template<typename Alloc>
struct bond::ext::detail::allocator_reference_type_workaround< Alloc, typename boost::enable_if_c< !std::is_void< typename Alloc::value_type >::value &&!(std::is_void< typename Alloc::reference >::value||std::is_void< typename Alloc::const_reference >::value)>::type >
Transfer reference
and const_reference
types if available.