It's like the prisoners of Plato's cave. One could describe it to you but it's nothing like trying it. I would suggest you look for some videos or blog explaini

It's like the prisoners of Plato's cave. One could describe it to you but it's nothing like trying it. I would suggest you look for some videos or blog explaining it, or take a a week-end to try. The term REPL is here deceptive. You can load the whole compiler and the whole program in memory in a server accepting code changes and interact with them iteratively and have transparent incremental compilation when editing the code.