parameter passing - C++, pointer to a function as a new type -

in c++ 2003, typedef may used on complete types. hence, not allow create pointer function , generic t type:

template <typename t> typedef t(*f_function)(t, t, t); 

is there way how evade issue in c++ 2003 or in c++0x using syntax

using (*f_function)(t, t, t); // 

i use pointer function fff class member

template <typename t> class { public:     f_function fff;      a() {fff = null;}     a( f_function pf){fff = &pf;} };  template <typename t> t f1(t x, t y, t z) {   return x + y + z;}  template <typename t> t f2(t x, t y, t z) {   return x - y - z;} 

and initialize value in constructor. subsequently:

int main() { <double> a(f1); double res = a.getx(1.1, 2.2, 3.3); } 

is construction safe? there other way how solve problem? help.

you may use alias template (c++11) declaration:

template <typename t> using f_function = t(*)(t, t, t); 

example:

http://coliru.stacked-crooked.com/a/5c7d77c2c58aa187

#include <iostream> #include <string> #include <array>  template <typename t> using f_function = t(*)(t, t, t);  template <typename t> class { public:     f_function<t> fff;      a() {fff = null;}     a( f_function<t> pf){fff = pf;} };  template <typename t> t f1(t x, t y, t z) {   return x + y + z;}  template <typename t> t f2(t x, t y, t z) {   return x - y - z;}  int main() { <double> a(f1); double res = a.fff(1.1, 2.2, 3.3); std::cout << res; }