defaultImpl = function (_choice, _choicesLength) {
      _choice = Math.abs(_choice);

      if (_choicesLength === 2) {
        return _choice
          ? _choice > 1
            ? 1
            : 0
          : 1
      }

      return _choice ? Math.min(_choice, 2) : 0
    }
@param choice {number} a choice index given by the input to $tc: `$tc('path.to.rule', choiceIndex)`
@param choicesLength {number} an overall amount of available choices
@returns a final choice index