Is it possible to store different subclasses in one array?
In C#, we have this example, but how I do that in D?


public class BaseItem{
      public string name = "";
 }

 public class Weapon : BaseItem{
      public int damage = 10;
 }

 public class Potion : BaseItem{
      public int hpRestore = 50;
 }

var GameItems = new List<BaseItem>();
GameItems.Add(new Weapon());
GameItems.Add(new Potion());

On Monday, 13 April 2020 at 01:42:51 UTC, Leonardo wrote:
> Is it possible to store different subclasses in one array?
> In C#, we have this example, but how I do that in D?

Did you try

BaseItem[] GameItems;
GameItems ~= new Weapon();


yet?

On Monday, 13 April 2020 at 01:47:11 UTC, Adam D. Ruppe wrote:
> On Monday, 13 April 2020 at 01:42:51 UTC, Leonardo wrote:
>> Is it possible to store different subclasses in one array?
>> In C#, we have this example, but how I do that in D?
>
> Did you try
>
> BaseItem[] GameItems;
> GameItems ~= new Weapon();
>
>
> yet?

Oh, thanks, this works. Now it seems obvious.
But fitting another question, this case is only representative, if I want to use one method present in only one of these classes like this:

 foreach (ref gi; GameItems)
{
    if (gi == Weapon)
        gi.Attack()
}

How would it be?

On Monday, 13 April 2020 at 04:15:04 UTC, Leonardo wrote:
> On Monday, 13 April 2020 at 01:47:11 UTC, Adam D. Ruppe wrote:
>> On Monday, 13 April 2020 at 01:42:51 UTC, Leonardo wrote:
>>> Is it possible to store different subclasses in one array?
>>> In C#, we have this example, but how I do that in D?
>>
>> Did you try
>>
>> BaseItem[] GameItems;
>> GameItems ~= new Weapon();
>>
>>
>> yet?
>
> Oh, thanks, this works. Now it seems obvious.
> But fitting another question, this case is only representative, if I want to use one method present in only one of these classes like this:
>
>  foreach (ref gi; GameItems)
> {
>     if (gi == Weapon)
>         gi.Attack()
> }
>
> How would it be?

Replying myself...

weapon = cast(Weapon) gi;
if (weapon !is null)
    weapon.Attack()

On Monday, 13 April 2020 at 04:21:48 UTC, Leonardo wrote:
>>
>>  foreach (ref gi; GameItems)
>> {
>>     if (gi == Weapon)
>>         gi.Attack()
>> }
>>
>> How would it be?
>
> Replying myself...
>
> weapon = cast(Weapon) gi;
> if (weapon !is null)
>     weapon.Attack()

can be simplified as:

    if (auto weapon = cast(Weapon) gi)
        weapon.Attack();

On Monday, 13 April 2020 at 05:54:52 UTC, evilrat wrote:
> On Monday, 13 April 2020 at 04:21:48 UTC, Leonardo wrote:
>>>
>>>  foreach (ref gi; GameItems)
>>> {
>>>     if (gi == Weapon)
>>>         gi.Attack()
>>> }
>>>
>>> How would it be?
>>
>> Replying myself...
>>
>> weapon = cast(Weapon) gi;
>> if (weapon !is null)
>>     weapon.Attack()
>
> can be simplified as:
>
>     if (auto weapon = cast(Weapon) gi)
>         weapon.Attack();

Even better. Thanks folks!

On Monday, 13 April 2020 at 05:54:52 UTC, evilrat wrote:
>     if (auto weapon = cast(Weapon) gi)
>         weapon.Attack();

Does the parlor (currently illegal in Dlang)

      if (Weapon w := gi)
          w.Attack();

look nicer or even (currently legal):

      if (Weapon w ._= gi)
          w.Attack();