queue | Explore in Territory

// -*- 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
//
//===----------------------------------------------------------------------===//

#ifndef _LIBCPP_QUEUE
#define _LIBCPP_QUEUE

/*
    queue synopsis

namespace std
{

template <class T, class Container = deque<T>>
class queue
{
public:
    typedef Container                                container_type;
    typedef typename container_type::value_type      value_type;
    typedef typename container_type::reference       reference;
    typedef typename container_type::const_reference const_reference;
    typedef typename container_type::size_type       size_type;

protected:
    container_type c;

public:
    queue() = default;
    ~queue() = default;

    queue(const queue& q) = default;
    queue(queue&& q) = default;

    queue& operator=(const queue& q) = default;
    queue& operator=(queue&& q) = default;

    explicit queue(const container_type& c);
    explicit queue(container_type&& c)
    template<class InputIterator>
        queue(InputIterator first, InputIterator last); // since C++23
    template<container-compatible-range<T> R> queue(from_range_t, R&& rg); // since C++23
    template <class Alloc>
        explicit queue(const Alloc& a);
    template <class Alloc>
        queue(const container_type& c, const Alloc& a);
    template <class Alloc>
        queue(container_type&& c, const Alloc& a);
    template <class Alloc>
        queue(const queue& q, const Alloc& a);
    template <class Alloc>
        queue(queue&& q, const Alloc& a);
    template <class InputIterator, class Alloc>
        queue(InputIterator first, InputIterator last, const Alloc&); // since C++23
    template<container-compatible-range<T> R, class Alloc>
        queue(from_range_t, R&& rg, const Alloc&); // since C++23

    bool      empty() const;
    size_type size() const;

    reference       front();
    const_reference front() const;
    reference       back();
    const_reference back() const;

    void push(const value_type& v);
    void push(value_type&& v);
    template<container-compatible-range<T> R>
      void push_range(R&& rg); // C++23
    template <class... Args> reference emplace(Args&&... args); // reference in C++17
    void pop();

    void swap(queue& q) noexcept(is_nothrow_swappable_v<Container>)
};

template<class Container>
  queue(Container) -> queue<typename Container::value_type, Container>; // C++17

template<class InputIterator>
  queue(InputIterator, InputIterator) -> queue<iter-value-type<InputIterator>>; // since C++23

template<ranges::input_range R>
  queue(from_range_t, R&&) -> queue<ranges::range_value_t<R>>; // since C++23

template<class Container, class Allocator>
  queue(Container, Allocator) -> queue<typename Container::value_type, Container>; // C++17

template<class InputIterator, class Allocator>
  queue(InputIterator, InputIterator, Allocator)
  -> queue<iter-value-type<InputIterator>,
           deque<iter-value-type<InputIterator>, Allocator>>; // since C++23

template<ranges::input_range R, class Allocator>
    queue(from_range_t, R&&, Allocator)
      -> queue<ranges::range_value_t<R>, deque<ranges::range_value_t<R>, Allocator>>; // since C++23

template <class T, class Container>
  bool operator==(const queue<T, Container>& x,const queue<T, Container>& y);

template <class T, class Container>
  bool operator< (const queue<T, Container>& x,const queue<T, Container>& y);

template <class T, class Container>
  bool operator!=(const queue<T, Container>& x,const queue<T, Container>& y);

template <class T, class Container>
  bool operator> (const queue<T, Container>& x,const queue<T, Container>& y);

template <class T, class Container>
  bool operator>=(const queue<T, Container>& x,const queue<T, Container>& y);

template <class T, class Container>
  bool operator<=(const queue<T, Container>& x,const queue<T, Container>& y);

template<class T, three_way_comparable Container>
  compare_three_way_result_t<Container>
    operator<=>(const queue<T, Container>& x, const queue<T, Container>& y);  // since C++20

template <class T, class Container>
  void swap(queue<T, Container>& x, queue<T, Container>& y)
  noexcept(noexcept(x.swap(y)));

template <class T, class Container = vector<T>,
          class Compare = less<typename Container::value_type>>
class priority_queue
{
public:
    typedef Container                                container_type;
    typedef typename container_type::value_type      value_type;
    typedef typename container_type::reference       reference;
    typedef typename container_type::const_reference const_reference;
    typedef typename container_type::size_type       size_type;

protected:
    container_type c;
    Compare comp;

