se-0244_model.swift

// MARK: - A generic device -

public protocol Device
{
    var name: String { get }
}

// MARK: - The iPhone -

public struct iPhone: Device
{
    private let model = "XR"

    public var name: String
    {
        return "iPhone"
    }
}

extension iPhone: Equatable
{
    public static func == (lhs: iPhone, rhs: iPhone) -> Bool
    {
        return (lhs.name == rhs.name) && (lhs.model == rhs.model)
    }
}

// MARK: - The Mac -

public struct Mac: Device
{
    private let model = 2015

    public var name: String
    {
        return "MacBook Air"
    }
}

extension Mac: Equatable
{
    public static func == (lhs: Mac, rhs: Mac) -> Bool
    {
        return (lhs.name == rhs.name) && (lhs.model == rhs.model)
    }
}

// MARK: - The Factory -

public struct AppleFactory
{
    /// A new Mac
    public static func makeMac() -> some Equatable
    {
        return Mac()
    }

    /// A new iPhone
    public static func makePhone() -> some Equatable
    {
        return iPhone()
    }
}