Listing 8: Template class indirect_array

        // MACROS
#define IOP(RHS) \
    size_t L = Totlen(); \
    for (size_t I = 0; I < L; ++I) \
        Ptr[Indir(I)] RHS;
#define IOP2(RHS) \
    size_t N = L.Totlen(); \
    for (size_t I = 0; I < N; ++I) \
        L.Data(L.Indir(I)) RHS;

        // TEMPLATE CLASS indirect_array
template<class Ty>
    class indirect_array {
public:
    typedef Ty value_type;
    void operator=(const valarray<Ty>& R) const
        {IOP(= R[I]); }
    void operator=(const Ty& R)
        {IOP(= R); }
    Ty& Data(size_t I) const
        {return (Ptr[I]); }
    size_t Indir(size_t I) const
        {return (Iarr[I]); }
    size_t Totlen() const
        {return (Iarr.size()); }
private:
    friend class valarray<Ty>;
    indirect_array(const Sizarray& Ia, Ty *Pd)
        : Iarr(Ia), Ptr(Pd) {}
    Sizarray Iarr;
    Ty *Ptr;
    };

        // indirect_array MEMBER TEMPLATE OPERATORS
template<class Ty> inline
    void operator*=(const indirect_array<Ty>& L,
        const valarray<Ty>& R)
    {IOP2(*= R[I]); }
// etc.
//End of File