[ED.BF---AN OPINIONATED ED RE-IMPLEMENTATION IN BRAINFUCK The original grep [as part of ed text editor] was written [overnight] in PDP-11 assembly language [by Ken Thompson]. -- Brian Kernigan, in the YouTube Computerphile video about grep (https://www.youtube.com/watch?v=NTfOnGZUZDk). Not being Ken Thompson is a struggle every working software engineer has to contend with. -- David Gillies, a You