EDIT4 was a VERY early line editor for the PDP8 written by Alan Freeman at Edinburgh in the early 60's.
Author: Alan Freeman Family: LineEditorFamily EdinburghFamily EarlyEditorFamily Platform: DEC PDP-8 License: Commercial
I have no idea what happened to EDITs 1 through 3. A binary paper tape of this editor has been located and loaded up into the archives of the Edinburgh Computer History Project. This editor was the first that I know which allowed conditional execution of commands depending on the execution status of earlier commands. The mechanism used was fairly crude and was subsequently improved considerably in the ECCE editor by Hamish Dewar, but nevertheless EDIT4 was a seminal editor at Edinburgh.
Paper documentation is lodged with the Royal Scottish Museum, but we do have a crude photocopy of it and have scans of the photocopy online at the above project's web site.
EDIT5B was a derivative of both EDIT4 and ecce which was written as a thesis project by Chris Whitfield, and his thesis was recently found on paper tape and is online at http://history.dcs.ed.ac.uk/archive/apps/Whitfield-Thesis/thesis.html