anchor.diff:  (def-stream-location %track-location (stream-location x)
     (when track?
       (? (string? x)
  -       (adolist ((string-list x))
  +       (adosequence x
            (%track-location stream-location !))
          (when x
            (? (== 10 x)
  
positive.code: ; tré – Copyright (c) 2005–2006,2010,2012–2015 Sven Michael Klose <pixel@copei.de>
  
  (defvar *default-stream-tabsize* 8)
  
  
negative.code: 
  (defun stream-princ (x str)
    (?
      (cons? x)            (adolist (x x)
                             (stream-princ ! str))
      (| (string? x)
         (character? x))   (unless (& (string? x)
                                      (zero? (length x)))
  