(DE PRLENGTH (S)
,  (COND
,  ,  ((ATOM S) (ATOMLENGTH S))
,  ,  ( T
,  ,  ,  (PLUS 1 (LENGTH S)
,  ,  ,  ,  (APPLY 'PLUS (MAPCAR S 'PRLENGTH))
,  ,  ,  ,,,)
,  ,  ,,,)
,  ,,,)
,,,)