Path: utzoo!utgpu!jarvis.csri.toronto.edu!rutgers!cs.utexas.edu!wasatch!mailrus!ulowell!masscomp!guest
From: guest@masscomp.UUCP (Mr Guest)
Newsgroups: comp.lang.c++
Subject: constructors for virtual base classes
Message-ID: <1429@masscomp.UUCP>
Date: 5 Jul 89 16:26:08 GMT
Reply-To: loepere@westford.ccur.com (Keith Loepere)
Organization: MASSCOMP - Westford, Ma
Lines: 30


Consider the following template for a set of classes involving virtual
base classes with constructors.

class common
{
  common () {}
};

class virtual_1 : virtual public common
{
  virtual_1 () : common () {}
};

class virtual_2 : virtual public common
{
  virtual_2 () : common () {}
};

Each of the two classes derived from common has their own constructor
which "call" the constructor for their base class.  Now derive a class
from both of these:

class both : public virtual_1, public virtual_2
{
  both () : virtual_1 (), virtual_2 () {}
};

It seems to me that the constructor for "common" will be called twice.
What am I doing wrong? - Keith