Thanks for taking the time to respond. I wrote up my comment just to point out some of the weaknesses I have identified in REPL-based development, and how to wa

Thanks for taking the time to respond. I wrote up my comment just to point out some of the weaknesses I have identified in REPL-based development, and how to watch out for those pitfalls as a program scales. For what it's worth, I agree with your sentiment, and believe REPL-based development should always be an option. I have a lot of success using REPL-based "prototyping", even in python, where I will quickly try/test something at a REPL before scaling it up, and having that utility to try/test/experiment quickly is often invaluable (especially if the standard build time is on the scale of minutes).