anchor.diff:  
   (defun symbol-function (symbol)
     (declare (type symbol symbol))
  -  (sicl-env:fdefinition symbol sicl-env:*global-environment*))
  +  (sicl-genv:fdefinition symbol sicl-genv:*global-environment*))
   
   ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
   ;;;
  
positive.code: (defun (setf symbol-function) (new-definition symbol)
    (declare (type function new-definition)
  	   (type symbol symbol))
    (setf (sicl-env:fdefinition symbol sicl-env:*global-environment*)
  	new-definition))
  
  ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
  
negative.code:   (declare (type symbol symbol)
  	   (type function new-function))
    (when (null environment)
      (setf environment sicl-genv:*global-environment*))
    (setf (sicl-genv:macro-function symbol environment)
  	new-function))
  
  ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
  