Re: [boost] Re: Loki SmartPtr study: Policy orthogonality issues

From: Andrei Alexandrescu (andrewalex_at_[hidden])
Date: 2002-01-07 15:14:25

> The difficulty with using the framework to mediate the communication via
> forwarding functions is that communication is limited to exactly those
> forwarding functions and now others. And they are still there even when
not
> needed.  The forwarding function also represent additional complexity.

The idea is that the framework is written by the library designer, and
policies can be written by both the library designer and the library user.
In particular, an important goal of Loki::SmartPtr was to make typical
user-defined policies (COM/CORBA ownership, custom checkers, etc.) easy to
implement. Also, SmartPtr can be fairly intricate because it is designed and
implemented only once.

That's why I find the design in which SmartPtr is an orchestrator of various
policies a natural one. It also was one that satisfied its users.

What practical problem requires policies to communicate with each other?

Andrei