public:
    priority_queue() : priority_queue(Compare()) {} // C++20
    explicit priority_queue(const Compare& x) : priority_queue(x, Container()) {}
    priority_queue(const Compare& x, const Container&);
    explicit priority_queue(const Compare& x = Compare(), Container&& = Container()); // before C++20
    priority_queue(const Compare& x, Container&&); // C++20
    template <class InputIterator>
        priority_queue(InputIterator first, InputIterator last,
                       const Compare& comp = Compare());
    template <class InputIterator>
        priority_queue(InputIterator first, InputIterator last,
                       const Compare& comp, const Container& c);
    template <class InputIterator>
        priority_queue(InputIterator first, InputIterator last,
                       const Compare& comp, Container&& c);
    template <container-compatible-range<T> R>
        priority_queue(from_range_t, R&& rg, const Compare& x = Compare()); // since C++23
    template <class Alloc>
        explicit priority_queue(const Alloc& a);
    template <class Alloc>
        priority_queue(const Compare& comp, const Alloc& a);
    template <class Alloc>
        priority_queue(const Compare& comp, const Container& c,
                       const Alloc& a);
    template <class Alloc>
        priority_queue(const Compare& comp, Container&& c,
                       const Alloc& a);
    template <class InputIterator>
        priority_queue(InputIterator first, InputIterator last,
                       const Alloc& a);
    template <class InputIterator>
        priority_queue(InputIterator first, InputIterator last,
                       const Compare& comp, const Alloc& a);
    template <class InputIterator>
        priority_queue(InputIterator first, InputIterator last,
                       const Compare& comp, const Container& c, const Alloc& a);
    template <class InputIterator>
        priority_queue(InputIterator first, InputIterator last,
                       const Compare& comp, Container&& c, const Alloc& a);
    template <container-compatible-range<T> R, class Alloc>
      priority_queue(from_range_t, R&& rg, const Compare&, const Alloc&); // since C++23
    template <container-compatible-range<T> R, class Alloc>
      priority_queue(from_range_t, R&& rg, const Alloc&); // since C++23
    template <class Alloc>
        priority_queue(const priority_queue& q, const Alloc& a);
    template <class Alloc>
        priority_queue(priority_queue&& q, const Alloc& a);

    bool            empty() const;
    size_type       size() const;
    const_reference top() const;

    void push(const value_type& v);
    void push(value_type&& v);
    template<container-compatible-range<T> R>
      void push_range(R&& rg); // C++23
    template <class... Args> void emplace(Args&&... args);
    void pop();

    void swap(priority_queue& q)
        noexcept(is_nothrow_swappable_v<Container> &&
                 is_nothrow_swappable_v<Comp>)
};

template <class Compare, class Container>
priority_queue(Compare, Container)
    -> priority_queue<typename Container::value_type, Container, Compare>; // C++17

template<class InputIterator,
         class Compare = less<iter-value-type<InputIterator>>,
         class Container = vector<iter-value-type<InputIterator>>>
priority_queue(InputIterator, InputIterator, Compare = Compare(), Container = Container())
    -> priority_queue<iter-value-type<InputIterator>, Container, Compare>; // C++17

template<ranges::input_range R, class Compare = less<ranges::range_value_t<R>>>
  priority_queue(from_range_t, R&&, Compare = Compare())
    -> priority_queue<ranges::range_value_t<R>, vector<ranges::range_value_t<R>>, Compare>; // C++23

template<class Compare, class Container, class Allocator>
priority_queue(Compare, Container, Allocator)
    -> priority_queue<typename Container::value_type, Container, Compare>; // C++17

template<class InputIterator, class Allocator>
priority_queue(InputIterator, InputIterator, Allocator)
    -> priority_queue<iter-value-type<InputIterator>,
                      vector<iter-value-type<InputIterator>, Allocator>,
                      less<iter-value-type<InputIterator>>>; // C++17

template<class InputIterator, class Compare, class Allocator>
priority_queue(InputIterator, InputIterator, Compare, Allocator)
    -> priority_queue<iter-value-type<InputIterator>,
                      vector<iter-value-type<InputIterator>, Allocator>, Compare>; // C++17

template<class InputIterator, class Compare, class Container, class Allocator>
priority_queue(InputIterator, InputIterator, Compare, Container, Allocator)
    -> priority_queue<typename Container::value_type, Container, Compare>; // C++17

template<ranges::input_range R, class Compare, class Allocator>
  priority_queue(from_range_t, R&&, Compare, Allocator)
    -> priority_queue<ranges::range_value_t<R>, vector<ranges::range_value_t<R>, Allocator>,
                        Compare>; // C++23

template<ranges::input_range R, class Allocator>
  priority_queue(from_range_t, R&&, Allocator)
    -> priority_queue<ranges::range_value_t<R>, vector<ranges::range_value_t<R>, Allocator>>; // C++23

template <class T, class Container, class Compare>
  void swap(priority_queue<T, Container, Compare>& x,
            priority_queue<T, Container, Compare>& y)
            noexcept(noexcept(x.swap(y)));

