Anyway, just after I sent the question a thing crossed my mind it happened to
be a (or the) solution to the problem: the modified grammar has to be applied
to $*LANG alongside with the MAIN slang. But then again, this is what I learned
from add_package_declarator with only vague idea of why it
This feels like you’re getting into the bleeding edges of MOP. My
understanding is that a MVMContext is purely a runtime thing. Not sure how it
comes to be that the MVMContext needs serializing, but that error message
indicates that the VM is not ready to do that.
So my guess is that somehow
