title: Reset R instance
body: <p>Is it possible to reset an instance of R?</p>
  
  <p>Eg. if I have used the commands</p>
  
  <pre><code>x &lt;- 1:10
  plot(x, -x)
  </code></pre>
  
  <p>And thus polluted the system with the x variable. In this state can I then revert back to a clean state without shutting R down and launching it again?</p>