//MARK: Create Specifications
protocol Specification {
    associatedtype T

    func isSatisfied(item: T) -> Bool
}

struct ColorSpecification: Specification {
    typealias T = Product

    var color: Color

    func isSatisfied(item: Product) -> Bool {
        return item.color == color
    }
}

struct SizeSpecification: Specification {
    typealias T = Product

    var size: Size

    func isSatisfied(item: Product) -> Bool {
        return item.size == size
    }
}