Keyword `void' cannot be used in this context

using UnityEngine;
using System.Collections;

public class NeedleRotateAround : MonoBehaviour {

public Transform gun;	
public Transform pivot;	

float prevAngle;


void Start () 
{
	prevAngle = gun.transform.rotation.eulerAngles.z;	
}

void Update () 
{
	float currentAngle = gun.transform.rotation.eulerAngles.z;	

	float deltaAngle = currentAngle - prevAngle;	
	
	if(deltaAngle != 0)
		transform.RotateAround(pivot.position, Vector3.forward, deltaAngle);
	
	prevAngle = currentAngle;
}

}

after typed those, console show me two errors.

  1. Keyword `void’ cannot be used in this context
  2. Unexpected symbol (', expecting )‘, ,', ;’, [', or =’

it said these happened on line 16. why is this happened?

I get no error what so ever. Try restarting the mono developer.