[boost] Re: is_abstract_base<T> ?

From: Joe Gottman (jgottman_at_[hidden])
Date: 2003-01-24 18:50:33

"Robert Ramey" <ramey_at_[hidden]> wrote in message
news:01C2C3B8.367B8A60_at_226-146.adsl2.netlojix.net...
> Is there such a thing as is_abstract_base<T> similar to is_polymorphic<T>
?
>
> Is such a thing possible?  I could use it but have been unable to figrure
> out how to do it.
>

   I assume that you expect is_abstract_base<T> to return true if and only
if it is it is impossible to create an object of type T, and you must create
an object of some subclass of T instead.  One problem with this is that
there are two very different ways of requiring the user to derive from T.
The most common way is to declare type T with one or more pure virtual
member functions.  The other way is to declare T so that all its
constructors are protected, as in boost::noncopyable.

Joe Gottman