Skip to main content
RSS feed Subscribe to feed


Undoable Dictionaries

Undoable Dictionaries are analogous to Undoable Lists and Undoable Sets, but implement dictionaries.


The framework provides one class for undoable dictionaries:

Keys must be immutable and they cannot be document nodes.
Values must fulfill the same requirements – that is, immutable or document node – as any values in undoable nodes.

The dictionaries are implemented using a balanced binary search tree where the hash codes of the keys are used to order the elements. Thus adding, removing, looking up or checking for containment takes logarithmic time.

Implementation Pattern

Refer to Undoable Lists.