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FUNCTION and MACROLET



    To me, it isn't an obvious clarification that FUNCTION can return
strange objects.  I always though of function as causing "functional
evaluation", and would always result in a callable object.

    Are people really suggesting that the compiler should arrange to
compile and dump macrolet functions?  Is this legal?

(defun def-a-macro (name)
  (macrolet ((foo (a b) `(cons ,a ,b)))
     (setf (symbol-function name) #'foo)))

    Of course, if the manual is interpreted as saying that *nothing*
is guaranteed about what symbol-function returns in the non-function
case, then the compiler could compile the FUNCTION call so that it
returned something totally random.

    Unless more is guaranteed about what SYMBOL-FUNCTION does in the
non-function case, this option is useless.  I think it would better to
say that it is an error to call SYMBOL-FUNCTION on any symbol which
isn't the name of a function.  Sensibly, it is illegal to do anything
with a special-form object, and it is much more tasteful to manipulate macro
definitions using MACRO-FUNCTION, so it seems that the ability to call
SYMBOL-FUNCTION on non-functions it worthless.   And it we change
SYMBOL-FUNCTION in this way, then it would be consistent with what
FUNCTION already does in Spice Lisp.

  Rob