}  // std

*/

#include <__algorithm/make_heap.h>
#include <__algorithm/pop_heap.h>
#include <__algorithm/push_heap.h>
#include <__algorithm/ranges_copy.h>
#include <__config>
#include <__functional/operations.h>
#include <__fwd/deque.h>
#include <__fwd/queue.h>
#include <__iterator/back_insert_iterator.h>
#include <__iterator/iterator_traits.h>
#include <__memory/uses_allocator.h>
#include <__ranges/access.h>
#include <__ranges/concepts.h>
#include <__ranges/container_compatible_range.h>
#include <__ranges/from_range.h>
#include <__utility/forward.h>
#include <deque>
#include <vector>
#include <version>

// standard-mandated includes

// [queue.syn]
#include <compare>
#include <initializer_list>

#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
#  pragma GCC system_header
#endif

_LIBCPP_PUSH_MACROS
#include <__undef_macros>

_LIBCPP_BEGIN_NAMESPACE_STD

template <class _Tp, class _Container>
_LIBCPP_HIDE_FROM_ABI bool operator==(const queue<_Tp, _Container>& __x, const queue<_Tp, _Container>& __y);

template <class _Tp, class _Container>
_LIBCPP_HIDE_FROM_ABI bool operator<(const queue<_Tp, _Container>& __x, const queue<_Tp, _Container>& __y);

template <class _Tp, class _Container /*= deque<_Tp>*/>
class _LIBCPP_TEMPLATE_VIS queue { … };

#if _LIBCPP_STD_VER >= 17
template <class _Container, class = enable_if_t<!__is_allocator<_Container>::value> >
queue(_Container) -> queue<typename _Container::value_type, _Container>;

template <class _Container,
          class _Alloc,
          class = enable_if_t<!__is_allocator<_Container>::value>,
          class = enable_if_t<uses_allocator<_Container, _Alloc>::value> >
queue(_Container, _Alloc) -> queue<typename _Container::value_type, _Container>;
#endif

#if _LIBCPP_STD_VER >= 23
template <class _InputIterator, __enable_if_t<__has_input_iterator_category<_InputIterator>::value, int> = 0>
queue(_InputIterator, _InputIterator) -> queue<__iter_value_type<_InputIterator>>;

template <ranges::input_range _Range>
queue(from_range_t, _Range&&) -> queue<ranges::range_value_t<_Range>>;

template <class _InputIterator,
          class _Alloc,
          __enable_if_t<__has_input_iterator_category<_InputIterator>::value, int> = 0,
          __enable_if_t<__is_allocator<_Alloc>::value, int>                        = 0>
queue(_InputIterator,
      _InputIterator,
      _Alloc) -> queue<__iter_value_type<_InputIterator>, deque<__iter_value_type<_InputIterator>, _Alloc>>;

template <ranges::input_range _Range, class _Alloc, __enable_if_t<__is_allocator<_Alloc>::value, int> = 0>
queue(from_range_t,
      _Range&&,
      _Alloc) -> queue<ranges::range_value_t<_Range>, deque<ranges::range_value_t<_Range>, _Alloc>>;
#endif

template <class _Tp, class _Container>
inline _LIBCPP_HIDE_FROM_ABI bool operator==(const queue<_Tp, _Container>& __x, const queue<_Tp, _Container>& __y) { … }

template <class _Tp, class _Container>
inline _LIBCPP_HIDE_FROM_ABI bool operator<(const queue<_Tp, _Container>& __x, const queue<_Tp, _Container>& __y) { … }

template <class _Tp, class _Container>
inline _LIBCPP_HIDE_FROM_ABI bool operator!=(const queue<_Tp, _Container>& __x, const queue<_Tp, _Container>& __y) { … }

template <class _Tp, class _Container>
inline _LIBCPP_HIDE_FROM_ABI bool operator>(const queue<_Tp, _Container>& __x, const queue<_Tp, _Container>& __y) { … }

template <class _Tp, class _Container>
inline _LIBCPP_HIDE_FROM_ABI bool operator>=(const queue<_Tp, _Container>& __x, const queue<_Tp, _Container>& __y) { … }

template <class _Tp, class _Container>
inline _LIBCPP_HIDE_FROM_ABI bool operator<=(const queue<_Tp, _Container>& __x, const queue<_Tp, _Container>& __y) { … }

