Defines the format that date and time should be stored in. File core/modules/datetime/

public DateFormatInterface::getPattern()

public FormattedDateDiff::getMaxAge()

public static DateTimePlus::prepareArray($array, $force_valid_date = FALSE)

protected DateTimePlus::prepareFormat($format)

protected DateTimePlus::prepareTime($time)

The prepared timezone object used to construct this date. File core/lib/Drupal/Component/Datetime/DateTimePlus

public static DateHelper::dayOfWeek($date = NULL)

public DateFormatter::formatDiff($from, $to, $options = array())

protected DateFormatter::country() Returns