On 10 April 2013 17:01, Paulo Pinto <pjmlp@progtools.org> wrote:

On Wednesday, 10 April 2013 at 06:03:08 UTC, Manu wrote:

[...]

I do use virtual functions, that's the point of classes. But most functions
are not virtual. More-so, most functions are trivial accessors, which
really shouldn't be virtual.
OOP by design recommends liberal use of accessors, ie, properties, that
usually just set or return a variable. Wen would you ever want @property
size_t size() { return size; } to be a virtual call?

Yes, if you want to change its behavior in a derived class.

That really shouldn't be encouraged. Give me an example?

One nice feature of properties is that you can trigger actions when assigning/reading from properties.

That doesn't make the property virtual, that makes the virtual that the property calls virtual. You can't have a derived class redefining the function of a trivial accessor. If it has a side effect that is context specific, then it would call through to a separate virtual. And this would be a controlled and deliberate case, ie, 1 in 100, not the norm.

This is very used in OO GUI and DB code in other languages.

I know, it's an abomination, and the main reason OOP is going out of fashion.

Can you demonstrate a high level class, ie, not a primitive tool, but the
sort of thing a programmer would write in their daily work where all/most
functions would be virtual?

I have lots of code from JVM and .NET languages with such examples.

OO code in the enterprise world is a beauty in itself, regardless of the language.

That's not an exampe. I want to see a class where every function SHOULD be overloaded... That sounds like a nightmare, how can anyone other than the author ever expect to understand it? The fewer and more deliberately controlled the virtuals, the better, by almost every measure I can imagine.