gistfile1.aw

<?php
class HogeController extend ParentController {
  public function fuga() {
    $filtered =SomeUtil::do_something($_GET["foo"]);
    RefactoredUtil::refactored_func($filtered);
  }
}

class RefactoredUtil {
  public static function refactored_func($ary) {
    $ary = array_filter($ary, function($a){
      if ($a==="") {
        return FALSE;
      } else {
        return TRUE;
      }
    });
    $this->do_somethins($ary);
    // Error occored!!
    // Becase, $ary["piyo"] equal NULL !!
    
  }
}