#if _LIBCPP_STD_VER >= 20

template <class _Tp, three_way_comparable _Container>
_LIBCPP_HIDE_FROM_ABI compare_three_way_result_t<_Container>
operator<=>(const queue<_Tp, _Container>& __x, const queue<_Tp, _Container>& __y) { … }

#endif

template <class _Tp, class _Container, __enable_if_t<__is_swappable_v<_Container>, int> = 0>
inline _LIBCPP_HIDE_FROM_ABI void swap(queue<_Tp, _Container>& __x, queue<_Tp, _Container>& __y)
    _NOEXCEPT_(_NOEXCEPT_(__x.swap(__y))) { … }

uses_allocator<queue<_Tp, _Container>, _Alloc>;

template <class _Tp, class _Container, class _Compare>
class _LIBCPP_TEMPLATE_VIS priority_queue { … };

#if _LIBCPP_STD_VER >= 17
template <class _Compare,
          class _Container,
          class = enable_if_t<!__is_allocator<_Compare>::value>,
          class = enable_if_t<!__is_allocator<_Container>::value> >
priority_queue(_Compare, _Container) -> priority_queue<typename _Container::value_type, _Container, _Compare>;

template <class _InputIterator,
          class _Compare   = less<__iter_value_type<_InputIterator>>,
          class _Container = vector<__iter_value_type<_InputIterator>>,
          class            = enable_if_t<__has_input_iterator_category<_InputIterator>::value>,
          class            = enable_if_t<!__is_allocator<_Compare>::value>,
          class            = enable_if_t<!__is_allocator<_Container>::value> >
priority_queue(_InputIterator, _InputIterator, _Compare = _Compare(), _Container = _Container())
    -> priority_queue<__iter_value_type<_InputIterator>, _Container, _Compare>;

template <class _Compare,
          class _Container,
          class _Alloc,
          class = enable_if_t<!__is_allocator<_Compare>::value>,
          class = enable_if_t<!__is_allocator<_Container>::value>,
          class = enable_if_t<uses_allocator<_Container, _Alloc>::value> >
priority_queue(_Compare, _Container, _Alloc) -> priority_queue<typename _Container::value_type, _Container, _Compare>;

template <class _InputIterator,
          class _Allocator,
          class = enable_if_t<__has_input_iterator_category<_InputIterator>::value>,
          class = enable_if_t<__is_allocator<_Allocator>::value> >
priority_queue(_InputIterator, _InputIterator, _Allocator)
    -> priority_queue<__iter_value_type<_InputIterator>,
                      vector<__iter_value_type<_InputIterator>, _Allocator>,
                      less<__iter_value_type<_InputIterator>>>;

template <class _InputIterator,
          class _Compare,
          class _Allocator,
          class = enable_if_t<__has_input_iterator_category<_InputIterator>::value>,
          class = enable_if_t<!__is_allocator<_Compare>::value>,
          class = enable_if_t<__is_allocator<_Allocator>::value> >
priority_queue(_InputIterator, _InputIterator, _Compare, _Allocator)
    -> priority_queue<__iter_value_type<_InputIterator>,
                      vector<__iter_value_type<_InputIterator>, _Allocator>,
                      _Compare>;

template <class _InputIterator,
          class _Compare,
          class _Container,
          class _Alloc,
          class = enable_if_t<__has_input_iterator_category<_InputIterator>::value>,
          class = enable_if_t<!__is_allocator<_Compare>::value>,
          class = enable_if_t<!__is_allocator<_Container>::value>,
          class = enable_if_t<uses_allocator<_Container, _Alloc>::value> >
priority_queue(_InputIterator, _InputIterator, _Compare, _Container, _Alloc)
    -> priority_queue<typename _Container::value_type, _Container, _Compare>;
#endif

