title: logical operator not working in php
body: <p>I have a php function that returns true or false and works fine when I say:</p>
  
  <pre><code>if (is_valid_locale($locale)) {
  // do something
  }
  </code></pre>
  
  <p>Yet, when I am trying to find something that does not return a valid locale with this:</p>
  
  <pre><code>if (!is_valid_locale($locale)) {
  // do something else
  }
  </code></pre>
  
  <p>When I echo out the function, it does spit out "f" for false. So the function works.</p>
  
  <p>I tried other things such as:</p>
  
  <pre><code>if (is_valid_locale($locale)==false) {
  // do something else
  }
  </code></pre>
  
  <p>However it still did not catch.</p>
  
  <p>Am I doing something wrong?</p>