title: How to serialize an array of polymorphic objects to file using Protocol Buffers?
body: <p>Having an array <code>std::vector&lt;BaseClass*&gt;</code> what is the correct way of saving this array to a file using Google's Protocol Buffers library? </p>
  
  <p><code>BaseClass</code> is a base class of hierarchy of classes, it has several sub classes. 
  Is Google's Protocol Buffers even suitable for this purpose or maybe another library would be preferred?</p>