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    <p>Here's something I do often, it's not pretty, but it's simple and useful.</p> <p>I often work with template containers that implement an interface, imagine something like</p> <pre><code>template&lt;class T&gt; class MyVector : public ContainerInterface ... </code></pre> <p>Where ContainerInterface has basic useful stuff, but that's all. If I want a specific algorithm on vectors of integers without exposing my template implementation, it is useful to accept the interface objects and dynamic_cast it down to MyVector in the implementation. Example:</p> <pre><code>// function prototype (public API, in the header file) void ProcessVector( ContainerInterface&amp; vecIfce ); // function implementation (private, in the .cpp file) void ProcessVector( ContainerInterface&amp; vecIfce) { MyVector&lt;int&gt;&amp; vecInt = dynamic_cast&lt;MyVector&lt;int&gt; &gt;(vecIfce); // the cast throws bad_cast in case of error but you could use a // more complex method to choose which low-level implementation // to use, basically rolling by hand your own polymorphism. // Process a vector of integers ... } </code></pre> <p>I could add a Process() method to the ContainerInterface that would be polymorphically resolved, it would be a nicer OOP method, but I sometimes prefer to do it this way. When you have simple containers, a lot of algorithms and you want to keep your implementation hidden, dynamic_cast offers an easy and ugly solution.</p> <p>You could also look at double-dispatch techniques.</p> <p>HTH</p>
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    1. POWhat are some 'good use' examples of dynamic casting?
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