import collection.mutable

object Test {
  class IMap0[K[_], V[_]](backing: Map[K[_], V[_]]) {
    def mapSeparate[VL[_], VR[_]](f: V[_] => ({type l[T] = Either[VL[T], VR[T]]})#l[_] ) = {
      backing.view.map { case (k,v) => f(v) match {
	case Left(l) => Left((k, l))
	case Right(r) => Right((k, r))
        }
      }
    }
  }
}

exception when traversing ((x0$1: (K[_], V[_])) => x0$1 match {
  case (_1: K[_], _2: V[_])(K[_], V[_])((k @ _), (v @ _)) => f.apply(v) match {
    case (a: VL[_$4])Left[VL[_$4],VR[_$4]]((l @ _)) => new Left[(K[_0], VL[_$4]),Nothing](new (K[_0], VL[_$4])(k, l))
    case (b: VR[_$4])Right[VL[_$4],VR[_$4]]((r @ _)) => new Right[Nothing,(K[_0], VR[_$4])](new (K[_0], VR[_$4])(k, r))
  }
})
exception when traversing IMap0.this.backing.view.map[Product1[(K[_ >: _0 with _0], Any)] with Serializable with Either[(K[_0], VL[_$4]),(K[_0], VR[_$4])] forSome { type _0; type _0; type _$4 }, scala.collection.IterableView[Product1[(K[_ >: _0 with _0], Any)] with Serializable with Either[(K[_0], VL[_$4]),(K[_0], VR[_$4])] forSome { type _0; type _0; type _$4 },Iterable[_]]](((x0$1: (K[_], V[_])) => x0$1 match {
  case (_1: K[_], _2: V[_])(K[_], V[_])((k @ _), (v @ _)) => f.apply(v) match {
    case (a: VL[_$4])Left[VL[_$4],VR[_$4]]((l @ _)) => new Left[(K[_0], VL[_$4]),Nothing](new (K[_0], VL[_$4])(k, l))
    case (b: VR[_$4])Right[VL[_$4],VR[_$4]]((r @ _)) => new Right[Nothing,(K[_0], VR[_$4])](new (K[_0], VR[_$4])(k, r))
  }
}))
exception when traversing IMap0.this.backing.view.map[Product1[(K[_ >: _0 with _0], Any)] with Serializable with Either[(K[_0], VL[_$4]),(K[_0], VR[_$4])] forSome { type _0; type _0; type _$4 }, scala.collection.IterableView[Product1[(K[_ >: _0 with _0], Any)] with Serializable with Either[(K[_0], VL[_$4]),(K[_0], VR[_$4])] forSome { type _0; type _0; type _$4 },Iterable[_]]](((x0$1: (K[_], V[_])) => x0$1 match {
  case (_1: K[_], _2: V[_])(K[_], V[_])((k @ _), (v @ _)) => f.apply(v) match {
    case (a: VL[_$4])Left[VL[_$4],VR[_$4]]((l @ _)) => new Left[(K[_0], VL[_$4]),Nothing](new (K[_0], VL[_$4])(k, l))
    case (b: VR[_$4])Right[VL[_$4],VR[_$4]]((r @ _)) => new Right[Nothing,(K[_0], VR[_$4])](new (K[_0], VR[_$4])(k, r))
  }
....
....
blablabla
....
....
error: scala.reflect.internal.Types$TypeError: type mismatch;
 found   : Product1[(K[_ >: _0(in value $anonfun) with (some other)_0(in value $anonfun)], Any)] with Serializable with Either[(K[_0(in value $anonfun)], VL[_$4(in value $anonfun)]),(K[(some other)_0(in value $anonfun)], VR[_$4(in value $anonfun)])] where type _$4(in value $anonfun), type (some other)_0(in value $anonfun), type _0(in value $anonfun)
 required: Product1[(K[_ >: _0(in value $anonfun) with (some other)_0(in value $anonfun)], Any)] with Serializable with Either[(K[_0(in value $anonfun)], VL[(some other)_$4(in value $anonfun)]),(K[(some other)_0(in value $anonfun)], VR[(some other)_$4(in value $anonfun)])] forSome { type _0(in value $anonfun); type (some other)_0(in value $anonfun); type (some other)_$4(in value $anonfun) }
	at scala.tools.nsc.typechecker.Contexts$Context.error(Contexts.scala:283)
	at scala.tools.nsc.typechecker.Infer$Inferencer.error(Infer.scala:207)
	at scala.tools.nsc.typechecker.Infer$Inferencer.typeError(Infer.scala:217)
	at scala.tools.nsc.typechecker.Infer$Inferencer.typeErrorTree(Infer.scala:255)
	at scala.tools.nsc.typechecker.Typers$Typer.adapt(Typers.scala:980)
	at scala.tools.nsc.typechecker.Typers$Typer.typed(Typers.scala:4360)
	at scala.tools.nsc.typechecker.Typers$Typer.transformedOrTyped(Typers.scala:4507)
	at scala.tools.nsc.typechecker.Typers$Typer.typedDefDef(Typers.scala:1813)
	at scala.tools.nsc.typechecker.Typers$Typer.typed1(Typers.scala:4011)
	at scala.tools.nsc.typechecker.Typers$Typer.typed(Typers.scala:4351)
	at scala.tools.nsc.typechecker.Typers$Typer.typedStat$1(Typers.scala:2169)
	at scala.tools.nsc.typechecker.Typers$Typer$$anonfun$23.apply(Typers.scala:2257)
	at scala.tools.nsc.typechecker.Typers$Typer$$anonfun$23.apply(Typers.scala:2257)
	at scala.collection.immutable.List.loop$1(List.scala:150)
	at scala.collection.immutable.List.mapConserve(List.scala:166)
....