custom logger allowing streams and logging to file or screen or both

[archwn]

Dear all,
I would like to create a custom logger which allows logging commands in stream-style, but at the same time the output goes to some file or to the screen (cout) or to both. The code below illustrates the functionality:

#include <iostream>
#include "logger.hpp"
using std::endl;
 
int main()
{
  Log log;
  log.init("out.log");
  log.setLogOutputToFile(true);
  log.setLogOutputToScreen(true);
 
  int i = 10;
  log << "iteration #" << i << endl;
  return 0;
}

Most of the member functions above are trivial to implement. I tried to overload operator<< as follows:

template <typename T>
Log& Log::operator<<( T& os )
{
  if (printToFile_)
  {
    logFile_ << os;
  }
 
  if (printToScreen_)
  {
    cout << os;
  }
 
  return *this;
}
 

After compiling with g++ I get the following errors:

src/main.cpp:17: error: no match for ‘operator<<’ in ‘((Log*)log.Log::operator<< [with T = const char [12]](((const char (&)[12])"iteration #")))->Log::operator<< [with T = int](((int&)(& i))) << std::endl’

or compiling with intel's-icpc

src/main.cpp(17): error: no operator "<<" matches these operands
operand types are: Log << <unknown-type>
log << "iteration #" << i << endl;

Not to mention that we do not only desire to allow "endl" but all manipulators like "std::right, std::left, setw" etc.

Is there something I am doing wrong? Of course there is, but what can I do to get rid of these error messages?

Thank you all for your time,
Archwn.