importJava "org.simantics.scl.runtime.procedure.Ref" where
    data Ref a
    
    @JavaName "<init>"
    ref :: a -> <Proc> (Ref a)
    
    @JavaName "value"
    getRef :: Ref a -> <Proc> a
    
    @JavaName "<set>value"
    (:=) :: Ref a -> a -> <Proc> ()

main = do
    r = ref (13 :: Integer)
    r := (14 :: Integer)
    getRef r
--
14