Different types in Map Scala

Question

I need a Map where I put different types of values (Double, String, Int,...) in it, key can be String.

Is there a way to do this, so that I get the correct type with

Answer 1

If you want to do this you'd have to specify the type of Container to be Any, because Any is a supertype of both Double and String.

val d: Container[Any] = new Container(4.0)
val str: Container[Any] = new Container("string")
val m: Map[String, Container[Any]] = Map("double" -> d, "string" -> str)

Or to make things easier, you can change the definition of Container so that it's no longer type invariant:

class Container[+T](element: T) {
  def get: T = element
  override def toString = s"Container($element)"
}

val d: Container[Double] = new Container(4.0)
val str: Container[String] = new Container("string")
val m: Map[String, Container[Any]] = Map("double" -> d, "string" -> str)