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== Full CLDR Date Format and Calendar System support ==
== Full CLDR Date Format and Calendar System support ==


The CLDR Date Format support and Calendar System support are closely connected and need to be designed together, although they will be separately implemented.
The CLDR Date Format support and Calendar System support are closely connected and need to be designed together, although they will be separately implemented.  The following API design is based on the CLDR standard.


The following API design is based on the CLDR standard,and is not Source Compatible with Qt4. The Qt4 API is inconsistent, incomplete, and requires modification to fully support CLDR, so the opportunity should be taken to fully overhaul the API.  Most apps will be unaffected as they should simply be using the default toString()/fromString() methods.
Backwards source compatibility is required to be maintained by the QDate class using the QT4_COMPAT directive.
 
The Qt4 API is inconsistent, incomplete, and requires modification to fully support CLDR, so the opportunity should be taken to fully overhaul the API.  Most apps will be unaffected as they should simply be using the default toString()/fromString() methods.


=== Object Model ===
=== Object Model ===
Line 13: Line 15:
The physical object model is still uncertain.  The logical model is as follows:
The physical object model is still uncertain.  The logical model is as follows:


QLocale - The locale container, provides type of calendar system, date/time formats, and date/time name translations for a given locale which will be used by the QDateTime for formatting.  Existing class to be modified.
QLocale - The locale class, container for type of calendar system, date/time formats, and date/time name translations, and accessor methods to format/parse date/times in that locale.  Existing class to be modified.
 
QCalendarSystem - A private virtual base class implementing Calendar System calculations.  Derived implementations like QCalendarSystemGregorian will also be private.  It is not intended to expose this class to public access.  New class.
 
QDateTimeParser - Takes a QString, date/time format, QCalendarSystem, and QLocale and returns a QDateTime.  Existing private class to be modified.
 
QDateTimeFormatter - Takes a QDateTime and date/time format and returns a QString.  New private class.


QDate - Holds a date as a Julian Day number, a QCalendarSystem calculator instance for converting the JD to/from YMD, and an optional QLocale for use converting the JD to/from YMD and string formats.  Existing class to be modified.
QDate - A container class to hold a Julian Day number.  Shouldn't have any ymd or string methods, but to maintain full backwards compatibility will use QT4_COMPAT for all existing ymd and string methods.


Note that by default the system QLocale and QCalendarSystem will be used by a default created QDate, but these can both be over-ridden using QDate::setLocale() and/or QDate::setCalendarSystem().
QDateCalculator.  A calculator class for converting a QDate to/from YMD values. No virtuals to be used.


More radically, the QDatePrivate and QCalendarSystem could be merged with for example QDateGregorianPrivate or QDateJulianPrivate instances being created depending on the system locale.  This could be more memory efficient and shared better.  A variation is for QDate itself to be sub-classed (QDateGregorian, QDateHebrew, etc) which would allow for apps to derive their own calendars.
QDateTimeParser - Takes an input string, date/time format, and locale and returns a QDateTime.  Existing private class to be modified.


Alternative:  If the above doesn't work too well then use a variant on the current KDE model.  The QCalendarSystem object is embedded in the QLocale, with the QLocale embedded in the QDate.  The problems here is that this will probably force QCalendarSystem to be public, and becomes a problem with setCalendar() needing to be on QLocale which breaks QLocales design.
QDateTimeFormatter - Takes a QDateTime, date/time format and locale and returns a QString.  New private class based on the QLocale formatter.  The QDateTime formatter is to be deleted..


=== Implementation Plan ===
=== Implementation Plan ===
Line 33: Line 29:
The following phased implementation is planned:
The following phased implementation is planned:


