title: Is 0 a decimal literal or an octal literal?
body: <p>Zero is always zero, so it doesn't matter. But in a recent discussion with a friend he said that octal literals are almost unused today.<sup>†</sup> Then it dawned upon me that actually almost <em>all</em> integer literals in my code <em>are</em> octal, namely <code>0</code>.</p>
  
  <p>Is <code>0</code> an octal literal according to the C++ grammar? What does the standard say?</p>
  
  <p><sub><sup>†</sup> The only real use I'm aware of is for unix file permissions.</sub></p>