example.cpp

#include <iostream>
using namespace std;
class Foo {
  public:
    ostream* std_out;
    Foo() : std_out(&cerr) {
      std_out->setf(ios::showpoint | ios::left);
    }
    void print() {
      *std_out << 4.5f << endl;
    }
};
Foo x;
int main() {
  x.print();
  return 0;
}