* Create new private QCalendarSystem base class, move current calendar code from QDate into QCalendarSystem, change QDate to embed QCalendarSystem and make calls to it.  All existing tests should still pass.
* Create new private QDateTimeFormatter class, move current formatting code from QLocale and QDateTime into QDateTimeFormatter, change QDateTime to make calls to it.  All existing tests should still pass.
* Create new private QDateTimeFormatter class, move current formatting code from QLocale and QDateTime into QDateTimeFormatter, change QDateTime to make calls to it.  All existing tests should still pass.
* Create new private QDateCalculator base class implementing many calendars.
* Change QDateTimeFormatter and QDateTimeParser to fix the currently supported field codes to be CLDR compliant.  Modify existing tests to ensure they still pass.
* Change QDateTimeFormatter and QDateTimeParser to fix the currently supported field codes to be CLDR compliant.  Modify existing tests to ensure they still pass.
* Implement new formatting api but making calls to existing backend code, for options that don't yet have the backend coded just translate to a sensible replacement, i.e. for FullDate return LongDate.  Only supported CalendarSystem is DefaultCalendar.  All existing tests should still pass.
* Implement new formatting api but making calls to existing backend code, for options that don't yet have the backend coded just translate to a sensible replacement, i.e. for FullDate return LongDate.  Only supported CalendarSystem is DefaultCalendar.  All existing tests should still pass.
Line 55: Line 51:
=== API Changes ===
=== API Changes ===


Replace the old Qt, QLocale and QDate enums:
Deprecate the old Qt and QDate enums:


<syntaxhighlight lang="cpp-qt">
<syntaxhighlight lang="cpp-qt">
Line 75: Line 71:
</syntaxhighlight>
</syntaxhighlight>


with new QLocale enums:
Delete or Deprecate the old QLocale enums:
 
<syntaxhighlight lang="cpp-qt">
  // Merges both format type and field type!
  enum QLocale::FormatType { LongFormat, ShortFormat, NarrowFormat };
</syntaxhighlight>
 
Add new QLocale enums:


<syntaxhighlight lang="cpp-qt">
<syntaxhighlight lang="cpp-qt">
Line 96: Line 99:


   // CLDR calendar attribute
   // CLDR calendar attribute
   enum QLocale::CalendarSystem { DefaultCalendar = -1,  // i.e. locale default
   enum QLocale::CalendarSystem { DefaultCalendar = 0,  // i.e. locale default
                                 GregorianCalendar = 0,
                                 GregorianCalendar = 1,
                                JulianCalendar = 2,
                                 ... };
                                 ... };


   // CLDR year type attribute
   // CLDR year type attribute, in Qt or QDateTime namespace instead?
  // Would prefer in QDateTime namespace, but needed for QLocale::monthName()
   enum QLocale::YearType { StandardYear, LeapYear }
   enum QLocale::YearType { StandardYear, LeapYear }


  // CLDR date time fields, maybe in Qt or QLocale namespace?
  enum QDateTime::DateTimeField { Year, Month, Day, Hour, Minute, Second, ... }
  // Common standard formats, maybe in Qt or QLocale namespace?
   enum QDateTime::DateTimeFormat { IsoFormat,
   enum QDateTime::DateTimeFormat { IsoFormat,
                                   RfcFormat,
                                   RfcFormat,
Line 111: Line 118:
</syntaxhighlight>
</syntaxhighlight>


Alternative: Put in Qt:: NameSpace.


Replace the old QLocale and QDate name methods:
Add new QLocale calendar sytem methods:
 
<syntaxhighlight lang="cpp-qt">
  CalendarSystem QLocale::calendarSystem(); const            // current calendar, usually locale default
  QList<CalendarSystem> QLocale::calendarSystems() const;    // locale preferred list
  QList<CalendarSystem> QLocale::allCalendarSystems() const; // all calendars list
  QDateCalculator QLocale::calendar();                      // current calendar calculator
</syntaxhighlight>
 
Deprecate the old QDate name methods:
 
<syntaxhighlight lang="cpp-qt">
  static QString QDate::shortMonthName(int month, MonthNameType type = QDate::DateFormat);
  static QString QDate::shortDayName(int weekday, MonthNameType type = QDate::DateFormat);
  static QString QDate::longMonthName(int month, MonthNameType type = QDate::DateFormat);
  static QString QDate::longDayName(int weekday, MonthNameType type = QDate::DateFormat);
</syntaxhighlight>
 
Delete or Deprecate the old QLocale name methods:


<syntaxhighlight lang="cpp-qt">
<syntaxhighlight lang="cpp-qt">
Line 122: Line 146:
   QString QLocale::amText() const;
   QString QLocale::amText() const;
   QString QLocale::pmText() const;
   QString QLocale::pmText() const;
  static QString QDate::shortMonthName(int month, MonthNameType type = QDate::DateFormat);
  static QString QDate::shortDayName(int weekday, MonthNameType type = QDate::DateFormat);
  static QString QDate::longMonthName(int month, MonthNameType type = QDate::DateFormat);
  static QString QDate::longDayName(int weekday, MonthNameType type = QDate::DateFormat);
</syntaxhighlight>
</syntaxhighlight>


with new QLocale name methods:
Add new QLocale name methods:


