Source-Comparison

This is Mark Kantrowitz's source-compare.lisp with a GUI added.  

Source-compare.lisp is essentially a UNIX diff command written in Lisp.  With the GUI you never have to type pathnames, and when a diff spec is printed, Alt-Double-Click pulls up the relevant code in Hemlock windows.

To give it a try:

cd ccl/contrib/
svn update
(require ;source-comparison)

That will add a Source-Compare...  entry to the Tools Menu.