An example of a boilerplate total distance function for a list of CLLocation objects.

BoilerplateDistance.swift

func totalDistance(of locations: [CLLocation]) -> CLLocationDistance {
    var distance: CLLocationDistance = 0.0
    var previousLocation: CLLocation?
    
    locations.forEach { location in
        if let previousLocation = previousLocation {
            distance += location.distance(from: previousLocation)
        }
        previousLocation = location
    }
    
    return distance
}