scala - Sum or Product Type? -

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given following algebraic data type:

scala> sealed trait person defined trait person  scala> case class boy(name: string, age: int, x: string) extends person defined class boy  scala> case class girl(name: string, age: int, y: boolean) extends person defined class girl

note - know it's not recursive type - there's no recursion involved.

so, sum or product type? why?


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