[Boost-users] [multi-index] Key extractor for 1:n relationship?

All the key extractors in the documentation of Boost.MultiIndex return one value for an element in a container. Is it somehow possible to use a 1:n relationship between element and value? The documentation uses this container definition (among others): typedef multi_index_container< employee, indexed_by< hashed_unique< const_mem_fun >

employee_set;

Let's assume an employee can have more than one name (std::string becomes std::vectorstd::string). Now if someone searches for Tom or John the same employee should be returned by the container. Is this possible? Boris