anchor.diff:        :with strings = (mapcar
                          (lambda (item)
                            (etypecase item
  +                           (null                         "")
                              ((or string symbol character) (string item))
  -                           (null                         "")
                              (cons (if (every (function characterp) item)
                                        (coerce item 'string)
                                        (list (etypecase (first item)
  +                                             (null                         "")
                                                ((or string symbol character) (string (first item)))
  -                                             (null "")
  -                                             (cons (coerce (first item) 'string)))
  +                                             (cons                         (coerce (first item) 'string)))
                                              (second item)
                                              (third item))))))
                          list-of-string-designators)
  
positive.code:   (:use "COMMON-LISP"
          "COM.INFORMATIMAGO.COMMON-LISP.CESARUM.LIST"
          "COM.INFORMATIMAGO.COMMON-LISP.CESARUM.UTILITY"
          "COM.INFORMATIMAGO.COMMON-LISP.CESARUM.SEQUENCE")
    (:export
     "STRING-DESIGNATOR" "CHARACTER-DESIGNATOR"
     "NO-LOWER-CASE-P" "NO-UPPER-CASE-P" "MIXED-CASE-P"
  
negative.code: ;;;;AUTHORS
  ;;;;    <PJB> Pascal J. Bourguignon <pjb@informatimago.com>
  ;;;;MODIFICATIONS
  ;;;;    2016-01-16 <PJB> Added an ignorable declaration to prefixp and suffixp
  ;;;;                     to avoid a warning.
  ;;;;    2015-09-15 <PJB> prefixp and suffixp moved to sequence,
  ;;;;                     became generic functions; added methods for
  ;;;;                     string designators.
  