title: How to transform fields during deserialization using Serde?
body: <p>I'm using Serde to deserialize an XML file which has the hex value <code>0x400</code> as a string and I need to convert it to the value <code>1024</code> as a <code>u32</code>.</p>
  
  <p>Do I need to implement the <code>Visitor</code> trait so that I separate 0x and then decode 400 from base 16 to base 10? If so, how do I do that so that deserialization for base 10 integers remains intact?</p>