You can also sometimes combine the techniques in the article above to skip booleans entirely. Instead of passing in a `bool primeMember` that gets used in a cal

You can also sometimes combine the techniques in the article above to skip booleans entirely. Instead of passing in a `bool primeMember` that gets used in a calculation like deliveryTime = 3; if (primeMember) { deliveryTime = 1; } you can pass in a `Membership memberType` value that contains the required information, so the above conditional turns into just the assignment deliveryTime = memberType.deliveryTime; This is more amenable to extension and contraction: you can add or remove different classes of delivery times without changing the logic in which it's used. You can even use private constructors and public static fields to create a list of "constants" containing the known member types, like the `Membership.REGULAR` and `Membership.PRIME`, retaining the property of the code not being able to use an invalid membership type. This can be used also for more complicated conditionals like the one in the article, by having a factory method that copies the right "constant" composite value based on whatever logic is desired.