alpar@1001: // -*- mode:C++ -*-
alpar@1001: 
alpar@1001: //////////////////////////////////////////////////////////////////////
alpar@1001: // Named "function" parameters
alpar@1001: //////////////////////////////////////////////////////////////////////
alpar@1001: 
alpar@1001: class named_fn 
alpar@1001: {
alpar@1001:   int _id;
alpar@1001:   double _val;
alpar@1001:   int _dim;
alpar@1001:   
alpar@1001:   public:
alpar@1001:   named_fn() : _id(0), _val(1), _dim(2) {}
alpar@1001:   named_fn& id(int p)     { _id  = p ; return *this; }
alpar@1001:   named_fn& val(double p) { _val = p ; return *this; }
alpar@1001:   named_fn& dim(int p)    { _dim = p ; return *this; }
alpar@1001: 
alpar@1001:   ~named_fn() {
alpar@1001:     //Itt van maga az algoritmus
alpar@1001:   }
alpar@1001: };
alpar@1001: 
alpar@1001: //Hasznalat:
alpar@1001: //named_fn().id(3);
alpar@1001: //named_fn().id(3).val(2);
alpar@1001: //named_fn().dim(4).id(3);
alpar@1001: 
alpar@1001: 
alpar@1001: //////////////////////////////////////////////////////////////////////
alpar@1001: // Named class template parameters (A)
alpar@1001: //////////////////////////////////////////////////////////////////////
alpar@1001: 
alpar@1001: template<class A=int,class B=double>
alpar@1001: class Named_T
alpar@1001: {
alpar@1001: public:
alpar@1001: 
alpar@1001:   typedef A Atype;
alpar@1001:   typedef B Btype;
alpar@1001: 
alpar@1001:   template <class T> class SetAType : public Named_T<T,Btype> { };
alpar@1001:   template <class T> class SetBType : public Named_T<Atype,T> { };
alpar@1001: };
alpar@1001: 
alpar@1001: // Named_T<>::SetAType<double>::SetBType<double>
alpar@1001: 
alpar@1001: //////////////////////////////////////////////////////////////////////
alpar@1001: // Named class template parameters (A)
alpar@1001: //////////////////////////////////////////////////////////////////////
alpar@1001: 
alpar@1001: struct _NTR 
alpar@1001: {
alpar@1001:   typedef int Atype;
alpar@1001:   typedef double Btype;
alpar@1001: };
alpar@1001: 
alpar@1001: template<class TR=_NTR>
alpar@1001: class Named_TR
alpar@1001: {
alpar@1001: public:
alpar@1001: 
alpar@1001:   typedef typename TR::Atype Atype;
alpar@1001:   typedef typename TR::Btype Btype;
alpar@1001: 
alpar@1001:   Atype a;
alpar@1001:   Btype b;
alpar@1001:   
alpar@1001:   template <class T>
alpar@1001:   struct ATR : public TR {
alpar@1001:     typedef T Atype;
alpar@1001:   };
alpar@1001: 
alpar@1001:   template <class T>
alpar@1001:   class SetAType : public Named_TR<ATR<T> > { };
alpar@1001: 
alpar@1001:   template <class T>
alpar@1001:   struct BTR : public TR {
alpar@1001:     typedef T Btype;
alpar@1001:   };
alpar@1001:   template <class T>
alpar@1001:   class SetBType : public Named_TR<BTR<T> > { };
alpar@1001: 
alpar@1001:   Named_TR() {};
alpar@1001:   Named_TR<TR> &setA(Atype _a) { a=_a; return *this;}
alpar@1001:   Named_TR<TR> &setB(Btype _b) { b=_b; return *this;}
alpar@1001: 
alpar@1001:   void run() {
alpar@1001:     // itt az algoritmus
alpar@1001:   }
alpar@1001: 
alpar@1001:   //////////////////////////////////////////////////////////////////////
alpar@1001:   template<class T>
alpar@1001:   SetAType<T> SETA(T t) { SetAType<T> r; r.a=t; r.b=b; return r;}
alpar@1001:   template<class T>
alpar@1001:   SetBType<T> SETB(T t) { SetBType<T> r; r.a=a; r.b=t; return r;}
alpar@1001: };
alpar@1001: 
alpar@1001: // Hasznalat:
alpar@1001: // 1.
alpar@1001: //   Named_TR<>::SetAType<double> nt;
alpar@1001: //   Named_TR<>::SetBType<double>::SetAType<double> nt2;
alpar@1001: //   nt2.setA(5).setB(6).run();
alpar@1001: // 2.
alpar@1001: //   double x;
alpar@1001: //   Named_TR<>().SETA(5.2).SETB(x).run();
alpar@1001: // 3. 
alpar@1001: //   struct MyTr : public _NTR { typedef float Btype; };
alpar@1001: //   int main() 
alpar@1001: //   {
alpar@1001: //     Named_TR<MyTr> d2; d2=d2;
alpar@1001: //   }
alpar@1001: 
alpar@1001: 
alpar@1001: // Sajnos ezt csak a fuggvenyen kivul lehet deklaralni:
alpar@1001: struct MyTr : public _NTR { typedef float Btype; };
alpar@1001: 
alpar@1001: typedef Named_T<> Named_TN;
alpar@1001: 
alpar@1001: int main()
alpar@1001: {
alpar@1001: 
alpar@1001:   Named_T<> a;a=a;
alpar@1001:   Named_T<>::SetAType<double> b;b=b;
alpar@1001:   Named_T<>::SetAType<double>::SetBType<int> c;c=c;
alpar@1001: 
alpar@1001:   Named_TR<> a2;a2=a2;
alpar@1001:   Named_TR<>::SetAType<double> b2;b2=b2;
alpar@1001:   Named_TR<>::SetAType<double>::SetBType<int> c2;c2=c2;
alpar@1001: 
alpar@1001:   //De igy is lehet:
alpar@1001:   Named_TR<MyTr> d2; d2=d2;
alpar@1001: 
alpar@1001:   named_fn().id(3);
alpar@1001:   named_fn().id(3).val(2);
alpar@1001:   named_fn().dim(4).id(3);
alpar@1001: 
alpar@1001:    Named_TR<>::SetAType<double> nt;
alpar@1001:    Named_TR<>::SetBType<double>::SetAType<double> nt2;
alpar@1001:    nt2.setA(5).setB(6).run();
alpar@1001: 
alpar@1001:    double x;
alpar@1001:    Named_TR<>().SETA(5.2).SETB(x).run();
alpar@1001: }
alpar@1001: