stl::list modified erase

Hi,

I am using multiple stl::list s of different types.

Now I want to write a function

list<type>::iterator s_erase(list<type> l, list<type>::iterator it)

that takes an iterator and deletes the element it is pointing add, and 
returns the iterator pointing to the predecessor of the erased element.

like this:

return l.erase(it)--;

But I want this to work for any contained type. For clarification:
I have theses lists:

list<c****p> ****ps;
list<cProjectile> Projectiles;
list<cAsteroid> Asteroids;

And I want my function to work on all of these lists. Is that possible?

Regards
Philip