letting D generate functions that look alike

[Saaa]

As the subject says, I would like D to generate functions from a template or 
something.

I have a (elaborate) function which I have to copy a few times with only 
minor changes.
I could make the function variadic, but this would be slower.
Can I let D create the functions for me?

The changes between the functions aren't complexer than:

int add_1(int num){
  int i;
  i=num+1;
  return i;
}

int add_2(int num){
  int i;
  i=num+2;
  return i;
}