An unordered data-structure with O(1) lookup, removal, iteration and O(1) amortized insertion.
Like a faster HashMap that chooses its own keys.
Also similar to a Vec<Option<T>>, where instead of calling Vec::remove elements are removed by setting the element to None.
See the documentation for more information.
This crate is partly a port of plf::colony, which is a
proposed addition
to the C++ standard library under the name std::hive.