Re: [boost] Are there any interest in a pimpl library?

From: Asger Mangaard (tmb_at_[hidden])
Date: 2005-09-29 04:26:02

>>
>> I'm sorry, but I'm really having a hard time figuring out if you're
>> strickly ironic in your answer or not?
>
> The only thing remotely ironic in what I wrote was WRT the
> one-versus-two-line declaration.  That is, your scheme avoids a
> separate line for the declaration of the impl type, and I was
> noting that it was only marginally better.
>
That I'm glad to hear. I just wanted to make sure.

>> >> >
>> >> >> The only thing my library does is to initialize the forward
>> declared
>> >> >> class, using heap or static memory through policies. Also,
>> provides
>> >> an
>> >
>> > What about pimpl types with non-default constructors?  I can see
>> > an assignment operator taking an impl *, making your proposed
>> > class like a reseatable smart pointer.  That would permit the
>> > client to construct the impl any way necessary and then just hand
>> > it off to your class.
>
> I'd still like to hear what you have in mind here.
>
I actually didn't include this in my initial thoughts. Mainly because
pimpl classes will most often be small structs. However, I'm certainly
very fond of your idea. -I'll include it in my library asap.

>> >> The 'already initialized' check is optimal through a policy. The main
>> >
>> > I take it you mean that your policy can construct the impl
>> > instance when the pimpl is instantiated and then opt to not check
>> > in the member selection operator?  If so, that should probably be
>> > the default mechanism.  The policy you describe should be called
>> > something like, "lazy_creation."
>
> What do you think of this?
>
I fully agree, and will implement it asap.

>> >> I hope this answers your questions.
>> >
>> > It would have been helpful to have listed these things in your
>> > original post.
>
> Here I was pointing out that your initial points omitted a great
> many details that were necessary for us to understand your
> proposal and took many replies to extract.  This, too, was
> prescriptive so that your future messages will be more helpful up
> front.
>

I'm sorry for the lack of information in my initial post, I'll try and
correct this in the future.

So how does this work? Should I now post my library in the vault for peer
reviews, or?

Regards,
Asger Mangaard