anchor.diff:     (sources         :type list))
     (:documentation
      "A kernel is the fundamental unit of work in Petalisp. It's BLUEPRINT
  -   describes how elements of the storage of TARGET can be computed by using
  -   elements of the storage of SOURCES. ITERATION-SPACE is a subspace of the
  -   index space of the storage of TARGET."))
  +    describes how elements of the storage of TARGET can be computed by
  +    using elements of the storage of SOURCES. ITERATION-SPACE is a subspace
  +    of the index space of the storage of TARGET."))
   
   (defmethod initialize-instance :after ; reference counting
       ((kernel kernel) &key &allow-other-keys)
  
positive.code: (defgeneric reference (object space transformation)
    (:documentation
     "Return a -- potentially optimized and simplified -- data structure
     equivalent to an instance of class REFERENCE.")
    (:method-combination or)
    (:method or ((object data-structure)
                 (space index-space)
  
negative.code:    (refcount     :type non-negative-fixnum :initform 0 :accessor refcount))
    (:documentation
     "A data structure of dimension D is a mapping from elements of
      INDEX-SPACE to values of type ELEMENT-TYPE.
  
      INPUTS is a list of data structures on which the definition of this data
      structure depends on.
  
      REFCOUNT is an implementation detail. For ordinary data structures it
      tracks how many times the data structure appears as an input of another
      data structure. For immediate data structures, it tracks how many times
      the data structure appears as the source of a kernel."))
  
  (defmethod initialize-instance :after ; reference counting
      ((instance data-structure) &key &allow-other-keys)
  