Is it possible to implement operators as ordinary functions?

[data pulverizer via Digitalmars-d-learn]

I was wandering if it possible to implement operators as ordinary 
functions instead of as member functions of a class or struct for 
example something like this:

```
import std.stdio: writeln;
struct Int{
  int data = 0;
}

Int opBinary(string op)(Int x1, Int x2)
{
  static if((op == "+") || (op == "-") || (op == "*") || (op == 
"/"))
  {
    int ret;
    mixin("ret = x1.data " ~ op ~ " x2.data");
    return ret;
  }else{
    static assert(0, "Operator unknown.");
  }
}

void main()
{
  Int x = Int(1);
  Int y = Int(2);
  writeln("Output: ", x + y);
}

```