It is strictly less powerful than a REPL. Claiming that you can't live code a game at a REPL is false, because I do it on a regular basis. When I write games

It is strictly less powerful than a REPL. Claiming that you can't live code a game at a REPL is false, because I do it on a regular basis. When I write games in Scheme, I use a REPL to write the game live, doing all of my editing within Emacs. I do not have to save files for the code to be evaluated, I just press a keystroke to evaluate the specific form I'm interested in. I can evaluate more fine-grained sections of code, not only entire files.