This assumes, that I keep backups of the original files by adding a '~'
to their name and if adding new files to create an empty file with the '~'
appended. This way I don't have to keep two source-trees.
I've done something similar for many years, but I use "-" as the added
character rather than "~". Emacs uses "~" for its backup files, and I wanted
the creation of an "official" edit to require manual intervention. I have a
simple script that renames "~" files to "-" if I'm sure I want to keep them.
Leonard