title: in VBA/QTP how does string comparison work? Is there an efficient string hashing function built in?
body: <p>I need to compare two very large strings in QTP (intepreted by a vba-derived engine, I believe). I know these strings will exceed 100,000 characters, and I need to be able to detect when there is a change in one of these large strings. To start off I used the following:</p>
  
  <p>if prevtext &lt;> currenttext then
  ...
  end if</p>
  
  <p>I was expecting this to explode, but actually the script ran quite fast. There was no noticeable slowdown during the string comparison. So, I am suspicious that the string compare is actually truncating the strings outside of my scope or doing something else that would be cheating. Does anyone know if I can actually rely on the built in string comparison operator to compare two 100,000+ character strings? If not is there some native hashing function that I can replace this with? It just needs to be able to detect changes, not the content of the changes, and it needs to run quickly.</p>