Re: [boost] [Review] GGL review starts today, November 5th

Subject: Re: [boost] [Review] GGL review starts today, November 5th
From: Steven Watanabe (watanabesj_at_[hidden])
Date: 2009-11-22 20:02:57

AMDG

Patrick Horgan wrote:
> Steven Watanabe wrote:
>> FWIW, non-virtual destructors are the norm in Boost.
>> I strongly dislike the idea of having a policy enabling
>> virtual destructors.
> Steven, could you tell me the reason for this?

There aren't a lot of virtual function in Boost either.
In ggl, the only virtual functions I see are in exception classes.

> I have always thought that if you had virtual methods, you should have 
> a virtual destructor since the derived class has something different 
> about it and if being destructed via a reference or pointer to base, 
> the wrong thing could happen without a virtual destructor!  Educate me 
> please.  I've never heard of any reason to avoid a virtual destructor 
> if you already had virtual methods.  Obviously I'm missing something 
> about something I thought I understood.

I don't think so.  If you're using virtual functions in the
normal OO way, a virtual destructor almost always
makes sense.  (The use of virtual in Boost.Exception
is somewhat different.  virtual is being used as an
implementation detail to separate a fragment of the
interface of a concrete type from the rest of the type
in order to minimize dependencies.  It isn't being used
for polymorphism at all)

In Christ,
Steven Watanabe