

static_assert( std::regular<int> );
static_assert( std::regular<int*> );
static_assert( ! std::regular<int&> );
static_assert( ! std::regular<void> );
static_assert( ! std::regular<void()> );
static_assert( ! std::regular<void() noexcept> );
static_assert( ! std::regular<void() const> );

struct Trivial { };
static_assert( ! std::regular<Trivial> );

struct NotTrivial
{
  NotTrivial() { }
  ~NotTrivial() { }
};
static_assert( ! std::regular<NotTrivial> );

struct NotDefaultConstructible
{
  NotDefaultConstructible(int) { }
};
static_assert( ! std::regular<NotDefaultConstructible> );

struct HasReference
{
  int& ref;
};
static_assert( ! std::regular<HasReference> );

struct HasEq { };
bool operator==(HasEq, HasEq) { return true; }
#ifdef __cpp_impl_three_way_comparison
static_assert( std::regular<HasEq> );
#else
static_assert( ! std::regular<HasEq> );
#endif

struct HasEqNeq { };
bool operator==(HasEqNeq, HasEqNeq) { return true; }
bool operator!=(HasEqNeq, HasEqNeq) { return false; }
static_assert( std::regular<HasEqNeq> );