text: class put_ndx_val_wf
  {
  private:
    stapl::stream<ofstream> m_zout;
  public:
    put_ndx_val_wf(stapl::stream<ofstream> const& zout)
      : m_zout(zout)
    { }
  
    typedef void result_type;
    template <typename Ref1, typename Ref2>
    result_type operator()(Ref1 pos, Ref2 val) {
      m_zout << "[" << pos << "]= " << val <<  "\n";
    }
  
    void define_type(stapl::typer& t) {
      t.member(m_zout);
    }
  };
  