Changing Item Drops

[Epsilith]

I've used other ways of trying but this is the one I could seem to replicate. Doesn't work and seems to crash cuberite

function OnBlockToPickups(a_World, a_Digger, a_BlockX, a_BlockY, a_BlockZ, a_BlockType, a_BlockMeta, a_Pickups)
if (a_Digger ~= nil) then
return false;
end

if (a_BlockType == E_BLOCK_IRON_ORE) then
return true
end

a_Pickups:Clear();

a_Pickups:Add(cItem(E_ITEM_IRON_INGOT));
return true;
end;