I have been thinking about a new input paradigm, where people can use only their thumb to program. Hold the screen with thumb, a wheel comes up with a circle of

I have been thinking about a new input paradigm, where people can use only their thumb to program. Hold the screen with thumb, a wheel comes up with a circle of options, guessed based on (Markov chain?) a list of symbols most likely to be entered next. The language needs to work with that paradigm well and also it appears tricky to implement so I'm far from working on it...