The interpreter stuff's simple enough--we teach the ops preprocessor
to handle them the same way that it does string constants, and index
into the PMC constant table. We'll want to put them in a separate
part of the bytecode file, so we probably ought to nail down metadata
so we can fully expose bytecode files to running code. And we need to
finish that fight over freeze/thaw methodologies, as constant PMCs
would end up being frozen in the bytecode.

As for the actual declaration of the constants... That's going to be
somewhat interesting. I can see one of two ways of doing it:

1) we execute the initialization code at compiletime and freeze the result
2) We compile the initialization code and execute it at runtime to
create the PMC

Both have their drawbacks when it comes to more complex PMCs. For
simple stuff it's not a big deal one way or the other, and for the
base PMC types we can even cheat and teach imcc how to create the
freeze format directly, but that's not tenable as a full solution.
--
                                         Dan

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Dan Sugalski                          even samurai
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