anchor.diff:  
   (defvar *configuration-schemas* (make-hash-table :test #'equal))
   
  +(defun find-configuration-schema (name)
  +  (multiple-value-bind (configuration-schema found-p)
  +      (gethash name *configuration-schemas*)
  +    (if found-p
  +	configuration-schema
  +	(error "Configuration schema ~A not defined" name))))
  +
   (defclass configuration-schema ()
     ((name :initarg :name
   	 :accessor name
  
positive.code:     (loop for section in (getf initargs :direct-sections)
  	  do
  	 (setf (gethash (name section) direct-sections) section))
      (setf (direct-sections configuration-schema) direct-sections)))
  
  (defclass configuration-schema-section ()
    ((name :initarg :name
  
negative.code: 	 :documentation "The configuration-schema name")
     (parents :initarg :parents
  	    :accessor parents
  	    :initform nil
  	    :documentation "Configuration-Schema mixins")
     (title :initarg :title
  	  :accessor title
  