Arbitrary Query object

query.scala

trait Query[-A,+B,Cont[_] <: Iterable[_]] extends (A => Try[Cont[B]]){
  self =>
  
  def apply(arg0: A) = Try(unsafe(arg0))
  
  protected def unsafe(arg0: A): Cont[B]
  
  def map[C](f: B => C) = new Query[A,C,Cont]{
    def unsafe(arg0: A) = self unsafe arg0 map f
  }
  
  def filter(p: B => Boolean) = new Query[A,B,Cont]{
    def unsafe(arg0: A) = self unsafe arg0 filter f
  }
  
  def filterNot(p: B => Boolean) = filter(!p(_))
}