struct Cat {
    static var allCats = [Cat]() // line 1: is this an array of struct Cat type?
    init() {
        Cat.allCats.append(self) //what is self? appending another struct Cat type to static allCats variable? i find it unusual to create arrays of struct types. Never seen before
    }
    static func chorus() {
        for _ in allCats {
            print("Meow!")
        }
    }
}

//my own code to test struct

let catTest = Cat() //create instance of Cat struct

Cat.init() //add another Cat struct type

Cat.chorus() //prints 2 times cos allCats has 2 elements appended from above 2 lines

//end

Hi, I am not sure if I understand the code. Is line 1 creating a static variable array with data type as struct? How would such an array with struct data type be used? Will this array have struct elements with each element having Cat struct properties and methods?