The Interlisp manual defines residential programming like this:
«The "residential" style, where you stay inside the environment throughout the development, is essential for these tools to operate.»
«The "residential" style, where you stay inside the environment throughout the development, is essential for these tools to operate.»
In Common Lisp, the compiled code and data are both saved as a memory snapshot, kind of like an OS image (think an ISO you can boot into). This means you can hot-swap the code part, while keeping the data and run-time configuration, on a running system.
A REPL is part of it, but it's not the whole picture.