#if _LIBCPP_STD_VER >= 23

template <ranges::input_range _Range,
          class _Compare = less<ranges::range_value_t<_Range>>,
          class          = enable_if_t<!__is_allocator<_Compare>::value>>
priority_queue(from_range_t, _Range&&, _Compare = _Compare())
    -> priority_queue<ranges::range_value_t<_Range>, vector<ranges::range_value_t<_Range>>, _Compare>;

template <ranges::input_range _Range,
          class _Compare,
          class _Alloc,
          class = enable_if_t<!__is_allocator<_Compare>::value>,
          class = enable_if_t<__is_allocator<_Alloc>::value>>
priority_queue(from_range_t, _Range&&, _Compare, _Alloc)
    -> priority_queue<ranges::range_value_t<_Range>, vector<ranges::range_value_t<_Range>, _Alloc>, _Compare>;

template <ranges::input_range _Range, class _Alloc, class = enable_if_t<__is_allocator<_Alloc>::value>>
priority_queue(from_range_t, _Range&&, _Alloc)
    -> priority_queue<ranges::range_value_t<_Range>, vector<ranges::range_value_t<_Range>, _Alloc>>;

#endif

template <class _Tp, class _Container, class _Compare>
inline priority_queue<_Tp, _Container, _Compare>::priority_queue(const _Compare& __comp, const container_type& __c)
    : … { … }

#ifndef _LIBCPP_CXX03_LANG

template <class _Tp, class _Container, class _Compare>
inline priority_queue<_Tp, _Container, _Compare>::priority_queue(const value_compare& __comp, container_type&& __c)
    : … { … }

#endif // _LIBCPP_CXX03_LANG

template <class _Tp, class _Container, class _Compare>
template <class _InputIter, __enable_if_t<__has_input_iterator_category<_InputIter>::value, int> >
inline priority_queue<_Tp, _Container, _Compare>::priority_queue(
    _InputIter __f, _InputIter __l, const value_compare& __comp)
    : c(__f, __l), comp(__comp) { … }

template <class _Tp, class _Container, class _Compare>
template <class _InputIter, __enable_if_t<__has_input_iterator_category<_InputIter>::value, int> >
inline priority_queue<_Tp, _Container, _Compare>::priority_queue(
    _InputIter __f, _InputIter __l, const value_compare& __comp, const container_type& __c)
    : c(__c), comp(__comp) { … }

#ifndef _LIBCPP_CXX03_LANG

template <class _Tp, class _Container, class _Compare>
template <class _InputIter, __enable_if_t<__has_input_iterator_category<_InputIter>::value, int> >
inline priority_queue<_Tp, _Container, _Compare>::priority_queue(
    _InputIter __f, _InputIter __l, const value_compare& __comp, container_type&& __c)
    : c(std::move(__c)), comp(__comp) { … }

#endif // _LIBCPP_CXX03_LANG

template <class _Tp, class _Container, class _Compare>
template <class _Alloc, __enable_if_t<uses_allocator<_Container, _Alloc>::value, int> >
inline priority_queue<_Tp, _Container, _Compare>::priority_queue(const _Alloc& __a) : c(__a) { … }

template <class _Tp, class _Container, class _Compare>
template <class _Alloc, __enable_if_t<uses_allocator<_Container, _Alloc>::value, int> >
inline priority_queue<_Tp, _Container, _Compare>::priority_queue(const value_compare& __comp, const _Alloc& __a)
    : c(__a), comp(__comp) { … }

template <class _Tp, class _Container, class _Compare>
template <class _Alloc, __enable_if_t<uses_allocator<_Container, _Alloc>::value, int> >
inline priority_queue<_Tp, _Container, _Compare>::priority_queue(
    const value_compare& __comp, const container_type& __c, const _Alloc& __a)
    : c(__c, __a), comp(__comp) { … }

template <class _Tp, class _Container, class _Compare>
template <class _Alloc, __enable_if_t<uses_allocator<_Container, _Alloc>::value, int> >
inline priority_queue<_Tp, _Container, _Compare>::priority_queue(const priority_queue& __q, const _Alloc& __a)
    : c(__q.c, __a), comp(__q.comp) { … }

