Re: Function CCL::STRUCTURE-SLOT-NAMES undefined.

[york@oakland-hills.lucid.com (Bill York)]

In article <9210231605.AA28934@cambridge.apple.com> bill@cambridge.apple.com (Bill St. Clair) writes:

   >Date: Fri, 23 Oct 92 05:07:35 PDT
   >From: rem@public.btr.com (Robert E. Maas  rem@btr.com)
   >There should be some way that system packages can be write-protected,
   >so that if you try to INTERN anything into them that is not already
   >there an error is signalled. Is that mechanism available in any version
   >of MCL or is it proposed in future versions?

   I have never heard this idea before. It sounds reasonable.
   Maybe it could be controlled by *warn-if-redefine-kernel* and signal
   a continuable error, just as DEFUN does when one attempts to redefine
   a kernel function. One drawback is that lots of the example files
   intern symbols in the CCL package. Opinions?

I think that locked COMMON-LISP and CCL packages are probably the
right way to go.  As you said, the behavior could be controlled by a
flag.  As for random software that defines stuff in the CCL package,
you could do what we did with CLIM and provide a pre-defined CCL-USER
(and maybe even CCL-DEMO) package that those things are free to
modify.