> worried about every what-if I hear you about this, but during prototyping one cannot be excessively concerned with did I change the global state enough such

> worried about every what-if I hear you about this, but during prototyping one cannot be excessively concerned with did I change the global state enough such that it's better to just start a new REPL (and have to worry about the associated costs)? And if you ask this question a lot, long running REPLs are not a good idea for development.