Hash set with in-place open-addressing, storing keys (elements) of type K.
Is true iff T has a specific value dedicated to representing holes (removed/erase) values.
Remove all elements in x matching pred.
Range over elements of l-value instance of this.
Hash table/map with open-addressing and hybrid storage, storing keys of type K and values of type V. Setting V to void turns the map into a set.
Default key equality/equivalence predicate for the type T.