Perfectly bad example

This is the example that I wasted the morning on

 
struct count { 

  count(int id) : id(id) { }

  void operator()() {
   for (int i = 0; i < 10; ++i) {
      boost::mutex::scoped_lock lock(io_mutex);
      std::cout << id << ": " << i << std::endl;
   }
 }

int id; 
};

This example came with no explanatory text. Not only are there advanced C++ goodies like initialization lists and functors, the guy uses the c++ idiom where same identifier is used for a formal parameter and a field variable. The compiler gives you a clever wink when you use code like

id(id) { }

and sets the field "id" to the argument supplied in the constructor "id".

This example should have the comment

/* If you are reading this example, you are too ignorant to use my code. Go away. */