title: #define negative numbers?
body: <p>Simple question, but I cannot seem to find the answer. Is it okay to use <code>#define</code> to define a negative number, as in:</p>
  
  <pre><code>#define kGravity -9.8
  </code></pre>
  
  <p>XCode is changing the 9.8 to the color of my numbers I have set (purple), but the <code>-</code> is being shown as the same color as the define statement (orange).</p>
  
  <p>Is this legal? Will it compile?</p>