#include <iostream>
#define DUMPSTR_WNAME(os, name, a) \
do { (os) << (name) << " is value " << (a) << std::endl; } while(false)
#define DUMPSTR(os, a) DUMPSTR_WNAME((os), #a, (a))
#define DUMP(a) DUMPSTR_WNAME(std::cout, #a, (a))
struct S {
int a1;
float a2;
std::string a3;
std::ostream& dump(std::ostream& os)
{
DUMPSTR(os, a1);
DUMPSTR(os, a2);
DUMPSTR(os, a3);
return os;
}
};
int main()
{
S s = { 3, 3.14, " 03.1415926" };
s.dump(std::cout);
DUMP(s.a1);
DUMP(s.a2);
DUMP(s.a3);
return 0;
}