We can now put to use what we learned about receiver and infix functions and create a DSL for validating objects. To keep it simple, we'll only be validatingInttypes.
First, we'll add the NumberValidator interface. This is where all the different validators can represent their validation logic:
interface NumberValidator
{
fun isValueValid(value: Int): Boolean
}Then, we need a type that will keep all the validators and the validated object. We'll name it Validator:
class Validator<T> private constructor(private val validatedObject: T) {
internal val validators = mutableListOf<NumberValidator>()
private lateinit var valueFactory: (T) -> Int
}To enforce type safety, the Validator type is generic. It has a list of validators and also holds a function type called valueFactory, which knows how to return a property that will be validated. Notice how the constructor is private. We don’t allow the validator type to be created from outside; instead, we use an...