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Dynamic inheritance

I'm implementing a card game called set-back (my Nana's favorite game,
if you must know):

// ---- code ----
define class <suit> (<object>) end;
define class <hearts> (<suite>) end;
// ...
define class <face> (<object>) end;
define class <jack> (<face>) end;
// ...
// define class <card> (<suit>, <face>) end;  // ???
// the above definition legal, but I want _A_ card to
// be a subclass of a _specific_ suit and a _specific_
// face.
// -- end-code --

The question is:  how do I create a local <card> variable that is an
object of an unknown <face> and unknown <suit>, specifically so that
the dispatch mechanism resolves the cards properly.

<rules-detour>
(e.g. *trumps* may be set to <clubs>, and a trump card beats all other
(non-trump) cards.)  Jacks and 10s have special (scoring) properties,
as well as the high (usually the ace) and low card (usually the deuce)
of the trump.
</rules-detour>

So, I need to dispatch on the suit as well as on the face (as well as
on some special faces).

Does Dylan have a dynamic inheritance mechanism?  If not, what are some
common ways to handle this problem?  I've thought of having state slots
on <card> and dispatching on them by calling a fn with the slots as
parameters (State(305) indirection), but that's a bit more work than
DI.  Any other suggestions?

Sincerely,
Doug Auclair



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