en_USSymbols top-level property Null safety

Implementation

var en_USSymbols = DateSymbols(
    NAME: 'en_US',
    ERAS: const ['BC', 'AD'],
    ERANAMES: const ['Before Christ', 'Anno Domini'],
    NARROWMONTHS: const [
      'J',
      'F',
      'M',
      'A',
      'M',
      'J',
      'J',
      'A',
      'S',
      'O',
      'N',
      'D'
    ],
    STANDALONENARROWMONTHS: const [
      'J',
      'F',
      'M',
      'A',
      'M',
      'J',
      'J',
      'A',
      'S',
      'O',
      'N',
      'D'
    ],
    MONTHS: const [
      'January',
      'February',
      'March',
      'April',
      'May',
      'June',
      'July',
      'August',
      'September',
      'October',
      'November',
      'December'
    ],
    STANDALONEMONTHS: const [
      'January',
      'February',
      'March',
      'April',
      'May',
      'June',
      'July',
      'August',
      'September',
      'October',
      'November',
      'December'
    ],
    SHORTMONTHS: const [
      'Jan',
      'Feb',
      'Mar',
      'Apr',
      'May',
      'Jun',
      'Jul',
      'Aug',
      'Sep',
      'Oct',
      'Nov',
      'Dec'
    ],
    STANDALONESHORTMONTHS: const [
      'Jan',
      'Feb',
      'Mar',
      'Apr',
      'May',
      'Jun',
      'Jul',
      'Aug',
      'Sep',
      'Oct',
      'Nov',
      'Dec'
    ],
    WEEKDAYS: const [
      'Sunday',
      'Monday',
      'Tuesday',
      'Wednesday',
      'Thursday',
      'Friday',
      'Saturday'
    ],
    STANDALONEWEEKDAYS: const [
      'Sunday',
      'Monday',
      'Tuesday',
      'Wednesday',
      'Thursday',
      'Friday',
      'Saturday'
    ],
    SHORTWEEKDAYS: const ['Sun', 'Mon', 'Tue', 'Wed', 'Thu', 'Fri', 'Sat'],
    STANDALONESHORTWEEKDAYS: const [
      'Sun',
      'Mon',
      'Tue',
      'Wed',
      'Thu',
      'Fri',
      'Sat'
    ],
    NARROWWEEKDAYS: const ['S', 'M', 'T', 'W', 'T', 'F', 'S'],
    STANDALONENARROWWEEKDAYS: const ['S', 'M', 'T', 'W', 'T', 'F', 'S'],
    SHORTQUARTERS: const ['Q1', 'Q2', 'Q3', 'Q4'],
    QUARTERS: const [
      '1st quarter',
      '2nd quarter',
      '3rd quarter',
      '4th quarter'
    ],
    AMPMS: const ['AM', 'PM'],
    DATEFORMATS: const ['EEEE, MMMM d, y', 'MMMM d, y', 'MMM d, y', 'M/d/yy'],
    TIMEFORMATS: const ['h:mm:ss a zzzz', 'h:mm:ss a z', 'h:mm:ss a', 'h:mm a'],
    FIRSTDAYOFWEEK: 6,
    WEEKENDRANGE: const [5, 6],
    FIRSTWEEKCUTOFFDAY: 5,
    DATETIMEFORMATS: const [
      '{1} \'at\' {0}',
      '{1} \'at\' {0}',
      '{1}, {0}',
      '{1}, {0}'
    ]);