Question

When looking at some existing code for a web server, I see that there’s a main.cc file and another server.h and server.cc pair for the server class.

// main.cc
#include "server.h"
int main() {
  foo::server = new foo::Server();
  server->Serve();  // runs forever
}

// server.cc
namespace foo {
  Server *server;

  // class member definitions ...
}

Is there a good reason not to just define foo::Server *server in main?

What are the pros and cons of this coding style?

Answer 1

EDIT

For maintenance. It’s intuitive that you have the definition of foo::server in server.cc. If you only have one variable, the benefit is not directly visible. But say you have dozens of variables. With this style, you know exactly where to look for the definition.