Trouble with java raycast scripts to open a door

I have been following a tutorial that i found on the internet on how to use Unity and right now i am learning raycasthit to open doors. well i followed the script that the guy wrote and it still won't work. this is the code that i am using

var rayCastLength = 5;

function update() { var hit : RaycastHit;

//Check if we're colliding
if(Physics.Raycast (transform.position, transform.forward, hit, rayCastLength))
{
    //... with the door
    if(hit.collider.gameObject.tag == "door")
    {
        //open the door!
        hit.collider.gameObject.animation.Play("door_open");
    }
}

}

any help here would be welcome