title: How to tell if debug mode is on in CakePHP 3.x
body: <p>I want to know how I can retrieve the var inside of the env() function...</p>
  
  <pre><code>/**
   * Debug Level:
   *
   * Production Mode:
   * false: No error messages, errors, or warnings shown.
   *
   * Development Mode:
   * true: Errors and warnings shown.
   */
  'debug' =&gt; filter_var(env('DEBUG', true), FILTER_VALIDATE_BOOLEAN),
  </code></pre>
  
  <p>Right now I am using </p>
  
  <pre><code>&lt;?php if(DEBUG == true) { ?&gt;
  </code></pre>
  
  <p>but that is throwing an error</p>
  
  <pre><code>Use of undefined constant DEBUG - assumed 'DEBUG' (this will throw an Error in a future version of PHP)
  </code></pre>