CL-DIFFLIB is a Lisp library for computing differences between sequences. It is based on the Python difflib module.

CL-DIFFLIB is copyright John Wiseman and is covered by the MIT license.

See this lemonodor post for more information.

ASDF-install package (obsolete)

You may also be interested in Nathan Froyd's diff package (though it seems to support only SBCL).

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