function(
    dateTimePattern, fallbackPattern, dateTimeSymbols) {
  /**
   * Date time pattern used to format the dates.
   * @private {string}
   */
  this.dateTimePattern_ = dateTimePattern;

  /**
   * Date time formatter used to format the dates.
   * @private {!DateTimeFormat}
   */
  this.dateTimeFormatter_ =
      new DateTimeFormat(dateTimePattern, dateTimeSymbols);

  /**
   * Fallback interval pattern.
   * @private {string}
   */
  this.fallbackPattern_ = fallbackPattern;
}
function(
    dateTimePattern, fallbackPattern, dateTimeSymbols) {
  /**
   * Date time pattern used to format the dates.
   * @private {string}
   */
  this.dateTimePattern_ = dateTimePattern;

  /**
   * Date time formatter used to format the dates.
   * @private {!DateTimeFormat}
   */
  this.dateTimeFormatter_ =
      new DateTimeFormat(dateTimePattern, dateTimeSymbols);

  /**
   * Fallback interval pattern.
   * @private {string}
   */
  this.fallbackPattern_ = fallbackPattern;
}
function ( dateTimePattern , fallbackPattern , dateTimeSymbols ) { /**
   * Date time pattern used to format the dates.
   * @private {string}
   */ this . dateTimePattern_ = dateTimePattern ; /**
   * Date time formatter used to format the dates.
   * @private {!DateTimeFormat}
   */ this . dateTimeFormatter_ = new DateTimeFormat ( dateTimePattern , dateTimeSymbols ) ; /**
   * Fallback interval pattern.
   * @private {string}
   */ this . fallbackPattern_ = fallbackPattern ; }
Constructs a DateTimeFormatter_ object which implements the Formatter_
interface.

Internal object to construct and store a goog.i18n.DateTimeFormat for the
a datetime pattern and formats dates using the fallback interval pattern
(e.g. '{0} – {1}').

@param {string} dateTimePattern Datetime pattern used to format the dates.
@param {string} fallbackPattern Fallback interval pattern to be used with the
datetime pattern.
@param {!DateTimeSymbolsType} dateTimeSymbols Symbols to use with
the datetime format.
@constructor
@implements {Formatter_}
@private
Constructs a DateTimeFormatter_ object which implements the Formatter_ interface .
A date time interval pattern.