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    <p>Can you not have a root Container class that contains elements:</p> <pre><code>template &lt;typename T&gt; class Container { public: // You'll likely want to use shared_ptr&lt;T&gt; instead. virtual void push(T *element) = 0; virtual T *pop() = 0; virtual void InvokeSomeMethodOnAllItems() = 0; }; template &lt;typename T&gt; class List : public Container&lt;T&gt; { iterator begin(); iterator end(); public: virtual void push(T *element) {...} virtual T* pop() { ... } virtual void InvokeSomeMethodOnAllItems() { for(iterator currItem = begin(); currItem != end(); ++currItem) { T* item = *currItem; item-&gt;SomeMethod(); } } }; </code></pre> <p>These containers can then be passed around polymorphically:</p> <pre><code>class Item { public: virtual void SomeMethod() = 0; }; class ConcreteItem { public: virtual void SomeMethod() { // Do something } }; void AddItemToContainer(Container&lt;Item&gt; &amp;container, Item *item) { container.push(item); } ... List&lt;Item&gt; listInstance; AddItemToContainer(listInstance, new ConcreteItem()); listInstance.InvokeSomeMethodOnAllItems(); </code></pre> <p>This gives you the Container interface in a type-safe generic way.</p> <p>If you want to add constraints to the type of elements that can be contained, you can do something like this:</p> <pre><code>class Item { public: virtual void SomeMethod() = 0; typedef int CanBeContainedInList; }; template &lt;typename T&gt; class List : public Container&lt;T&gt; { typedef typename T::CanBeContainedInList ListGuard; // ... as before }; </code></pre>
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    1. COThat is what I was thinking. The only issue is that Item is essentially an empty class. As far as I can tell, I can place no restrictions on what specifically is stored in the container, thus there really isn't a common interface I can extract out. But perhaps that isn't so bad.
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    2. COAlso.. I don't think you can have virtual functions in template. Another major problem ;)
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    3. COYou can have virtual functions in a template.
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