Complex policies

[anderberg]

Reading about policies in Andrei Alexandrescu's Modern C++
Design, I was wondering about the complexity of policies.

It there a general recommendation that these policies should be
relatively small and simple (compare Create policy in the above
book) or can they be arbitrarily complex? For instance would it
make sense to define a FileParser policy which states how a file
should be parsed? Or should that be deduced further to smaller
components/policies?

Maybe it doesn't matter as long as the policy interface is
followed?

--
anderberg: People are just mutations. Some worse than others.

[Victor Bazarov]

anderberg wrote:

Reading about policies in Andrei Alexandrescu's Modern C++
Design, I was wondering about the complexity of policies.

It there a general recommendation that these policies should be
relatively small and simple (compare Create policy in the above
book) or can they be arbitrarily complex? For instance would it
make sense to define a FileParser policy which states how a file
should be parsed? Or should that be deduced further to smaller
components/policies?

Maybe it doesn't matter as long as the policy interface is
followed?

I think it's the choice you need to make when designing your system.
Nothing in the language says your template arguments need to be simple
or cannot be as complex as you can handle. Whether it makes sense to
subdivide your more complex parts of the system into simpler ones, is
completely up to you (and the group you're working in).

For language-neutral advice on OOD and OOA, try 'comp.object' newsgroup.

V