- relocate the pair_entry (HashTable) and unary_entry (HashSet) into
the Detail namespace and add output handling.
The output handling at this level removes the reliance on zero::null
output (HashSet) and allows direct support of pointers.
This means that the following now works
HashTable<T*> tbl;
os << tbl;
It also means that we don't need to overload operator<< for
HashPtrTable anymore.
- avoid delete/new when calling HashSet::set(). If the entry already
exists there is no reason to remove it and add another one with the
same content.
STYLE: HashTable iterators now have a val() method
- identical to the object() iterator method, but shorter to type.