<boost/unordered/unordered_map.hpp> Synopsis

Defines boost::unordered_map, boost::unordered_multimap and associated functions and alias templates.

namespace boost {
namespace unordered {

  template<class Key,
           class T,
           class Hash = boost::hash<Key>,
           class Pred = std::equal_to<Key>,
           class Allocator = std::allocator<std::pair<const Key, T>>>
  class unordered_map;

  // Equality Comparisons
  template<class Key, class T, class Hash, class Pred, class Alloc>
    bool operator==(const unordered_map<Key, T, Hash, Pred, Alloc>& x,
                    const unordered_map<Key, T, Hash, Pred, Alloc>& y);

  template<class Key, class T, class Hash, class Pred, class Alloc>
    bool operator!=(const unordered_map<Key, T, Hash, Pred, Alloc>& x,
                    const unordered_map<Key, T, Hash, Pred, Alloc>& y);

  // swap
  template<class Key, class T, class Hash, class Pred, class Alloc>
    void swap(unordered_map<Key, T, Hash, Pred, Alloc>& x,
              unordered_map<Key, T, Hash, Pred, Alloc>& y)
      noexcept(noexcept(x.swap(y)));

  // Erasure
  template<class K, class T, class H, class P, class A, class Predicate>
    typename unordered_map<K, T, H, P, A>::size_type
      erase_if(unordered_map<K, T, H, P, A>& c, Predicate pred);

  template<class Key,
           class T,
           class Hash = boost::hash<Key>,
           class Pred = std::equal_to<Key>,
           class Allocator = std::allocator<std::pair<const Key, T>>>
  class unordered_multimap;

  // Equality Comparisons
  template<class Key, class T, class Hash, class Pred, class Alloc>
    bool operator==(const unordered_multimap<Key, T, Hash, Pred, Alloc>& x,
                    const unordered_multimap<Key, T, Hash, Pred, Alloc>& y);

  template<class Key, class T, class Hash, class Pred, class Alloc>
    bool operator!=(const unordered_multimap<Key, T, Hash, Pred, Alloc>& x,
                    const unordered_multimap<Key, T, Hash, Pred, Alloc>& y);

  // swap
  template<class Key, class T, class Hash, class Pred, class Alloc>
    void swap(unordered_multimap<Key, T, Hash, Pred, Alloc>& x,
              unordered_multimap<Key, T, Hash, Pred, Alloc>& y)
      noexcept(noexcept(x.swap(y)));

  // Erasure
  template<class K, class T, class H, class P, class A, class Predicate>
    typename unordered_multimap<K, T, H, P, A>::size_type
      erase_if(unordered_multimap<K, T, H, P, A>& c, Predicate pred);

  // Pmr aliases (C++17 and up)
  namespace pmr {
    template<class Key,
             class T,
             class Hash = boost::hash<Key>,
             class Pred = std::equal_to<Key>>
    using unordered_map =
      boost::unordered::unordered_map<Key, T, Hash, Pred,
        std::pmr::polymorphic_allocator<std::pair<const Key, T>>>;

    template<class Key,
             class T,
             class Hash = boost::hash<Key>,
             class Pred = std::equal_to<Key>>
    using unordered_multimap =
      boost::unordered::unordered_multimap<Key, T, Hash, Pred,
        std::pmr::polymorphic_allocator<std::pair<const Key, T>>>;
  } // namespace pmr

} // namespace unordered

using unordered::unordered_map;
using unordered::unordered_multimap;

} // namespace boost