Modelling objects

object.scm

(define (create-user name)
  (define say-hello
    (print "Hello " name))
  (define (change-name new-name)
    (set! name new-name)
    name)
  (define (dispatch method)
    (cond
      ((eq? method 'say-hello) say-hello)
      ((eq? method 'change-name) change-name)
      (else (raise "Invalid method"))))
  dispatch)

(define user (create-user "Keyvan"))

(user 'say-hello)
; Hello Keyvan

((user 'change-name) "John")

(user 'say-hello)
; Hello John

solo por ver como quedaba te lo he picado en scala xD

case class InmutableUser(name: String) ={
def sayHello:Unit = println s"hello $name"
def changeName(name: String): User = copy(name = name)
}

case class MutableUser(var name: String) ={
def sayHello:Unit = println s"hello $name"
def changeName(newName: String): Unit = name = newName
}