
Hello there. Current implementation of hashed index has, at least, two issues, preventing me from re-using it in some places. First, the time for unlink operation in multi_index/detail/hash_index_node.hpp is O(m) where m is a occupancy of the given bucket. I'ts usually ok for unique index, but seems to hit performance of removing item in a non-unique index. It's all because of using single-linked list instead of double-linked one. Second, there is no possibility to use internal order of the records in the bucket, i.e. operations like popping the last element in the bucket's list. Such feature could be useful for, for example, priority queues. It could be realized by using such double-linked (or extra pointers in a bucket structure). Sure, I could get the current realization and write my own index, but it seems wiser to extend the current implementation to support custom bucket container or custom node as a template parameter. Thanks in advance. VV