Field Properties

Field.scala

package datadictionary
import datadictionary.Field.Modifier

type AnyField                                 = Field[?, Nothing, Nothing]
type AnyFieldHavingKeyOf[K <: Field.FieldKey] = Field[K, Nothing, Nothing]

final case class Field[Key <: Field.FieldKey, +A, +Attribs](key: Key) extends Serializable:
  def asConstant(using Attribs <:< Modifier.Assignable) = ???

  override def toString: String = key
  override def hashCode(): Int  = key.hashCode()

object Field:

  type FieldKey = String & Singleton

  def constant[K <: FieldKey](key: K): ConstantPartiallyApplied[K] = ConstantPartiallyApplied(key)
  def string[K <: FieldKey](key: K): Field[K, String, Modifier.Assignable] =
    Field[K, String, Modifier.Assignable](key)

  object Modifier:
    type Assignable
    type ReadOnly
    type Constant <: ReadOnly

  class ConstantPartiallyApplied[K <: FieldKey](key: K) extends AnyVal:
    def apply[A]: Field[K, A, Modifier.Constant] = as[A]
    def as[A]: Field[K, A, Modifier.Constant]    = Field[K, A, Modifier.Constant](key)