anchor.diff:  ;; function
   (eval-when (:compile-toplevel :load-toplevel :execute)
     (when (find-symbol "*DEBUG-PRINT-VARIABLE-ALIST*" :sb-debug)
  -    (pushnew :hunchentoot-sbcl-debug-print-variable-alist *features*)))
  +    (pushnew :sbcl-debug-print-variable-alist *features*)))
   
   #+sbcl
   (defun print-backtrace-to-stream (stream)
  -  (let (#+:hunchentoot-sbcl-debug-print-variable-alist
  +  (let (#+:sbcl-debug-print-variable-alist
   	(sb-debug:*debug-print-variable-alist*
   	 (list* '(*print-level* . nil)
   		'(*print-length* . nil)
   		sb-debug:*debug-print-variable-alist*))
  -	#-:hunchentoot-sbcl-debug-print-variable-alist
  +	#-:sbcl-debug-print-variable-alist
   	(sb-debug:*debug-print-level* nil)
  -	#-:hunchentoot-sbcl-debug-print-variable-alist
  +	#-:sbcl-debug-print-variable-alist
   	(sb-debug:*debug-print-length* nil))
       (sb-debug:backtrace most-positive-fixnum stream)))
   
  
positive.code: 	(stream (values output nil)))
      (unwind-protect
  	 (progn
  	   (print-condition error stream)
  	   (format stream "~&Date/time: ~a" (date-time-string))
  	   (terpri stream)
  	   (print-backtrace-to-stream stream)
  	   (terpri stream)
  
negative.code: *current* error.
  ")
  
  (eval-when (:compile-toplevel :load-toplevel :evaluate)
    (unless (fboundp 'print-backtrace-to-stream)
      (defun print-backtrace-to-stream (stream)
        (format stream "~&backtrace output unavailable.~%"))))
  