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POMultiple inheritance specify desired virtual function without redfining it
 

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    <p>I want to know if there is a way to specify that in multiple inheritence, one of the base-classes virtual functions becomes the single virtual definition. They only way I see to do this is by writing an explicit definition of this function in the derived class and explicitly call one of the base classes. This is cumbersome, and I was hoping <code>using</code> might help, but it doesn't.</p> <p>For example, in the below code, I have to define a <code>C::value</code> even though I just wish to forward to the class B version. Is there not a simpler way?</p> <pre><code>#include &lt;iostream&gt; using namespace std; struct A { virtual char const * value() const { return "A"; } }; struct B { virtual char const * value() const { return "B"; } }; class C : public A, public B { public: //using B::value; virtual char const * value() const { return B::value(); } }; int main() { C obj; cout &lt;&lt; obj.value() &lt;&lt; endl; A * ptr = &amp;obj; cout &lt;&lt; ptr-&gt;value() &lt;&lt; endl; } </code></pre> <p>Some notes:</p> <ul> <li>in this particular case virtual inheritance of class A is not an option for Class B -- I need a proper construction chain down to the base</li> <li>In theory struct B could also be used unrelated to A, but that is not the case here (in case that provides other options)</li> <li><code>value</code> may be marked as pure virtual if that somehow helps, but I don't believe it does.</li> <li>there are other classes which derive from A but not B</li> <li>to be clear, however "func" is called on C, through any type pointer, must result in "B"</li> </ul> <p>I suspect the answer might be "No", but some confirmation would be good. It feels like the language should support this pattern.</p>
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    1. COWhat is the output of the above program?
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    2. COMaybe you can add a dummy 'node' to the inheritance tree (e.g. `DummyC` which virtually inherits from `A`, and `C` which inherits from `DummyC` and `B`). Not sure it's possible, but take a look here: http://stackoverflow.com/questions/3310910/method-resolution-order-in-c and see if this helps.
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    3. CO@Bingo, the above program outputs "B" and "B" because I override the function. If you don't do this, just do the `using` declartion you will get "B" and "A".
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