<syntaxhighlight lang="cpp-qt">
<syntaxhighlight lang="cpp-qt">
Line 145: Line 164:
                                 FieldContext context = FormatContext,
                                 FieldContext context = FormatContext,
                                 CalendarSystem calendar = DefaultCalendar) const;
                                 CalendarSystem calendar = DefaultCalendar) const;
</syntaxhighlight>
and extend later with new feature name methods:
<syntaxhighlight lang="cpp-qt">
   QString QLocale::eraName(int year,
   QString QLocale::eraName(int year,
                           FieldFormat format = LongName,
                           FieldFormat format = LongName,
Line 162: Line 176:
                                 FieldContext context = FormatContext) const;
                                 FieldContext context = FormatContext) const;
</syntaxhighlight>
</syntaxhighlight>
Note the QDate methods are removed as being redundent, see also the QDate::setLocale() method below.  Alternatively they could remain in QDate but not as static's taking month/weekday number, but instead return the name for the QDate's value, however this is easily obtained anyway using toString().


Modify the QLocale date/time format methods:
Modify the QLocale date/time format methods:
Line 173: Line 185:
</syntaxhighlight>
</syntaxhighlight>


to use the new enums:
to replace FormatType with StringType:
 
<syntaxhighlight lang="cpp-qt">
  QString QLocale::dateFormat(StringFormat format = LongFormat) const;
  QString QLocale::timeFormat(StringFormat format = LongFormat) const;
  QString QLocale::dateTimeFormat(StringFormat format = LongFormat) const;
</syntaxhighlight>
 
Deprecate all the QDateTime toString() and fromString() methods:


<syntaxhighlight lang="cpp-qt">
<syntaxhighlight lang="cpp-qt">
   QString QLocale::dateFormat(StringFormat format = LongFormat);
   QString QDate::toString(Qt::DateFormat f = Qt::TextDate) const;
   QString QLocale::timeFormat(StringFormat format = LongFormat);
  QString QDate::toString(const QString &format) const;
   QString QLocale::dateTimeFormat(StringFormat format = LongFormat);
 
  static QDate QDate::fromString(const QString &s, Qt::DateFormat f = Qt::TextDate);
  static QDate QDate::fromString(const QString &s, const QString &format);
 
  QString QTime::toString(Qt::DateFormat f = Qt::TextDate) const;
   QString QTime::toString(const QString &format) const;
 
  static QTime QTime::fromString(const QString &s, Qt::DateFormat f = Qt::TextDate);
  static QTime QTime::fromString(const QString &s, const QString &format);
 
  QString QDateTime::toString(Qt::DateFormat f = Qt::TextDate) const;
   QString QDateTime::toString(const QString &format) const;
 
  static QDateTime QDateTime::fromString(const QString &s, Qt::DateFormat f = Qt::TextDate);
  static QDateTime QDateTime::fromString(const QString &s, const QString &format);
</syntaxhighlight>
</syntaxhighlight>


Remove all the QLocale toString(), toDate(), toTime(), toDateTime() methods, all formatting/parsing to be done in QDate/QTime/QDateTime.
Mondify the QLocale toString() and fromString() methods:
 
<syntaxhighlight lang="cpp-qt">
  QString QLocale::toString(const QDate &date, FormatType format = LongFormat) const;
  QString QLocale::toString(const QTime &time, FormatType format = LongFormat) const;
  QString QLocale::toString(const QDateTime &dateTime, FormatType format = LongFormat) const;
 
  QDate QLocale::toDate(const QString &string, FormatType = LongFormat) const;
  QTime QLocale::toTime(const QString &string, FormatType = LongFormat) const;
  QDateTime QLocale::toDateTime(const QString &string, FormatType format = LongFormat) const;
</syntaxhighlight>


Replace all the QDate toString() and fromString() methods with the following:
to replace FormatType with StringType:


