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    <p>I think you have a bit of a misunderstanding of CRTP. It is not a plug in replacement for virtual dispatch. In your case, IBridge has no virtual dispatch, so calling IBridge->LoadDriver will always give you the default base class implementation, regardless of the underlying derived class. If you want a generic interface, you need some kind of virtual dispatch. CRTP is just a way of avoiding virtual dispatch in cases where it is not necessary, for example when a base class member function calls in to other virtual functions.</p> <p>If you want to avoid virtual dispatch completely in you case, you can not completely decouple the client from the Bridge, you would need to template Client on Bridge which doesn't really give you any advantage over just templating on Derived.</p> <p>Here's a shot at doing what you want. It assumed that you pass some generic pointer through IBridge, which Bridge uses CRTP to interpret and pass down to BridgeImpl. Obviously, you've abandoned all hope of type safety on the arguments at this point.</p> <pre><code>class IBridge { virtual void LoadDriver(void *) = 0; }; template &lt;typename Impl&gt; class Bridge : public IBridge { void LoadDriver(void * v) override { static_cast&lt;Impl*&gt;(this)-&gt;LoadDriverImpl(*static_cast&lt;Impl::arg_type *&gt;(v)); } }; class BridgeImpl : public Bridge&lt;BridgeImpl&gt; { typedef std::string arg_type; void LoadDriverImpl(const std::string &amp; s){ /*...*/ } }; </code></pre>
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    1. POHow to use Curiously Recurring Template Pattern for Bridge Pattern?
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    1. COOkay, I think I now understand the relevance of virtual dispatch with this problem, IBridge::LoadDriver isn't being "overridden" by Bridge::LoadDriver ... The solution that I have been trying to avoid is using a static function pointer of some sort to link the two. I am /really/ trying to avoid using RTTI and dynamic casts, which is why I am using CRTP in the first place. What would you recommend? Thanks for your help.
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    2. COYou don't need RTTI/dynamic casts for virtual dispatch. From the example you gave, vanilla virtual dispatch i.e. Derived inherits from IBridge directly, which has a virtual LoadDriver, is probably the best solution. If there is more complexity in the member function calls, you might consider using CRTP at a lower level i.e. IBridge has a virtual LoadDriver, which Bridge overrides and calls a non-virtual LoadDriverImpl on the Derived classes using CRTP (This makes no sense on it's own, but maybe would in a more complex use case)
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    3. COThe entire context is that the Bridge API is in the Framework Tier, (library), consumed by an Application tier, (lib), consumed by a Client tier, (.exe)... The Client tier provides BridgeImplementation : public Bridge<BridgeImplementation>, public IBridgePart .. at run-time, the Application Tier calls a Framework Tier based Service Locator to go find the other end of the Bridge implemented in the Client Tier. The Application and Framework Tiers know nothing about the implementations except that an IBridgePart::ICommandPattern will be returned by the BridgeServiceLocator. HTH
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