RE: The Revenge of Finalizers

I'd hoped that blockFinalizers would be useful for defining other primitives but since it won't even work for GHC, I agree that PVar will meet most of our needs. (An even simpler design might be to extend our IORef implementations with 'atomicallyModifyIORef'.)

So, is this a design that we could agree on?

I like it. I'd vote for 'atomicModifyIORef' rather than a new PVar type, though. Cheers, Simon