template<class T>
associated_allocator_t<T> get_associated_allocator(const T& t) noexcept;
Returns: associated_allocator<T>::get(t).
template<class T, class ProtoAllocator>
associated_allocator_t<T, ProtoAllocator>
get_associated_allocator(const T& t, const ProtoAllocator& a) noexcept;
Returns: associated_allocator<T, ProtoAllocator>::get(t, a).