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Type mismatch when using higher-kinded types


Type labmdas should help:

  class Bar[T[_]] {
    def bar[A]: Option[T[A]] = None
  }

  def foo[A] = {
    new Bar[({type M[B] = Map[A, B]})#M]
  }

  val f: Option[Map[String, Int]] =
foo[String].bar[Int]

However I can't answer why type T doesn't work in this case.


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