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Random metaclasses for CL types

re: . . . or any other implementation-defined
    class that is no more restrictive than a {\bit built-in class\/}.

I liked your first version better -- I don't remember  88-002R having
a well-ordered scale for "restrictiveness" of metaclasses, so this
phrase (for me) causes much more confusion than it clears up.  But
it's not a big point.

On a related theme -- I was wondering if everyone agrees that the
following is also permitted by "Integrating Types And Classes" section.
An implementation may have a subset of some built-in class being 
implemented by a different meta-class than the rest of the set.  For 
example, in most implementations we probably have:

   (class-name (class-of (find-class 'integer))) --> BUILT-IN-CLASS

But some implementation might also have a FIXNUM class such that:

   (class-name (class-of (find-class 'fixnum))) --> FAST-ARITH-CLASS

where FAST-ARITH-CLASS is not a subclass of BUILT-IN-CLASS.  Of course, 
the FIXNUM class is a still a subclass of INTEGER.

[don't take this example too seriously -- I'm more concerned about
subclasses of the FUNCTION class.]

Assuming that this is legit, then I guess the point you are trying to 
clear up is whether or not it is valid for the subset to be the
whole set -- i.e., some CL type is wholly implemented by a moderately
random metaclass.

-- JonL --