text: //===----------------------------------------------------------------------===//
  //
  // 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
  
  // <unordered_set>
  
  // class unordered_set
  
  // node_type extract(const_iterator);
  
  #include <unordered_set>
  #include "test_macros.h"
  #include "min_allocator.h"
  #include "Counter.h"
  
  template <class Container>
  void test(Container& c)
  {
      size_t sz = c.size();
  
      for (auto first = c.cbegin(); first != c.cend();)
      {
          auto key_value = *first;
          typename Container::node_type t = c.extract(first++);
          --sz;
          assert(t.value() == key_value);
          assert(t.get_allocator() == c.get_allocator());
          assert(sz == c.size());
      }
  
      assert(c.size() == 0);
  }
  
  int main(int, char**)
  {
      {
          using set_type = std::unordered_set<int>;
          set_type m = {1, 2, 3, 4, 5, 6};
          test(m);
      }
  
      {
          std::unordered_set<Counter<int>> m = {1, 2, 3, 4, 5, 6};
          assert(Counter_base::gConstructed == 6);
          test(m);
          assert(Counter_base::gConstructed == 0);
      }
  
      {
          using min_alloc_set = std::unordered_set<int, std::hash<int>, std::equal_to<int>, min_allocator<int>>;
          min_alloc_set m = {1, 2, 3, 4, 5, 6};
          test(m);
      }
  
    return 0;
  }
  