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From: Jeff Garland (jeff_at_[hidden])
Date: 2006-08-24 10:54:58


Julio M. Merino Vidal wrote:
> Hello everybody,
>
> At the moment, some objects in the preliminary Boost.Process library
> are only constructed internally by the library. Examples of these
> include 'status' instances, created by calls to 'child::wait', and
> instances of 'child', created by 'launcher::start'. This is currently
> done by declaring friendship among the related classes (well, not
> exactly, but almost).
>
> I believe this is suboptimal because it prevents extensibility.
> Consider a user that wants to create his own Launcher implementation.

What would be the motivation for providing this?

> His code is required to return a new 'child' object. But, oh! He
> cannot currently create it because the constructor is private and his
> launcher class is not a friend of the provided 'child'. Of course, he
> could implement his own 'child' -- and in turn implement his own
> 'status'. Ouch.
>
>...snip details...
>
> I'm open to other suggestions.

I guess my thought is that if you want extensibility, just make the
constructors public and move on. That's the cleanest and easiest way...

HTH,

Jeff


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