title: Sorting and removing duplicate words in a line
body: <p>The <code>sort</code> command lets me put lines in alphabetical order and remove duplicate lines. I need something similar that can sort the words on a single line, put them in order, and remove any duplicates. Is there a command for this?</p>
  
  <p>E.g.:</p>
  
  <pre><code>zebra ant spider spider ant zebra ant
  </code></pre>
  
  <p>Changes to:</p>
  
  <pre><code>ant spider zebra
  </code></pre>
  
  <p>There is no space before the first word or after the last word.</p>