anchor.diff:  	  (print-program-usage/option-text '(("help" nil "This helpful message.")
   					     ("force" nil "Overwrite any existing output.")
   					     ("chains-verbose" nil "Output information about which leaf is being executed.")
  +                                             ("chains-succeed-on-error" nil "Return success if an error occurs.")
   					     ("chains-group-size" "size" "Execute <size> leaves starting at <leaf>*<size>.")))
   	  (print-program-usage/suffix)))
   
  
positive.code: 	    ,(when prologue
  	      `(progn
  		 ,@prologue))	    
  	    (if (perform-program ,tree ,depth ,leaf
                                   :force force
                                   :chains-group-size (or chains-group-size-value 1)
                                   :chains-verbose chains-verbose
                                   ,@(reduce #'append custom-options :key #'option-perform-arguments))
                  0
                  1)))))))
  
  
negative.code: 	(help-data (gensym "HELP-DATA")))
      `(let ((,help-data (list ,@(mapcar #'help-data custom-options))))
         (lisp-executable:define-program ,name
  	   (lisp-executable:&options help force chains-verbose chains-succeed-on-error (chains-group-size chains-group-size-value)
  				     ,@(mapcar #'option-definition custom-options)
  				     lisp-executable:&arguments ,tree ,depth ,leaf)
  	 (declare (lisp-executable:conversion-function (integer 1) ,depth)
  