title: R. How to use T and F instead of TRUE and FALSE
body: <p>R users can use T and F instead of TRUE and FALSE when they want to write logical values, but R output is always the long version, TRUE and FALSE.   </p>
  
  <p>Is there any way to force R to use T and F instead?<br>
  I mean use it in all outputs, including when you save an object to a file?   </p>
  
  <p>It's much neater and it takes less space on screen and in files.  </p>
  
  <p>I know I could replace all TRUEs for "T", and all FALSEs for "F" but this wouldn't be good because it won't be recognized as logical anymore, it would be text instead.   </p>
  
  <p>I think T and F aren't allowed in cran packages, but this is another story.</p>