This is memo. Other typed_column<T>::remove does swap and pop_back, but for bit vector it just does erase. This is a bug. Note that column_table depends on the former behavior at https://github.com/gintenlabo/jubatus/blob/a481e2993e9962f8803d5f16ff2cf14cbd8976e8/jubatus/core/table/column/column_table.hpp#L404. This behavior is not introduced by this refactoring; it is common to those at develop branch: https://github.com/jubatus/jubatus/blob/develop/jubatus/core/table/column/columns.hpp#L141, https://github.com/jubatus/jubatus/blob/develop/jubatus/core/table/column/columns.hpp#L269.

Fortunately (and unfortunately), this function is not used from anywhere, yet :(