code: private function parseNegatedRange($string)
      {
          $isNegated = strpos($string, static::NEGATION_CHAR) === 0;
          return [$isNegated, $isNegated ? substr($string, strlen(static::NEGATION_CHAR)) : $string];
      }
docs: Parses IP address/range for the negation with [[NEGATION_CHAR]].
  
  @param $string
  @return array `[0 => bool, 1 => string]`
  - boolean: whether the string is negated
  - string: the string without negation (when the negation were present)