scratch.sc

final case class Person(name: String, age: Int, email: String)

final case class PersonBuilder[Name[_], Age[_], Email[_]] private (
    private val name: Name[String],
    private val age: Age[Int],
    private val email: Email[String]
)

object PersonBuilder {
  type Initial[A] = Option[A]
  type Id[A] = A

  def apply(): PersonBuilder[Initial, Initial, Initial] = PersonBuilder(None, None, None)

  implicit final class NameOps[Age[_], Email[_]](private val builder: PersonBuilder[Initial, Age, Email]) {
    def name(value: String) = builder.copy[Id, Age, Email](name = value)
  }

  implicit final class AgeSyntax[Name[_], Email[_]](private val builder: PersonBuilder[Name, Initial, Email]) {
    def age(value: Int) = builder.copy[Name, Id, Email](age = value)
  }

  implicit final class EmailSyntax[Name[_], Age[_]](private val builder: PersonBuilder[Name, Age, Initial]) {
    def email(value: String) = builder.copy[Name, Age, Id](email = value)
  }

  implicit final class BuildSyntax(private val builder: PersonBuilder[Id, Id, Id]) {
    def build = Person(builder.name, builder.age, builder.email)
  }
}

// PersonBuilder().build() // does not compile (missing 3 params)
// PersonBuilder().name("diego").build() // does not compile (missing 2 params)
// PersonBuilder().name("diego").name("diego") // does not compile (called .name(..) more than once)
// PersonBuilder().name("diego").age(39).build // does not compile  (missing 1 param)
PersonBuilder().email("foo@bar").name("diego").age(39).build // val res0: Person = Person(diego,39,foo@bar)