I'm exploring another corner of the Interlisp ecosystem and history: the Interlisp-10 implementation for DEC PDP-10 mainframes, a 1970s character based environment that predated the graphical Interlisp-D system. I approached this corner when I set out to learn and experiment with a tool I initially checked out only superficially, the TTY editor. This command line structure editor for Lisp code and expressions was the only one of Interlisp-10. The oldest of the Interlisp editors, it came befor...