[Ecls-list] Problem with descendants of STANDARD-CLASS

[Dan Corkill]

> The problem with ECL is that it got a "castrated" version of CLOS which
> aimed for simplicity and easy bootstrapping. I am now reimplementing the
> parts of the MOP which were missing. Lot has been done:
> finalize-inheritance, change-class, etc. But there might be still some
> bugs left and there are definitely things to do such as reimplementing
> methods in a more standard way.

In investigating a GBBopen port to ECL, I found that the latest CVS 
version of defclass does not allow additional class options associated 
with a metaclass (see #+cant-assume-this below, in this excerpt from 
defclass).  Some mechanism (such as an option-validation method) needs 
to be provided to allow class-option extensions.

>     (dolist (option args)
>       (let ((option-name (first option))
>             option-value)
>         (if (member option-name processed-options)
>             (si:simple-program-error
>              "Option ~s for DEFCLASS specified more than once"
>              option-name)
>             (push option-name processed-options))
>         (setq option-value
>           (case option-name
>             ((:metaclass :documentation)
>              (list 'quote (second option)))
>             (:default-initargs
>                 (setf option-name :direct-default-initargs)
>                 (parse-default-initargs (rest option)))
>             #+cant-assume-this
>             (otherwise
>              (si:simple-program-error "~S is not a valid DEFCLASS option"
>                                       option-name))))
>         (setf options (list* option-name option-value options))))

Also, I was surprised that only the following symbols were exported from 
the CLOS package:

clos:slot-definition-documentation
clos:slot-definition
clos:slot-definition-allocation
clos:slot-definition-name
clos:slot-definition-initfunction
clos:slot-definition-initargs
clos:slot-definition-initform
clos:slot-definition-readers
clos:slot-definition-type
clos:slot-definition-writers

I expected that all the AMOP symbols would be exported.

-- Dan