[Biococoa-dev] why placeholder classes was: BCSequence class cluster

Koen van der Drift kvddrift at earthlink.net
Sun Jan 9 09:51:07 EST 2005

On Jan 9, 2005, at 2:15 AM, Charles PARNOT wrote:

> 5. Then what do I do?
> You can't make BCSequenceProtein.h public, you have to create a fake 
> placeholder class, say BCSeqProtein, that will be public, with the 
> right set of methods in the header. The user only knows about this 
> public header that does not inherit from BCSequence. So when using 
> that header, you get a compiler warning if you call -complement.
> However, under the hood, when you alloc such an object, you really get 
> a BCSequenceProtein object, which hooks your object back into the 
> class cluster at runtime.
> I am kind of hoping that you were mostly missing points 1-4. So step 5 
> might still need some explanations... And step 5 might certainly have 
> other answers.
> should't you be sleeping??? (I hope this email helps;-)

Thanks Charles, I understand now why you need a placeholder. However, I 
am not certain why BCSequenceProtein.h should be public. I still don't 
like the idea of having the possibility of the user to use the 

And yes, I got some sleep.

- Koen.

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