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// Copyright (C) 2020 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-options "-std=gnu++2a" }
// { dg-do compile { target c++2a } }
#include <iterator>
template<int>
struct Iter
{
using iterator_category = std::random_access_iterator_tag;
using value_type = int;
using pointer = int*;
using reference = int&;
using difference_type = std::ptrdiff_t;
Iter();
Iter& operator++();
Iter operator++(int);
Iter& operator--();
Iter operator--(int);
int& operator*() const;
int* operator->() const;
int& operator[](difference_type) const;
Iter& operator+=(difference_type);
Iter& operator-=(difference_type);
template<int N> friend Iter operator+(Iter<N>, difference_type);
template<int N> friend Iter operator+(difference_type, Iter<N>);
template<int N> friend Iter operator-(Iter<N>, difference_type);
template<int N> friend difference_type operator-(Iter<N>, Iter<N>);
// Define the full set of operators for same-type comparisons
template<int N> friend bool operator==(Iter<N>, Iter<N>); // synthesizes !=
template<int N> friend bool operator<(Iter<N>, Iter<N>);
template<int N> friend bool operator>(Iter<N>, Iter<N>);
template<int N> friend bool operator<=(Iter<N>, Iter<N>);
template<int N> friend bool operator>=(Iter<N>, Iter<N>);
};
static_assert( std::random_access_iterator<Iter<0>> );
int operator==(Iter<0>, long*);
void* operator< (Iter<1>, long*);
bool& operator< (long*, Iter<2>);
using std::move_iterator;
static_assert( std::three_way_comparable<move_iterator<Iter<0>>> );
move_iterator<Iter<0>> l0{Iter<0>()};
move_iterator<Iter<1>> l1{Iter<1>()};
move_iterator<Iter<2>> l2{Iter<2>()};
move_iterator<long*> r{nullptr};
bool b0 = l0 == r;
bool b1 = l0 != r;
bool b2 = l1 < r;
bool b3 = l2 > r;
bool b4 = l2 <= r;
bool b5 = l1 >= r;
template<int N>
concept has_eq
= requires (move_iterator<Iter<N>> l, move_iterator<long*> r)
{ l == r; };
template<int N>
concept has_ne
= requires (move_iterator<Iter<N>> l, move_iterator<long*> r)
{ l != r; };
template<int N>
concept has_lt
= requires (move_iterator<Iter<N>> l, move_iterator<long*> r)
{ l < r; };
template<int N>
concept has_gt
= requires (move_iterator<Iter<N>> l, move_iterator<long*> r)
{ l > r; };
template<int N>
concept has_le
= requires (move_iterator<Iter<N>> l, move_iterator<long*> r)
{ l <= r; };
template<int N>
concept has_ge
= requires (move_iterator<Iter<N>> l, move_iterator<long*> r)
{ l >= r; };
static_assert( has_eq<0> );
static_assert( ! has_eq<1> );
static_assert( ! has_eq<2> );
static_assert( has_ne<0> ); // uses synthesized operator!=
static_assert( ! has_ne<1> );
static_assert( ! has_ne<2> );
static_assert( ! has_lt<0> );
static_assert( has_lt<1> );
static_assert( ! has_lt<2> );
static_assert( ! has_gt<0> );
static_assert( ! has_gt<1> );
static_assert( has_gt<2> );
static_assert( ! has_le<0> );
static_assert( ! has_le<1> );
static_assert( has_le<2> );
static_assert( ! has_ge<0> );
static_assert( has_ge<1> );
static_assert( ! has_ge<2> );
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