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compiler-let and macrolet in macros



Consider the following hack.
  (defmacro with-car (&body body)
    `(compiler-let((operator 'car))
       ,. body))
  (defmacro with-cdr (&body body)
    `(compiler-let((operator 'cdr))
       ,. body)
  (defmacro right-side (exp) `(,operator ,exp))
What I want to know is will the following work
  (setf (with-car (right-side foo)) (with-cdr (right-side goo)))
Probably not.  Of course this can be transformed into
  (with-car (setf (right-side foo) (with-cdr (right-side goo))))
However, I think the latter is more obscure.  By the way, I don't believe
that an implementation of this sort using macrolet will work either.
	The point of all of this is that macroexpand does not expand either
compiler-let or macrolet.  Thus, setf can't see its real arguments.  There
is a solution to this kind of problem but it would require much more
sophisticated macro expansion than is done today or has been proposed.
Before, I endeavor to write up a proposal for better macro expansion
facilities, I want to know if anybody is interested in either the problem or
its solution.
	Jeff