Omer Katz

That's true for most languages. Python uses an exception to stop a generator from iterating. See https://docs.python.org/2/library/exceptions.html#exceptions.StopIteration Django uses ValidationError regularly in order to report validation failures. It's more pythonic.

Doesn't V8 have it's own GIL? What would happen if you initialize multiple VMs inside a process?

Oh that's really cool. I didn't know that it was possible. If you try to do the same with Python you're going to encounter some nasty issues.

I thought that it's not possible since in MRI Ruby you are not allowed to use more than one V8 VM in one process.

Actually ExecJS disallows it and both therubyracer and miniracer don't support it. Kudos on having that already built in.

It is likely that this PR would be accepted if it had tests.

I'd be very interested to check what needs to be done for Celery to work with Graal. I hope you'll run the test suite for it soon.

I maintain Celery and I'd like to allow support for other interpreters as well.

Before merging this I need to add tests.

So it turns out this library indeed doesn't support partial doubles. We can fix the tests because now we get a proper error. I'd appreciate a code review before going...