primitive_obsession__user_with_value_objects.kt

class User(
    val name: Name,
    val age: Age
)

class Name private constructor(
    val value: String
) {
    companion object {
        fun of(value: String): Name {
            require(value.length in (2..25))
            return Name(value)
        }
    }
}

class Age private constructor(
    val value: Int
) {
    companion object {
        fun of(value: Int): Age {
            require(value in (0..110))
            return Age(value)
        }
    }
}