Non-member lexicographical comparisons

template <typename T, typename Compare, typename Allocator>
bool operator<( const concurrent_multiset<T, Compare, Allocator>& lhs,
                const concurrent_multiset<T, Compare, Allocator>& rhs )

Returns: true if lhs is lexicographicaly less than rhs.

---

template <typename T, typename Compare, typename Allocator>
bool operator<=( const concurrent_multiset<T, Compare, Allocator>& lhs,
                 const concurrent_multiset<T, Compare, Allocator>& rhs )

Returns: true if lhs is lexicographicaly less or equal than rhs.

---

template <typename T, typename Compare, typename Allocator>
bool operator>( const concurrent_multiset<T, Compare, Allocator>& lhs,
                const concurrent_multiset<T, Compare, Allocator>& rhs )

Returns: true if lhs is lexicographicaly greater than rhs.

---

template <typename T, typename Compare, typename Allocator>
bool operator>=( const concurrent_multiset<T, Compare, Allocator>& lhs,
                 const concurrent_multiset<T, Compare, Allocator>& rhs )

Returns: true if lhs is lexicographicaly greater or equal than rhs.