anchor.diff:  					       (loop
   						  with env = env
   						  for (name . lambda) in (binds flet)
  -						  do (setf env (register env :flet name lambda))
  +						  do (extend env :flet name lambda)
   						  finally (return env))
   					       :declare t)))))
   
  
positive.code:                                  (second form)))
      (dolist* ((var . value) (binds let))
        (declare (ignore value))
        (setf env (register env :let var :dummy)))
      (multiple-value-setf ((body let) nil (declares let)) (walk-implict-progn let (cddr form) env :declare t))))
  
  (defclass let*-form (variable-binding-form)
  
negative.code:   (with-form-object (symbol-macrolet symbol-macrolet-form :parent parent :source form
                                       :binds '())
      (dolist* ((symbol expansion) (second form))
        (extend env :symbol-macrolet symbol expansion)
        (push (cons symbol expansion) (binds symbol-macrolet)))
      (setf (binds symbol-macrolet) (nreverse (binds symbol-macrolet))
            (body symbol-macrolet) (walk-implict-progn parent (cddr form) env))))
  