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Re: Issue: LISP-SYMBOL-REDEFINITION (Version 5)



> On your ballot, Sun commented "This appears to disallow too much." 
> 
> What things would you allow that are disallowed by this proposal?

Well, that *is* a fair question.

At minimum, it seems excessive to disallow application of TRACE
to functions in the LISP package.  I have worked on implementations
of TRACE, and I believe it can work on functions in the Lisp package.
If we don't wish to support TRACE on all functions in the Lisp package,
we could require TRACE to either work or to not establish tracing
of the function.

I'd prefer to permit redefinition of macros and functions in the
LISP package, though I know there are difficulties.  One would have
to admit that the compiler may treat any or all of these as inline,
assuming the built-in definitions, regardless of any user's redefinition.
Implementations must also be permitted to call any function in the LISP
package from any code whatsoever in the implementation.  Perhaps this
makes redefinition unsupportable.