title: Use "define" from another PHP file
body: <p>I have file a.php with:</p>
  
  <pre><code>define('COLOR','blue');
  </code></pre>
  
  <p>and file b.php with:</p>
  
  <pre><code>include('/a.php');
  echo COLOR;
  </code></pre>
  
  <p>... and "COLOR" is echoed. Is there something I need to do to carry the definition over?</p>
  
  <p>File B is a WordPress functions file,  which is possibly the cause - but I want to check first that the PHP is correct, having never used define() before... Thanks.</p>