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iOS Object-Oriented Swift 2.0 Classes Helper Methods

Lana Wong
Lana Wong
3,968 Points

I do not understand

I like to copy all these works down, so I could reference them in the future. For some reason, my code does not work.

class Tower{
    let position: Point
    var range: Int = 1
    var strength: Int = 1

    init(x: Int, y: Int){
        self.position = Point(x: x, y: y)

func fireAtEnemy(enemy: Enemy) {
        if inRange(self.position, range: self.range, target: enemy.position) {
            while enemy.life > 0 {
                print("Enemy vanquished!")

        }else {
            print("Darn! Enemy out of range!")

    func inRange(position: Point, range: Int, target: Point) -> Bool {
        let availablePositions = position.surroundingPoints(withRange: range)
        for point in availablePositions {
            if (point.x == target.x) && (point.y == target.y) {
                return true
        return false

If you test this on Xcode, you will see the problem.


1 Answer

The two methods should be inside the Tower class. Copy and paste fireAtEnemy() and inRange() inside the Tower class.