anchor.diff:          (xchg start end))
         (copy (nthcdr start seq) (- end start)))))
   
  -(defun subseq-sequence (maker seq start end)
  +(defun %subseq-sequence (maker seq start end)
     (when (> start end)
       (xchg start end))
     (with (seqlen  (length seq))
  
positive.code:         (dotimes (x l s)
  	  	  (setf (elt s x) (elt seq (+ start x))))))))
  
  (defun subseq (seq start &optional (end 99999))
    (when seq
  	(if
  	  (consp seq)
  		(subseq-list seq start end)
  	  (stringp seq)
  		(subseq-sequence #'make-string seq start end)
  	  (arrayp seq)
  		(subseq-sequence #'make-array seq start end)
  	  (error "type not supported"))))
  
  (define-test "SUBSEQ basically works"
    ((subseq '(1 2 3 4) 1 3))
  
negative.code: ;;;;; TRE environment
  ;;;;; Copyright (c) 2007-2009 Sven Klose <pixel@copei.de>
  ;;;;;
  ;;;;; Subsequences
  
  