Assocative array lookup for object

[Salih Dincer]

On Wednesday, 12 April 2023 at 04:57:58 UTC, Salih Dincer wrote:
> I think you want to do an encapsulation like below.
>
> ```d
>   auto opIndex(string key)
>     => *(key in data);
> ```

I made a little mistake and I'll fix it before someone rub nose 
in it :)

```d
   auto opIndex(string key) {
     if(auto ret = key in data)
     {
       return *ret;
     }
     return null;
   }

   assert(handler["D Lang"] == &foo);
   assert(handler["null"] is null);
```

SDB at 79