Given that a VirtualMachine could potentially take up a lot of memory, what would be the smartest way to make a JS class to manage it? The pyEval function is sufficient for simple things, but it might be desirable to persist the context over, e.g. for a REPL.

I see two or three ways to do this:

• Hold created VirtualMachines in a global HashMap by randomly generated IDs, and have a .destroy() method on the JS class that has to be called or risk a memory leak.
• Only allow one VirtualMachine per JS context, held in a global variable, initialized at load.
• Implement a way for the entire Python context to be serialized (probably not feasible at the moment, nor necessarily worth the time).

I considered some stuff with maybe JS WeakSets or WeakMaps (that take an object as a key but don't prevent it or its value from being garbage-collected), but I don't think that would be able to do anything.