anchor.diff:             "EQUIVALENCE-CLASSES" "SUBSETS" "COMBINE" "IOTA"
              "MAKE-LIST-OF-RANDOM-NUMBERS" "LIST-INSERT-SEPARATOR"
              "NSPLIT-LIST-ON-INDICATOR" "NSPLIT-LIST" "DEEPEST-REC" "DEEPEST" "DEPTH"
  -           "FLATTEN" "LIST-TRIM" "TRANSPOSE" "AGET" "MEMQ" "PLIST-REMOVE" "PLIST-GET"
  +           "FLATTEN" "LIST-TRIM" "TRANSPOSE" "AGET" "MEMQ"
  +           "PLIST-KEYS" "PLIST-REMOVE" "PLIST-GET"
              "PLIST-PUT" "HASHED-INTERSECTION"
              ;; "HASHED-REMOVE-DUPLICATES" moved to COM.INFORMATIMAGO.COMMON-LISP.CESARUM.SEQUENCE
              "ENSURE-LIST" "PROPER-LIST-P" "LIST-LENGTHS"
  
positive.code: ;;;;LEGAL
  ;;;;    GPL
  ;;;;
  ;;;;    Copyright Pascal J. Bourguignon 2002 - 2011
  ;;;;
  ;;;;    This script is free software; you can redistribute it and/or
  ;;;;    modify it under the terms of the GNU  General Public
  
negative.code:       :finally (return (values i i 0)))))
  
  
  (defun plist-keys (plist)
    "Returns a list of the properties in PLIST."
    (loop :for (key) :on plist :by (function cddr) :collect key))
  
  
  (defun plist-put (plist prop value)
    "
  