[no subject]

[MLB@MIT-AI]

I don't understand why UNDEFUN does this interchanging business.  It seems
the right thing would be for DEFUN and company to push any existing definition
onto a list kept on the :PREVIOUS-DEFINITION property and for UNDEFUN etc to
pop it off.  I actually have use for this sort of "function-cell lambda-binding"
type behavior in some hairy macros I am writing.