Use references here:
```cpp
virtual bool OnPreEnchanting            (cPlayer & a_Player, cWeightedEnchantment & a_PossibleEnchantments, cItem & a_Item) = 0;
virtual bool OnPostEnchanting           (cPlayer & a_Player, cEnchantments & a_EnchantmentsChosen, cItem & a_Item, int a_Levels) = 0;
```
and naturally everywhere this leads to.