Programs can manage more than one type of data and so can a function. We’ve previously only worked with one parameter per function, but Swift functions can accept multiple input values at a time separated by commas.

Take a function, for example, that determines if a race car driver can proceed to the next round of qualifications given their current performance. Since this depends on two different types of data, the driver’s speed and state of the car, we can set up multiple parameters in a function:

func didQualify(slowestDriver: Bool, retired: Bool) -> String {

  if slowestDriver || retired {
    return "Eliminated"
  } else {
    return "Qualified"
  }
}

Let’s peak under the hood:

• slowestDriver and retired are parameters of type Bool within the function, didQualify(slowestDriver:retired:) that returns a String value.
• The parameters are used in an if/else statement to determine whether or not the driver continues on to the next round.

Calling the function below, we pass in true for slowestDriver, and false for retired:

print(didQualify(slowestDriver: true, retired: false)) 

The if statement executes within the function with the Boolean values, and the functions returns "Eliminated".