Re: fixing our problems with setf

[Danny Bobrow <Bobrow.pa@Xerox.COM>]

    Rules for the macroexpansion of (setf (foo x) y):

    (1) If the function-name foo refers to the global function
    definition, rather than a locally defined function or macro, and if
    there is a setf macro defined for foo, use the setf macro to
    compute the expansion.

    (2) If the function-name foo is defined as a macro in the
    current scope, use macroexpand-1 to expand (foo x) and try again.

    (3) If the function-name foo is defined as a special form in
    the current scope, signal an error.

    (4) Expand into the equivalent of
    (let ((#:temp-1 x)
	  (#:temp-2 y))
      (funcall #'(setf foo) #:temp-2 #:temp-1))

Do (1) and (4) together imply that if there is a macro definition for
foo, and there is an flet foo, but no (setf foo) defined, that the
expansion of
  (setf (foo ...)...)
uses (funcall #'(setf foo) ...) rather than the macro. This seems wrong
(inconsistent with CLtL ???).

    Normally one does not define both a setf function and a setf
    macro for the same reading function.
But if a (setf foo) is defined locally, it is always be used, whether or
not foo is defined locally or globally, right???

I think the rule might be stated that if there is no (setf foo) function
AND there is a setf macro, then the macro is used, else the (setf foo)
function is used in the expansion.  This is a slightly extended version
of your:
    In the absence of any setf macro definition, SETF of a function
    expands into a call to the setf function.  
But aside from these two glitches (or my misunderstanding), I agree.

danny