Re: [Boost-users] Pimpl framework comments/suggestions

Subject: Re: [Boost-users] Pimpl framework comments/suggestions
From: Rob Riggs (rob_at_[hidden])
Date: 2011-04-18 00:47:45

On 04/17/2011 07:10 PM, Clinton Mead wrote:
>
> And if Klass is the interface, won't it need to contain another 
> pointer, which would result in following two pointers instead of one 
> for all method calls?

Who cares? It's a reasonable price for what Pimpl buys you.  The price 
of that encapsulation is a little indirection. With the added benefit 
that it can be used as a plain old value type (no pointer, except the 
one hidden inside).

If that cost is too much to bear, Pimpl isn't the right answer in the 
first place.

I think you might be missing the point about why Pimpl is such a rockin' 
cool idea.  It is an extremely simple mechanism for ensuring ABI 
stability.  If it's no longer dead simple, it completely loses its 
charm; it becomes harder to maintain a stable ABI.  Library writers 
don't want that.