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iOS Object-Oriented Swift 2.0 Classes Helper Methods

Posted by Lionel Coelho
Lionel Coelho
1,206 Points

Going a bit nuts here...

Whats wrong with my code? I keep getting this error:

Type '(Int) -> [Point]' does not conform to protocol 'Sequence'

on this line of code:

for point in availablePositions {

Here is my code:

struct Point {
    let x: Int
    let y: Int

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

    func surroundingPoints(withRange range: Int = 1) -> [Point] {
        var results: [Point] = []

        for xCoord in (x-range)...(x+range) {

            for yCoord in (y-range)...(y+range) {
                let coordinatePoint = Point (x: xCoord, y: yCoord)
                results.append(coordinatePoint)
            }
        }
        return results
    }
}

let coordinatePoint = Point(x: 2, y: 2)
coordinatePoint.surroundingPoints()

let coordinatePoint2 = Point(x: 3, y: 3)

class Enemy {
    var life: Int = 2
    let position: Point

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

    func decreaseHealth (factor: Int) {
        life = life - factor
    }
}

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(position: self.position, range: self.range, target: enemy.position) {
            while enemy.life > 0 {
                enemy.decreaseHealth(factor: self.strength)
                print("Enemy Vanquished!")

                }
            } else {
                print("Darn!! Missed")

            }
        }

        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

    }
}

let tower = Tower(x: 0, y: 0)
let enemy = Enemy(x: 1, y: 1)

tower.fireAtEnemy(enemy)

1 Answer

Michael Ayoub
Michael Ayoub
7,689 Points
Michael Ayoub
Michael Ayoub
7,689 Points

try replacing your code with this:

struct Point { let x: Int let y: Int

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

func surroundingPoints(withRange range: Int = 1) -> [Point] {
    var results: [Point] = []
    for xCoord in (x-range)...(x+range) {
        for yCoord in (y-range)...(y+range) {
            let coordinatePoint = Point(x: xCoord, y: yCoord)
            results.append(coordinatePoint)
        }
    }
    return results

}

}

let coordinatePoint = Point(x: 2, y: 2) coordinatePoint.surroundingPoints()

class Enemy { var life = 2 let position: Point

init(x: Int, y: Int) {
    self.position = Point(x: x, y: y)
}
func decreaseHealth(factor: Int) {
    life -= factor

}

}

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(initialPosition: self.position, range: self.range, target: enemy.position) {
        while enemy.life > 0 {
            enemy.decreaseHealth(factor: self.strength)
            print("Enemy vanquished!")
        }
    } else {
        print("Darn! The enemy is out of range!")
    }

}

func inRange(initialPosition: 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

}


}