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Tony Robinson
2,659 PointsObject-Oriented Swift 3: Overriding Properties - Why use "self" instead of "var"
The code below uses "self.life" to define the life variable in the Sub Class, but why can't we just use "var life = 50" instead? I guess I'm just not clear on when to use "self" vs using "var" within the Sub Classes.
class SuperEnemy: Enemy {
let isSuper: Bool = true
override init (x: Int, y: Int) {
super.init(x: x, y: y)
self.life = 50
}
}
2 Answers
james south
Front End Web Development Techdegree Graduate 33,271 Pointsin OOP, self (or this in some languages) refers to the instance or object, in this case a super enemy. the overridden init method sets the life value for each super enemy created to 50, which i assume is higher than regular enemies. var is used to declare variables and here i would assume it has been used in the enemy class to declare the life variable, and once declared there is no need to use the var keyword for that variable anymore. since we are inheriting from the enemy class, life does not need to be declared again and can be referred to in each object with the self keyword.
Tony Robinson
2,659 PointsThat makes complete sense! Since we've already created the "life" variable, we can reference it in our SubClasses using "self".
Thank you!