<syntaxhighlight lang="cpp-qt">
<syntaxhighlight lang="cpp-qt">
   QString QDate::toString(const QString &format) const;
   QString QLocale::toString(const QDate &date, StringType format = LongFormat) const;
   QString QDate::toString(QLocale::StringFormat format = QLocale::LongFormat) const;
   QString QLocale::toString(const QTime &time, StringType format = LongFormat) const;
   QString QDate::toString(QDateTime::DateTimeFormat format) const;
   QString QLocale::toString(const QDateTime &dateTime, StringType format = LongFormat) const;


   static QDate QDate::fromString(const QString &string, const QString &format);
   QDate QLocale::toDate(const QString &string, StringType = LongFormat) const;
   static QDate QDate::fromString(const QString &string, QLocale::StringFormat format = QLocale::LongFormat);
   QTime QLocale::toTime(const QString &string, StringType = LongFormat) const;
   static QDate QDate::fromString(const QString &string, QDateTime::DateTimeFormat format);
   QDateTime QLocale::toDateTime(const QString &string, StringType format = LongFormat) const;
</syntaxhighlight>
</syntaxhighlight>


Repeat exactly the same for QTime and QDateTime.
Add the following new toString/fromSting methods to QLocale


Alternative: replace the method names toString() and fromString() with formatDate() and parseDate(), but this would break Source Compatibility for virtually every app.
<syntaxhighlight lang="cpp-qt">
  QString QLocale::toString(const QDate &date, QDateTime::DateTimeFormat format) const;
  QString QLocale::toString(const QTime &time, QDateTime::DateTimeFormat format) const;
  QString QLocale::toString(const QDateTime &dateTime, QDateTime::DateTimeFormat format) const;
 
  QDate QLocale::toDate(const QString &string, QDateTime::DateTimeFormat format) const;
  QTime QLocale::toTime(const QString &string, QDateTime::DateTimeFormat format) const;
  QDateTime QLocale::toDateTime(const QString &string, QDateTime::DateTimeFormat format) const;
</syntaxhighlight>


Modify the existing string date field format codes to be CLDR compliant as follows:
Modify the existing string date field format codes to be CLDR compliant as follows:
Line 233: Line 285:
       W - Week of Month
       W - Week of Month
       F - Day of Week In Month
       F - Day of Week In Month
</syntaxhighlight>
Add the following new methods to support calendar systems and related features:
<syntaxhighlight lang="cpp-qt">
  CalendarSystem QLocale::calendarSystem()            // locale default calendar
  QList<CalendarSystem> QLocale::calendarSystems()    // locale preferred list
  QList<CalendarSystem> QLocale::allCalendarSystems() // all calendars list
  void QDate::setCalendarSystem(KLocale::CalendarSystem calendar);
  QLocale::CalendarSystem QDate::calendarSystem();
  void QDate::setLocale(const QLocale & locale);
  QLocale QDate::locale();
  int QDate::eraYear()
  int QDate::monthsInYear()
  int QDate::weeksInYear()
  int QDate::daysInWeek()
</syntaxhighlight>
</syntaxhighlight>

Revision as of 19:55, 3 September 2011

The initial proposal for merging KDE features in Qt5 as presented at QtCS is documented on the QtCS wiki at http://developer.qt.nokia.com/groups/qt_contributors_summit/wiki/QDateTime

This page documents specific API proposals.

Full CLDR Date Format and Calendar System support

The CLDR Date Format support and Calendar System support are closely connected and need to be designed together, although they will be separately implemented. The following API design is based on the CLDR standard.

Backwards source compatibility is required to be maintained by the QDate class using the QT4_COMPAT directive.

The Qt4 API is inconsistent, incomplete, and requires modification to fully support CLDR, so the opportunity should be taken to fully overhaul the API. Most apps will be unaffected as they should simply be using the default toString()/fromString() methods.

Object Model

The physical object model is still uncertain. The logical model is as follows:

QLocale - The locale class, container for type of calendar system, date/time formats, and date/time name translations, and accessor methods to format/parse date/times in that locale. Existing class to be modified.

QDate - A container class to hold a Julian Day number. Shouldn't have any ymd or string methods, but to maintain full backwards compatibility will use QT4_COMPAT for all existing ymd and string methods.

QDateCalculator. A calculator class for converting a QDate to/from YMD values. No virtuals to be used.

QDateTimeParser - Takes an input string, date/time format, and locale and returns a QDateTime. Existing private class to be modified.

