I'm not a bad person. Why must the universe punish me so with Swift generics?

MoreBadKarmaFromGenerics.swift

struct ProtoOrder<T> {
    var quantity: T
    init(_ quantity: T) { self.quantity = quantity }
}

protocol ItemProtocol {
    associatedtype HowCounted: Numeric
    typealias Order = ProtoOrder<HowCounted>

    var order: Order { get set }

    mutating func deliver() -> Bool
}

extension ItemProtocol {
    mutating func deliver() -> Bool {
        return Utilities.deliver(order)
    }
}

struct Shovels: ItemProtocol {
    typealias HowCounted = Int
    var order: Order
}

struct Gravel: ItemProtocol {
    typealias HowCounted = Double
    var order: Order
}

enum Utilities {
    static func deliver<T>(_ order: ProtoOrder<T>) -> Bool where T == Int {
        return true
    }
}

Can you try something like this?

struct ProtoOrder<T> {
    var quantity: T
    init(_ quantity: T) { self.quantity = quantity }
}

protocol ItemProtocol {
    associatedtype HowCounted: Numeric
    typealias Order = ProtoOrder<HowCounted>

    var order: Order { get set }

    mutating func deliver() -> Bool
}

extension ItemProtocol {
    mutating func deliver() -> Bool {
        return Utilities<Int>.deliver(order)
    }
}

struct Shovels: ItemProtocol {
    typealias HowCounted = Int
    var order: Order
}

struct Gravel: ItemProtocol {
    typealias HowCounted = Double
    var order: Order
}

enum Utilities<T> {
    static func deliver<T>(_ order: ProtoOrder<T>) -> Bool {
        return true
    }
}

Or this

struct ProtoOrder<T> {
    var quantity: T
    init(_ quantity: T) { self.quantity = quantity }
}

protocol ItemProtocol {
    associatedtype HowCounted: Numeric
    typealias Order = ProtoOrder<HowCounted>

    var order: Order { get set }

    mutating func deliver() -> Bool
}

extension ItemProtocol {
    mutating func deliver() -> Bool {
        return Utilities.deliver(order)
    }
}

struct Shovels: ItemProtocol {
    typealias HowCounted = Int
    var order: Order
}

struct Gravel: ItemProtocol {
    typealias HowCounted = Double
    var order: Order
}

enum Utilities {
    static func deliver<T: Numeric>(_ order: ProtoOrder<T>) -> Bool {
        return true
    }
}