namespace hpx {
  namespace parallel {
    namespace v1 {
      template<typename ExPolicy, typename InIter, typename OutIter, 
               typename F> 
        unspecified transform(ExPolicy &&, InIter, InIter, OutIter, F &&);
      template<typename ExPolicy, typename InIter1, typename InIter2, 
               typename OutIter, typename F> 
        unspecified transform(ExPolicy &&, InIter1, InIter1, InIter2, OutIter, 
                              F &&);
    }
  }
}