Sounds like a potential keyword, or perhaps a ubiquitous method, or both. But how to differentiate "sealed under optimization" versus "sealed under inheritance"?
I don't understand the question.
The point is not for module authors to say "no one can ever extend or modify this class". It's for module users to say "I'm not extending or modifying this class".
Perhaps it would be better to specify an optimizability attribute at some level?
That seems possible, from the same level.
-- c
