LUA_FUNCTION( add )
{
	int a, b;

	a = Lua->GetNumber();
	b = Lua->GetNumber();

	Lua->Push( a + b );

	return 1;
}

// Somewhere in the initialization code
Lua->GetGlobal( "math" );
Lua->Push( "add" );
Lua->Push( add );
Lua->SetField();