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andrew naeve
11,503 Pointsdot notation incorrect?
hey guys, sorry, having problems attaching my code for whatever reason. checking the box isnt working, so i've attached the last part of the problem where i suspect the problem lies. getting no usable errors. im guessing my "location.y-1" part is the wrong way to add or subtract from the coordinates in Point?
class Robot: Machine {
override func move(direction: String) {
switch direction {
case "Up" : location.y+1
case "Down": location.y-1
case "Left" : location.x-1
case "Right" : location.x+1
default: break
}
1 Answer
Steve Hunter
57,712 PointsHI Andrew,
You're on the right lines with this but you haven't altered the values of x or y.
You've started with the long-hand method, which is fine, You've taken the value at, say, location.x and then added one to that. But you never reassign that value back into location.x.
There's two ways to do this. Sticking with the long-hand method, change your code in this way:
case "Up" : location.y = location.y + 1
That will work for you. Alternatively, you can use the increment and decrement operators like this:
switch direction{
case "Up" : location.y++
case "Down" : location.y--
case "Left" : location.x--
case "Right" : location.x++
default : break
}
I hope that helps.
Steve.