title: Sell me on const correctness
body: <p>So why exactly is it that it's always recommended to use const as often as possible?  It seems to me that using const can be more of a pain than a help in C++.  But then again, I'm coming at this from the python perspective:  if you don't want something to be changed, don't change it.  So with that said, here are a few questions:</p>
  
  <ol>
  <li><p>It seems like every time I mark something as const, I get an error and have to change some other function somewhere to be const too.  Then this causes me to have to change <em>another</em> function somewhere else.  Is this something that just gets easier with experience?</p></li>
  <li><p>Are the benefits of using const <em>really</em> enough to compensate for the trouble?  If you don't intend on changing an object, why not just not write code that doesn't change it?</p></li>
  </ol>
  
  <p>I should note that at this point in time, I'm most focused on the benefits of using const for correctness and maintainability purposes, although it is also nice to have an idea of the performance implications.</p>