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Implementation of red-black trees in Common Lisp, including a persistent red-black tree that uses an append-only strategy for recording changes in a text file
Common Lisp
Branch: master

Merge pull request #1 from OdonataResearchLLC/master

Simplified lisp-unit Interface
latest commit f35a29f77c
@hargettp authored



This package is a Common Lisp implemention of red-black trees (
using the algorithms described in Introduction to Algorithms, by Thomas H. Cormen, Charles E. Leiserson, 
Ronald L. Rivest, and Clifford Stein.

In addition to a straight-forward in-memory implementation of red-black trees, an implementation of a persistent
tree is also included.  The persistent implementation uses a text file for storage (for human readability), and
uses an append-only strategy for updating that text file.  A footer always appears at the end of the file (actually, 
a footer and a backup copy of the footer), containing information about where the root of the tree is located
and other relevant housekeeping details.  A small header appears at the beginning of the file containing
a version number for the tree's storage format.  Under correct behavior, at no time is any byte of the file
written more than once.

Contact for any questions, comments, feedback, or contributions, and keep an eye on for info and news about hh-redblack.

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