// -*- C++ -*-
//===----------------------------------------------------------------------===//
//
// 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
//
//===----------------------------------------------------------------------===//

// REQUIRES: c++experimental
// UNSUPPORTED: c++98, c++03

// <experimental/unordered_set>

// namespace std { namespace experimental { namespace pmr {
// template <class V, class H = hash<V>, class P = equal_to<V> >
// using unordered_set =
//     ::std::unordered_set<V, H, P, polymorphic_allocator<V>>
//
// template <class V,  class H = hash<V>, class P = equal_to<V> >
// using unordered_multiset =
//     ::std::unordered_multiset<V, H, P, polymorphic_allocator<V>>
//
// }}} // namespace std::experimental::pmr

#include <experimental/unordered_set>
#include <experimental/memory_resource>
#include <type_traits>
#include <cassert>

namespace pmr = std::experimental::pmr;

template <class T>
struct MyHash : std::hash<T> {};

template <class T>
struct MyPred : std::equal_to<T> {};

int main(int, char**)
{
    using V = char;
    using DH = std::hash<V>;
    using MH = MyHash<V>;
    using DP = std::equal_to<V>;
    using MP = MyPred<V>;
    {
        using StdSet = std::unordered_set<V, DH, DP, pmr::polymorphic_allocator<V>>;
        using PmrSet = pmr::unordered_set<V>;
        static_assert(std::is_same<StdSet, PmrSet>::value, "");
    }
    {
        using StdSet = std::unordered_set<V, MH, DP, pmr::polymorphic_allocator<V>>;
        using PmrSet = pmr::unordered_set<V, MH>;
        static_assert(std::is_same<StdSet, PmrSet>::value, "");
    }
    {
        using StdSet = std::unordered_set<V, MH, MP, pmr::polymorphic_allocator<V>>;
        using PmrSet = pmr::unordered_set<V, MH, MP>;
        static_assert(std::is_same<StdSet, PmrSet>::value, "");
    }
    {
        pmr::unordered_set<int> m;
        assert(m.get_allocator().resource() == pmr::get_default_resource());
    }
    {
        using StdSet = std::unordered_multiset<V, DH, DP, pmr::polymorphic_allocator<V>>;
        using PmrSet = pmr::unordered_multiset<V>;
        static_assert(std::is_same<StdSet, PmrSet>::value, "");
    }
    {
        using StdSet = std::unordered_multiset<V, MH, DP, pmr::polymorphic_allocator<V>>;
        using PmrSet = pmr::unordered_multiset<V, MH>;
        static_assert(std::is_same<StdSet, PmrSet>::value, "");
    }
    {
        using StdSet = std::unordered_multiset<V, MH, MP, pmr::polymorphic_allocator<V>>;
        using PmrSet = pmr::unordered_multiset<V, MH, MP>;
        static_assert(std::is_same<StdSet, PmrSet>::value, "");
    }
    {
        pmr::unordered_multiset<int> m;
        assert(m.get_allocator().resource() == pmr::get_default_resource());
    }

  return 0;
}