Object onto streams

• Complex objects may have a complex output procedure
• Example: we want to be able to say cout « theTimeStamp « endl; and get
  Thu Sep 7 12:23:11 2006 as output
• Solution: overload the « operator
  

  std::ostream& operator«(std::ostream& s, TimeStamp& t)
  throw (TimeStampException);

#include <ctime>
std::ostream& operator«(std::ostream& s, TimeStamp& t)
throw (TimeStampException) {
using namespace std;
time_t theTime = (time_t) t.get();
char* buffer;
try {
buffer = ctime(&theTime);
} catch (...) {
cerr « "TimeStamp::updateTimeStamp(): "
"couldn't print system time" « endl;
throw TimeStampException();
}
buffer[strlen(buffer) - 1] = ' $\backslash$ 0';
s « buffer;
return s;
}