How many of these have I done now? I don't even know.
- is a text editor. It's written in Tcl and uses the Tk GUI toolkit.
Yes, it uses a GUI, unlike every other text editor I've ever tried to write. Why? Because Tk is easy. I can write a text editor in 13 lines of code. Not a very good one, admittedly, but it does work.
At the moment, - doesn't do much. I've got a working editor, but not much else. It's got a fair way to go before it's usable for code editing.