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Start your free trialNiilo Pirttijärvi
Courses Plus Student 2,354 PointsEnums and objects challenge?
I don't understand what the underscore does in this code. Could someone explain it's purpose?
class Point {
var x: Int
var y: Int
init(x: Int, y: Int) {
self.x = x
self.y = y
}
}
enum Direction {
case left
case right
case up
case down
}
class Robot {
var location: Point
init() {
self.location = Point(x: 0, y: 0)
}
func move(_ direction: Direction) {
// Enter your code below
switch direction {
case .left:
location.x -= 1
case .right:
location.x += 1
case .down:
location.y -= 1
case .up:
location.y += 1
}
}
}
1 Answer
Gene Bogdanovich
14,618 PointsIn the "move" method, underscore allows you to omit parameter name "direction" when you call that method. If you were to call that method with underscore you'd write something like this: move(direction: .left) If you were to call that method without underscore you'd write something like this: move(.left)
It just reads better.