title: Serialization of STL unordered_map
body: <p>I have a program which uses an unordered map with this definition:</p>
  
  <pre><code>unordered_map&lt;const char*, vector&lt;pair&lt;int, int&gt; &gt;, function&lt;unsigned int (const char *str)&gt; &gt; myMap(30000, hashing);
  </code></pre>
  
  <p>where hashing is a function used for, well, hashing keys. My problem is -> how to serialize this kind of structure and deserialize it afterwards? I really need that, and to be fast and efficient as possible. I have been reading about boost libraries, but I don't understand much how to use them with this kind of stuff. I know there is some boost library for unordered maps, but, obviously I'm doing something wrong with it and the compiler throws a lot of errors. Can someone give me an example code that works on how to serialize this? Thanks.</p>