Is this the proper way to do it?

[Jack]

On Saturday, 13 February 2021 at 09:54:28 UTC, Rumbu wrote:
> On Saturday, 13 February 2021 at 05:52:34 UTC, Jack wrote:
>> I have a base class A, where I make specific operator 
>> depending on the derived class type. Currently I'm using 
>> something like this:
>>
>> c is a class derived from A
>> bool shouldDoX = (cast(X)c) !is null || (cast(Y)c) !is null || 
>> (cast(K)c) !is null ... ;
>>
>> as the number of cast(C) !is null is growing, I'm afraid of 
>> this being a inelegant or even poor performance approach. How 
>> would you do that?
>
> Option 1, reverse the condition, && op will shortcut boolean 
> conditions
>
> bool shouldNotDoX = cast(X)c && cast(Y)c && cast(K)c && ...
>
> Option 2, reverse the condition by testing the classes that are 
> not supposed to "do" it, if you have less classes in that 
> category.
>
> bool shoudldNotDoX = cast(P)c || cast(Q)c

I ended up using virtual functions, this cast and conditions 
would get too big, ugly and messy with time