How do I setup multiple ORed type bounds in Scala

Question

Is it possible to do something like this in Scala: ``` class MyTest { def foo[A <: String _or_ A <: Int](p:List[A]) = {} } ``` That is, the type `A` could be a `String` or `Int`. Is this possible? (Similar question here)

Accepted Answer

Not really possible as you put it, but you can do it using the type class pattern. For example, from here:

```
sealed abstract class Acceptable[T]
object Acceptable {
  implicit object IntOk extends Acceptable[Int]
  implicit object LongOk extends Acceptable[Long]
}

def f[T: Acceptable](t: T) = t

scala> f(1)
res0: Int = 1

scala> f(1L)
res1: Long = 1

scala> f(1.0)
<console>:8: error: could not find implicit value for parameter ev: Acceptable[Double]
f(1.0)
^
```

EDIT

This works if class and object are companions. On REPL, if you type each on a different line (ie, a "result" appears between them), they are not companions. You can type it like below, though:

```
scala> sealed abstract class Acceptable[T]; object Acceptable {
     |   implicit object IntOk extends Acceptable[Int]
     |   implicit object LongOk extends Acceptable[Long]
     | }
defined class Acceptable
defined module Acceptable
```

How do I setup multiple ORed type bounds in Scala

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