#ifndef _LIBCPP_CXX03_LANG

template <class _Tp, class _Container, class _Compare>
template <class _Alloc, __enable_if_t<uses_allocator<_Container, _Alloc>::value, int> >
inline priority_queue<_Tp, _Container, _Compare>::priority_queue(
    const value_compare& __comp, container_type&& __c, const _Alloc& __a)
    : c(std::move(__c), __a), comp(__comp) { … }

template <class _Tp, class _Container, class _Compare>
template <class _Alloc, __enable_if_t<uses_allocator<_Container, _Alloc>::value, int> >
inline priority_queue<_Tp, _Container, _Compare>::priority_queue(priority_queue&& __q, const _Alloc& __a)
    : c(std::move(__q.c), __a), comp(std::move(__q.comp)) { … }

#endif // _LIBCPP_CXX03_LANG

template <class _Tp, class _Container, class _Compare>
template <
    class _InputIter,
    class _Alloc,
    __enable_if_t<__has_input_iterator_category<_InputIter>::value && uses_allocator<_Container, _Alloc>::value, int> >
inline priority_queue<_Tp, _Container, _Compare>::priority_queue(_InputIter __f, _InputIter __l, const _Alloc& __a)
    : c(__f, __l, __a), comp() { … }

template <class _Tp, class _Container, class _Compare>
template <
    class _InputIter,
    class _Alloc,
    __enable_if_t<__has_input_iterator_category<_InputIter>::value && uses_allocator<_Container, _Alloc>::value, int> >
inline priority_queue<_Tp, _Container, _Compare>::priority_queue(
    _InputIter __f, _InputIter __l, const value_compare& __comp, const _Alloc& __a)
    : c(__f, __l, __a), comp(__comp) { … }

template <class _Tp, class _Container, class _Compare>
template <
    class _InputIter,
    class _Alloc,
    __enable_if_t<__has_input_iterator_category<_InputIter>::value && uses_allocator<_Container, _Alloc>::value, int> >
inline priority_queue<_Tp, _Container, _Compare>::priority_queue(
    _InputIter __f, _InputIter __l, const value_compare& __comp, const container_type& __c, const _Alloc& __a)
    : c(__c, __a), comp(__comp) { … }

#ifndef _LIBCPP_CXX03_LANG
template <class _Tp, class _Container, class _Compare>
template <
    class _InputIter,
    class _Alloc,
    __enable_if_t<__has_input_iterator_category<_InputIter>::value && uses_allocator<_Container, _Alloc>::value, int> >
inline priority_queue<_Tp, _Container, _Compare>::priority_queue(
    _InputIter __f, _InputIter __l, const value_compare& __comp, container_type&& __c, const _Alloc& __a)
    : c(std::move(__c), __a), comp(__comp) { … }
#endif // _LIBCPP_CXX03_LANG

template <class _Tp, class _Container, class _Compare>
inline void priority_queue<_Tp, _Container, _Compare>::push(const value_type& __v) { … }

#ifndef _LIBCPP_CXX03_LANG

template <class _Tp, class _Container, class _Compare>
inline void priority_queue<_Tp, _Container, _Compare>::push(value_type&& __v) { … }

template <class _Tp, class _Container, class _Compare>
template <class... _Args>
inline void priority_queue<_Tp, _Container, _Compare>::emplace(_Args&&... __args) { … }

#endif // _LIBCPP_CXX03_LANG

template <class _Tp, class _Container, class _Compare>
inline void priority_queue<_Tp, _Container, _Compare>::pop() { … }

template <class _Tp, class _Container, class _Compare>
inline void priority_queue<_Tp, _Container, _Compare>::swap(priority_queue& __q)
    _NOEXCEPT_(__is_nothrow_swappable_v<container_type>&& __is_nothrow_swappable_v<value_compare>) { … }

template <class _Tp,
          class _Container,
          class _Compare,
          __enable_if_t<__is_swappable_v<_Container> && __is_swappable_v<_Compare>, int> = 0>
inline _LIBCPP_HIDE_FROM_ABI void
swap(priority_queue<_Tp, _Container, _Compare>& __x, priority_queue<_Tp, _Container, _Compare>& __y)
    _NOEXCEPT_(_NOEXCEPT_(__x.swap(__y))) { … }

uses_allocator<priority_queue<_Tp, _Container, _Compare>, _Alloc>;

_LIBCPP_END_NAMESPACE_STD

_LIBCPP_POP_MACROS

#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
#  include <concepts>
#  include <cstdlib>
#  include <functional>
#  include <type_traits>
#endif

#endif // _LIBCPP_QUEUE
chromium/third_party/libc++/src/include/queue
