extension method type parameter bounded by class param

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Works as a regular class, not as a value class.

  import scala.util.control.Exception._

  implicit class RichCatch[T](val c: Catch[T]) extends AnyVal {
    def validation[U >: T](u: => U): Either[Throwable, U] = c.either(u) 
  }

[scabug]

Imported From: https://issues.scala-lang.org/browse/SI-7022?orig=1
Reporter: @retronym
Affected Versions: 2.10.0
See #6482

[scabug]

@paulp said:
This is #6482, fixed by ff9f60f420c0 in master. I believe it's an easy backport.

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@paulp said:
I just clicked assign-to-me but I won't get to it immediately or anything so take it back if you want it.

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@retronym said:
scala/scala#1976