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Sophia Chiang
736 Pointswhy is Robot method throwing an error
swift_lint.swift:45:1: error: expected declaration
^ swift_lint.swift:30:7: note: in declaration of 'Robot' class Robot: Machine { ^ swift_lint.swift:31:19: error: argument names for method 'move(direction:)' do not match those of overridden method 'move' override func move(direction: String) { ^ _ swift_lint.swift:40:51: warning: result of operator '+' is unused self.location.x - self.location.x + 1
class Point {
var x: Int
var y: Int
init(x: Int, y: Int) {
self.x = x
self.y = y
}
}
class Machine {
var location: Point
init() {
self.location = Point(x: 0, y: 0)
}
func move(_ direction: String) {
print("Do nothing Im a machine!")
}
}
class Robot: Machine {
override func move(direction: String) {
switch(direction) {
case "Up":
self.location.y = self.location.y + 1
case "Down":
self.location.y = self.location.y - 1
case "Left":
self.location.x = self.location.x - 1
case "Right":
self.location.x - self.location.x + 1
default:
break
}
}
1 Answer
Jeff McDivitt
23,970 PointsIt is because your override function does not match the initial method, you need _ direction. Also your switch statement could be simplified
class Point {
var x: Int
var y: Int
init(x: Int, y: Int) {
self.x = x
self.y = y
}
}
class Machine {
var location: Point
init() {
self.location = Point(x: 0, y: 0)
}
func move(_ direction: String) {
print("Do nothing Im a machine!")
}
}
class Robot: Machine {
override func move(_ direction: String) {
switch(direction) {
case "Up":
location.y += 1
case "Down":
self.location.y -= 1
case "Left":
self.location.x -= 1
case "Right":
self.location.x += 1
default:
break
}
}
}