title: What is the best ASCII char to separate a string?
body: <p>I work on a system on which customer can send me unicode string encoded as utf-8. at some point, I pack/serialize (C++) whose data using a kind of comma separated list like:</p>
  
  <pre><code>fieldName:value,other fieldname:value, etc....
  </code></pre>
  
  <p>that string is goind out of a process andif catched by a python script to extract a dictionnary:</p>
  
  <pre><code> {"fieldName":"value", etc..... }
  </code></pre>
  
  <p>To extract that I use a simple regex <code>re.compile(ur"(.*?):(.*?)(?:,|$)", re.UNICODE)</code>.
  But I know that users can use <code>,</code> and <code>:</code> in the string they send so I'm search for the best ASCII code I could use at C++ level to replace the comma I use for now ?</p>
  
  <p>Is <code>\xF8</code> (248) a good choice, if it must be something user cannot enter with a keyboard !
  Any help &amp; advice would be welcome.</p>