"Expression type 'Bool' is ambiguous without more context" in ternary operation - swift

Question

I am trying to pass an enum to a function that does an operation on that enum's arguments. I receive this error:
Expression type 'Bool' is ambiguous without more context
The same error happens in an equivalent if clause, so it's not the ternary operator itself that causes the problem.
enum auto {
case pkw (SerialNumber: String, Axles: Int, Weight: Float)
case lkw (SerialNumber: String, Axles: Int, Weight: Float)
}
func checkIntegrity(car: auto) -> Bool {
switch car {
case .pkw:
if (checkSerialNumber(serialNumber: .pkw.SerialNumber.rawValue)
&& checkWeight(weight: .pkw.Weight.rawValue)) { // Error here, "&&" is underlined
return true
} else {
return false
}
break;
case .lkw:
return (checkSerialNumber(serialNumber: .lkw.SerialNumber.rawValue)
&& checkWeight(weight: .lkw.Weight.rawValue)) ? true : false; // same error here, "&&" is underlined
break;
default:
return false
}
The other functions that are called just return a Bool:
func checkSerialNumber(serialNumber: String) -> Bool {
return serialNumber.contains("ABABWA") // changed after a hint in the comments
}
func checkWeight(weight: Float) -> Bool {
return (weight < 2)
}
I am suspecting something wrong with the enum and how I use them, but I haven't found the solution yet.

Answer 1

The error message is misleading. You want to check the associated values
of an enumeration value, therefore you must bind those in the case pattern:
func checkIntegrity(car: auto) -> Bool {
switch car {
case let .pkw(serialNumber, _, weight):
if checkSerialNumber(serialNumber: serialNumber)
&& checkWeight(weight: weight) {
return true
} else {
return false
}
break;
case let .lkw(serialNumber, _, weight):
return (checkSerialNumber(serialNumber: serialNumber)
&& checkWeight(weight: weight)) ? true : false;
break;
default:
return false
}
}
This can be simplified to
func checkIntegrity(car: auto) -> Bool {
switch car {
case let .pkw(serialNumber, _, weight),
let .lkw(serialNumber, _, weight):
return checkSerialNumber(serialNumber: serialNumber) && checkWeight(weight: weight)
}
}