title: R: how to clear all warnings
body: <p>I would like to clear the warnings() list using a command line.</p>
  
  <p>I have tried with no success</p>
  
  <pre><code>&gt; rm(last.warning, envir = baseenv())  
  Error in rm(last.warning, envir = baseenv()) :   
  cannot remove variables from the base environment
  </code></pre>
  
  <p>any idea?</p>