©ISO/IEC Dxxxx
template <class Key, class T, class Compare, class Allocator>
bool operator==(const map<Key, T, Compare, Allocator>& x,
const map<Key, T, Compare, Allocator>& y);
template <class Key, class T, class Compare, class Allocator>
bool operator< (const map<Key, T, Compare, Allocator>& x,
const map<Key, T, Compare, Allocator>& y);
template <class Key, class T, class Compare, class Allocator>
bool operator!=(const map<Key, T, Compare, Allocator>& x,
const map<Key, T, Compare, Allocator>& y);
template <class Key, class T, class Compare, class Allocator>
bool operator> (const map<Key, T, Compare, Allocator>& x,
const map<Key, T, Compare, Allocator>& y);
template <class Key, class T, class Compare, class Allocator>
bool operator>=(const map<Key, T, Compare, Allocator>& x,
const map<Key, T, Compare, Allocator>& y);
template <class Key, class T, class Compare, class Allocator>
bool operator<=(const map<Key, T, Compare, Allocator>& x,
const map<Key, T, Compare, Allocator>& y);
template <class Key, class T, class Compare, class Allocator>
void swap(map<Key, T, Compare, Allocator>& x,
map<Key, T, Compare, Allocator>& y)
noexcept(noexcept(x.swap(y)));
// 23.4.5, class template multimap:
template <class Key, class T, class Compare = default_order_t<Key>,
class Allocator = allocator<pair<const Key, T>>>
class multimap;
template <class Key, class T, class Compare, class Allocator>
bool operator==(const multimap<Key, T, Compare, Allocator>& x,
const multimap<Key, T, Compare, Allocator>& y);
template <class Key, class T, class Compare, class Allocator>
bool operator< (const multimap<Key, T, Compare, Allocator>& x,
const multimap<Key, T, Compare, Allocator>& y);
template <class Key, class T, class Compare, class Allocator>
bool operator!=(const multimap<Key, T, Compare, Allocator>& x,
const multimap<Key, T, Compare, Allocator>& y);
template <class Key, class T, class Compare, class Allocator>
bool operator> (const multimap<Key, T, Compare, Allocator>& x,
const multimap<Key, T, Compare, Allocator>& y);
template <class Key, class T, class Compare, class Allocator>
bool operator>=(const multimap<Key, T, Compare, Allocator>& x,
const multimap<Key, T, Compare, Allocator>& y);
template <class Key, class T, class Compare, class Allocator>
bool operator<=(const multimap<Key, T, Compare, Allocator>& x,
const multimap<Key, T, Compare, Allocator>& y);
template <class Key, class T, class Compare, class Allocator>
void swap(multimap<Key, T, Compare, Allocator>& x,
multimap<Key, T, Compare, Allocator>& y)
noexcept(noexcept(x.swap(y)));
namespace pmr {
template <class Key, class T, class Compare = default_order_t<Key>>
using map = std::map<Key, T, Compare,
polymorphic_allocator<pair<const Key, T>>>;
§ 23.4.2 906