Check out example codes for "swift guard let". It will help you in understanding the concepts better.
Code Example 1
guard let value1 = number1, let value2 = number2 else { return }
Code Example 2
func submit() {
guard let name = nameField.text else {
show("No name to submit")
return
}
guard let address = addressField.text else {
show("No address to submit")
return
}
guard let phone = phoneField.text else {
show("No phone to submit")
return
}
sendToServer(name, address: address, phone: phone)
}
func sendToServer(name: String, address: String, phone: String) {
...
}
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