title: Remove space between cat()
body: <p>Here's a simple one:</p>
  
  <pre><code>a &lt;- "a"
  cat(a,"b")
  
  
  "a b"
  </code></pre>
  
  <p>Why is there a whitespace between them?
  How to remove it so it come out like this:</p>
  
  <pre><code>"ab"
  </code></pre>