- Defined in namespace Smalltalk
- Superclass: Dictionary
- Category: Collections-Keyed
- I am a more efficient variant of Dictionary that cannot be used as a
pool dictionary of variables, as I don't use Associations to store
key-value pairs. I also cannot have nil as a key; if you need to be
able to store nil as a key, use Dictionary instead. I use the object
equality comparison message #= to determine equivalence of indices.