That lack of programmability is probably what ultimately will doom vi. It can't extend its domain.
Bill JoyYou can't prove anything about a program written in C or FØRTRAN. It's really just Peek and Poke with some syntactic sugar.
Bill JoyIf you stay up late and you have another hour of work to do, you can just stay up another hour later without running into a wall and having to stop. Whereas it might take three or four hours if you start over, you might finish if you just work that extra hour. If you're a morning person, the day always intrudes a fixed amount of time in the future. So it's much less efficient. Which is why I think computer people tend to be night people - because a machine doesn't get sleepy.
Bill Joy