'override' keyword not required on subclass method

Elements Silver
1

The following compiles with only a warning on Silver: “Method hides a method in parent class”

class Plant {
    var height=0.0
    var age=0
    func getDetails()->String { return "Plant Details" }
}

class Tree:Plant {
    private var limbs=0
    func getDetails()->String { return "Tree Details" }
}

In Swift, compilation is supposed to fail and you are supposed to get error messages like the below:

main.swift:9:10: error: overriding declaration requires an 'override' keyword
    func getDetails()->String { return "Tree Details" }
         ^
    override 
main.swift:4:10: note: overridden declaration is here
    func getDetails()->String { return "Plant Details" }
         ^
2

This is “as designed”. Because in Cocoa all methods are overloaded if they have the same name, and there’s no mechanism in the underlying platform to prevent overloading, we emit this warning, instead of an error, when the override keyword is missing (as that’s how Objective-C would behave, as well). The proper fix is still to add “override”, to be on the clean side, of course.