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re: Random metaclasses for CL types
> Gabriel to Earth. Now hear this. My suggestion is to delete the
> following paragraph from the specification:
...
In other, words, delete the use of BUILT-IN-CLASS? I don't think that's a
good idea, because BUILT-IN-CLASS does serve a useful purpose: it serves
notice that there may exist some classes for which MAKE-INSTANCE and
SLOT-VALUE are not legal, and it provides a way to test whether a given
class has those restrictions. Thus, while the result of, for example,
(CLASS-OF (FIND-CLASS 'READTABLE))
should be permitted to be implementation-dependent, it should be
meaningful for portable code to test for
(TYPEP (FIND-CLASS 'READTABLE) 'BUILT-IN-CLASS)
in order to find out if READTABLEs can have slots in the current
implementation.