anchor.diff:            (go ,starttag)
             ,endtag
             (return (progn ,@result)))))))
  -
  -(defmacro dolist-indexed ((iter index lst result &key (start-index 0))
  -			  &rest body)
  -  "Iterate over list."
  -  (let ((starttag (gensym))
  -        (endtag (gensym))
  -	(tmplst (gensym)))
  -    `(block nil
  -      (let ((,tmplst ,lst)
  -	    (,iter nil)
  -	    (,index ,start-index))
  -        (tagbody
  -          ,starttag
  -          (if (eq ,tmplst nil)
  -            (go ,endtag))
  -          (setq ,iter (car ,tmplst))
  -          ,@body
  -          (setq ,tmplst (cdr ,tmplst))
  -	  (setq ,index (+ 1 ,index))
  -          (go ,starttag)
  -          ,endtag
  -          (return ,result))))))
  
positive.code: ;;;; nix operating system project
  ;;;; list processor environment
  ;;;; Copyright (C) 2005-2007 Sven Klose <pixel@copei.de>
  ;;;;
  ;;;; List traversal
  
  
negative.code:         (go start)))))
  
  (defun map (func &rest lists)
    (%map func lists)
    nil)
  
  (defun mapcar (func &rest lists)
    "Calls function for all head CARs in lists. Then call with next elements.
  