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POInheritance issues with template classes
 

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    <p>Can anyone figure out a nice way to get the following code to work? (This is, once again, an incredibly simplified way of doing this)</p> <p><pre><code></p> <p>template &lt;class f, class g> class Ptr;</p> <p>class RealBase { };</p> <p>template &lt;class a, class b, class c = Ptr&lt;a,b> > class Base : public RealBase { public: Base(){}; };</p> <p>template &lt;class d, class e> class Derived : public Base &lt;d,e> { public: Derived(){}; void DerivedMethod(){}; }; template &lt;class f, class g> class Ptr { public: Ptr(){}; Ptr(Base&lt;f,g,Ptr&lt;f,g> >* a){in = a;}; Base&lt;f,g,Ptr&lt;f,g> >* operator->() { return in; }; private: Base&lt;f,g,Ptr&lt;f,g> >* in; };</p> <p>typedef Derived&lt;double,double> DDerived;</p> <p>int main() { Base&lt;int,int> b = Base&lt;int,int>(); Derived&lt;double,double> d = Derived&lt;double,double>(); DDerived dd = DDerived(); Ptr&lt;double,double> p(&amp;dd); p->DerivedMethod(); return 1; } </pre></code></p> <p>At the moment the compiler moans because a Base&lt;> doesn't have a DerivedMethod();</p> <p>EDIT</p> <p>I do understand the problem here, my bad for a lack of explanation in the first case (I was in a rush). [This is very cut down code by the way so, yes, for the sake of simplicity I don't have destructors or methods that actually DO anything. Just ignore that, it makes no difference to the problem.]</p> <p>What I need to happen is that an iterator (that isn't detailed here) that deals only with the derived class (D_Derived) need to access a method that is contained within a derived class and not the base class. Simply plonking this method into the base class isn't really an option because this error is going to occur a LOT if I have to do that. (There are about 10 classes built on the real base class, and they all have derived methods of their own. Like 20 of them. Each.)</p> <p>Can anyone think of another way to achieve this functionality?</p>
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