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How to define a trait with methods accepting any subtype of a particular trait

Try this

trait AppModel {}
trait ModelOperations {
  def get[T<:AppModel](model: T): Option[T]
  def create[T<:AppModel](model: T): Boolean

class User extends AppModel { val id = "xyz" val name = "abc" }

class UserOperations extends ModelOperations { override def get[User](user: User) : Option[User] = { // get a new user object by filtering existing parameters return None } override def create[User](user: User): Boolean = { // do something return false } }

Categories : Scala

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