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iOS Generics in Swift Generic Types Creating a Generic Type

Calvin Morley
PLUS
Calvin Morley
Courses Plus Student 4,957 Points

There seems to be a bug with this challenge. The code below works in my playgound yet its not being accepted.

Specifically saying compiler errors which I know there are not

struct Queue<Element> { var array: [Element]

var isEmpty: Bool {
    if array.isEmpty {
        return true
    } else {
        return false
    }
}

}

generics.swift
struct Queue<Element> {
    var array: [Element]

    var isEmpty: Bool {
        if array.isEmpty {
            return true
        } else {
            return false
        }
    }
}

1 Answer

Dhanish Gajjar
Dhanish Gajjar
20,185 Points

You haven’t set the array to be an empty array for initial value there. All it says is array is [Element]. It compiles because it then relies on you creating an instance of Queue and assigning an array to the property. Your computed property is correct. you just need to give the array an initial value of empty so it defaults to empty.

struct Queue<Element> {
    var array:[Element] = []

    var isEmpty: Bool {
        if array.isEmpty {
            return true
        } else {
            return false
        }
    }
}