Fatal Error... Please help

Just started on the iOS Apprentice (still on the first one, Bull’s Eye, page 65). I did everything that I was told to do, but I keep getting this message. Thread 1 exc_bad_instruction (code=exc_i386_invop subcode=0x0).

I get the error at the line; (slider.value) = Float(currentValue)

Can someone please explain what I did wrong and how I can solve the error?

Here is my code.

import UIKit

class ViewController: UIViewController {

var currentValue: Int = 50
var targetValue: Int = 0

@IBOutlet weak var slider: UISlider!

override func viewDidLoad() {

override func didReceiveMemoryWarning() {
    // Dispose of any resources that can be recreated.

func startNewRound() {
    targetValue = 1 + Int(arc4random_uniform(100))
    currentValue = 50
    (slider.value) = Float(currentValue)

@IBAction func showAlert() {
    let message = "The value of the slider is: \(currentValue)"
        + "\nThe target value is: \(targetValue)"
    let alert = UIAlertController(title: "Hello, World",
                                  message: message, preferredStyle: .Alert)
    let action = UIAlertAction(title: "OK", style: .Default, handler: nil)
    presentViewController(alert, animated: true, completion: nil)

@IBAction func sliderMoved(slider: UISlider) {
currentValue = lroundf(slider.value)



Odd. Try removing the parentheses from the left side, those are not needed.

Try cleaning your project and rebuilding.