printConstraint.swift

@IBOutlet var easeInLabelLeadingConstraint: NSLayoutConstraint!
@IBAction func startAnimationButtonAction(_ sender: Any) {
    // Print out the corresponding information of easeInLabel before and after animation
    print("\(isAnimated ? "easeInLabel has been moved." : "easeInLabel is at its original position.")")
    print("easeInLabelLeadingConstraint: \(easeInLabelLeadingConstraint.constant)")
    print("easeInLabel frame: \(easeInLabel.frame)")
    print("*********************************************")
    // Animation function ...
}