anchor.diff:  		   #'((def vals)
   				(= no-static '&rest)
     			    (= rest-arg (list (. (argdef-get-name .def.)
  -                                     (. def. vals))))
  +                                     (. (make-symbol "%REST" "TRE")
  +                                        vals))))
   			    nil)
   
            exp-optional-rest
  
positive.code: 
  (defun argument-expand-values (fun def vals)
    (filter [? (& (cons? _)
                  (argument-rest-keyword? _.))
               ._
               _]
            (cdrlist (argument-expand fun def vals))))
  
negative.code: ; tré – Copyright (c) 2008–2015 Sven Michael Klose <pixel@hugbox.org>
  
  (defun argument-rest-keyword? (x)     (in? x (make-symbol "&REST" "TRE") (make-symbol "&BODY" "TRE")))
  (defun argument-keyword? (x)          (in? x (make-symbol "&REST" "TRE") (make-symbol "&BODY" "TRE") (make-symbol "&OPTIONAL" "TRE") (make-symbol "&KEY" "TRE")))
  