2012-01-26: cows-0.2.tar.bz2 has wandered off again.
2011-11-22: cows had gone missing for many years but I recently found a copy of the source code on an old hard drive. I also found a partial Java implementation that I will make available once it is cleaned up (i.e., it compiles).
cows is a library of efficient "copy-on-write" data structures. Adding or removing an element from a cows collection creates a new collection and leaves the original one unmodified. The implementation uses advanced techniques to share as much data as possible between different versions of a collection.
cows is available for Python.
Downloads are available on the Files page.
This project is distributed under the GNU General Public License version 3.