Swift 5. To see IF A DATE HAS PASSED:
let expiryDate = "2020-01-10" // Jan 10 2020
let dateFormatter = DateFormatter()
dateFormatter.dateFormat = "yyyy-MM-dd"
if Date() < dateFormatter.date(from: expiryDate) ?? Date() {
print("Not Yet expiryDate")
} else {
print("expiryDate has passed")
}