public function normalizeVariableName($var_name)
    {
        if (substr($var_name, 0, 8) == '$GLOBALS') {
            // Replaces:
            // $GLOBALS['test']  => $test
            // $GLOBALS [ 'test' ] => $test
            $reg = <<<'EOS'
/^\$GLOBALS\s*\[\s*'([^']+)'\s*\]/
EOS;
            $var_name = preg_replace($reg, '$\1', $var_name);
        }
        return $var_name;
    }