Re: Constructors and virtual inheritance...

From:
"Ivan Novick" <ivan@0x4849.net>
Newsgroups:
comp.lang.c++.moderated
Date:
28 Nov 2006 23:38:44 -0500
Message-ID:
<1164766121.971604.205630@j72g2000cwa.googlegroups.com>
DeCaf wrote:

What is the recommended way of handling this?
I post an example below that illustrates what I mean if the text above
did not quite clarify it:


The important question is how much of the code are you free to modify.
The relationships you are creating appear to be non-elegant. If we
have freedom to make some changes this would be much cleaner:

// concrete class with functionality we want to inherit
class Node
{
   public:
   Node(const std::string &id) : mId(id)
   {
     std::cout << "Node with id " << id << " created\n";
   }
   private:
    std::string mId;
};

// abstract interface
class DependerNode
{
public:
   virtual void bar() = 0;
};

// abstract interface
class DependeeNode
{
public:
   virtual void bar2() = 0;
};

// inherit the concrete functionality and implement two abstract
interfaces
class ExpressionNode : public DependerNode, public DependeeNode, public
Node
{
public:
   ExpressionNode(const std::string &id) : Node(id) {}
   void bar() {}
   void bar2() {}
};

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