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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.