OrdenamientoEstructuras

(define-struct email (remitente destinatario mensaje))

(define l (list
           (make-email "pedro" "maria" "hola xD")
           (make-email "carlos" "juan" "¿como anda?")
           (make-email "ana" "juana" "te odio :)")
                )
  )

(define (intro n lst)
  (cond
    [(empty? lst) (list n)]
    [else
     (cond
       [(string<? (email-remitente n) (email-remitente (first lst))) (cons n lst)]
       [else (cons (first lst) (intro n (rest lst)))]
       )
     ]
    )
  )

(define (ordenar lst)
  (cond
    [(empty? lst) empty]
    [else
     (intro (first lst) (ordenar (rest lst)))
     ]
    )
  )