R my_func.cpp(R a){ return a*3.0;}
#define R float#include "my_func.cpp"#define R double#include "my_func.cpp"
#ifdef _USE_FLOATtypedef float value_type#else#ifdef _USE_DOUBLEtypedef double value_type#endif#else#error value type undefined#endif#endifvalue_type MyFunc(const value_type & a);