void add_item(const item_def &item);

void explore_discoveries::add_item(const item_def &i)
{
    if (is_stackable_item(i))
    {
        // Try to find something to stack it with.
        for (int j = 0, size = items.size(); j < size; ++j)
        {
            if (items_stack(i, items[j].thing))
            {
                items[j].thing.quantity += i.quantity;
                items[j].name = item_name(items[j].thing, DESC_NOCAP_A);
                return;
            }
        }
    }
    items.push_back( named_thing<item_def>(item_name(i, DESC_NOCAP_A), i) );
}

    items.push_back( named_thing<item_def>(item_name(i, DESC_NOCAP_A), i) );

    add_item(i);

bool is_stackable_item( const item_def &item );

static bool is_stackable_item( const item_def &item );

static bool is_stackable_item( const item_def &item )

bool is_stackable_item( const item_def &item )

        || item.base_type == OBJ_GOLD

    if (item1.base_type == OBJ_GOLD)
        return (true);