Low priority implicits issue

gistfile1.scala

def test(m: Magnet): Int = m.i

class Magnet(val i: Int)

object Magnet extends LowerPriorityMagnet {
  implicit def fromUnitWithInt(u: Unit)(implicit i: Int) = new Magnet(i)
}

abstract class LowerPriorityMagnet {
  implicit def fromUnitWithString(u: Unit)(implicit s: String) = new Magnet(s.toInt)
}

implicit val ev = 3

test() == 3 // true

implicit val ev = "3"

test() == 3

// <console>:32: error: not enough arguments for method test: (m: Magnet)Int.
// Unspecified value parameter m.
//              test()
//                  ^