"Thorsten Ottosen" <nesotto@cs.auc.dk> writes:
"David Abrahams" <dave@boost-consulting.com> wrote in message news:uk6mo2ylf.fsf@boost-consulting.com... | "Thorsten Ottosen" <nesotto@cs.auc.dk> writes: | | > A "value object" implies something that behaves as an int; a | > "polymophic object" implies something that needs to allocated | > dynamically and which has virtual functions. | | A polymorphic object doesn't need to be allocated dynamically.
if you want it to act polymophic you have to.
int f(Base& b) { return b.some_virtual_function(); // acts polymorphically } Derived d; // not dynamically allocated. int x = f(d);
| > trying to make a polymorphic object behave like a value object is | > confusing a best. | | Who does it confuse? Pimpl is a commonly used and well understood | pattern for doing just that.
Pimpl is an ugly hack for compilation firewalls.
It's a standard way to hide polymorphic behavior behind a statically-typed interface. Arguing that it is an ugly hack is just a distraction from the point at hand, so I'll ask again: Who is confused by Pimpl? -- Dave Abrahams Boost Consulting www.boost-consulting.com