QDateTimeFormatter - Takes a QDateTime, date/time format and locale and returns a QString. New private class based on the QLocale formatter. The QDateTime formatter is to be deleted..

Implementation Plan

The following phased implementation is planned:

  • Create new private QDateTimeFormatter class, move current formatting code from QLocale and QDateTime into QDateTimeFormatter, change QDateTime to make calls to it. All existing tests should still pass.
  • Create new private QDateCalculator base class implementing many calendars.
  • Change QDateTimeFormatter and QDateTimeParser to fix the currently supported field codes to be CLDR compliant. Modify existing tests to ensure they still pass.
  • Implement new formatting api but making calls to existing backend code, for options that don't yet have the backend coded just translate to a sensible replacement, i.e. for FullDate return LongDate. Only supported CalendarSystem is DefaultCalendar. All existing tests should still pass.
  • Add to QDateTimeFormatter and QDateTimeParser the CLDR field codes that are already supported by existing QDate api. Write new tests.
  • Convert unit tests from old api to new api. All existing tests should still pass.
  • Convert widgets and other Qt code to new api. All existing tests should still pass.
  • Remove old api. All existing tests should still pass.
  • Modify QLocale CLDR backend to return full set of values for new api. Write new tests.
  • Modify QLocale Mac backend to return full set of values for new api. Write new tests.
  • Modify QLocale Windows backend to return full set of values for new api. Write new tests.
  • Add QDateTime setLocale() support
  • Add Era support
  • Add Quarters support
  • Add Ordinal Date support
  • Add Week Date support
  • Add Date Maths support
  • Add more Calendar Systems
  • Add QDate setCalendarSystem() support

API Changes

Deprecate the old Qt and QDate enums: 

  // Merges both format and field type!
  enum QLocale::FormatType { LongFormat, ShortFormat, NarrowFormat };

  // Used for both month and day names!
  enum QDate::MonthNameType { DateFormat = 0, StandaloneFormat };

  enum Qt::DateFormat { TextDate,                     // default Qt
                        ISODate,                      // ISO 8601
                        SystemLocaleDate,             // deprecated
                        LocalDate = SystemLocaleDate, // deprecated
                        LocaleDate,                   // deprecated
                        SystemLocaleShortDate,
                        SystemLocaleLongDate,
                        DefaultLocaleShortDate,
                        DefaultLocaleLongDate };

Delete or Deprecate the old QLocale enums: 

  // Merges both format type and field type!
  enum QLocale::FormatType { LongFormat, ShortFormat, NarrowFormat };

Add new QLocale enums: 

  // CLDR format length attribute for date/time/number/currency
  enum QLocale::StringFormat { FullFormat,
                               LongFormat,
                               MediumFormat,
                               ShortFormat };

  // CLDR field width attribute
  enum QLocale::FieldFormat { LongName,      // e.g. January
                              ShortName,     // e.g. Jan
                              NarrowName,    // e.g. J
                              LongNumber,    // e.g. 01
                              ShortNumber }; // e.g. 1

  // CLDR context attribute
  enum QLocale::FieldContext { FormatContext,        // Use in a format
                               StandaloneContext };  // Use standalone

  // CLDR calendar attribute
  enum QLocale::CalendarSystem { DefaultCalendar = 0,  // i.e. locale default
                                 GregorianCalendar = 1,
                                 JulianCalendar = 2,
                                 ... };

  // CLDR year type attribute, in Qt or QDateTime namespace instead?
  enum QLocale::YearType { StandardYear, LeapYear }

  // CLDR date time fields, maybe in Qt or QLocale namespace?
  enum QDateTime::DateTimeField { Year, Month, Day, Hour, Minute, Second, ... }

  // Common standard formats, maybe in Qt or QLocale namespace?
  enum QDateTime::DateTimeFormat { IsoFormat,
                                   RfcFormat,
                                   Rfc3339Format,	
                                   WeekFormat,
                                   OrdinalFormat };


Add new QLocale calendar sytem methods: 

  CalendarSystem QLocale::calendarSystem(); const            // current calendar, usually locale default
  QList<CalendarSystem> QLocale::calendarSystems() const;    // locale preferred list
  QList<CalendarSystem> QLocale::allCalendarSystems() const; // all calendars list
  QDateCalculator QLocale::calendar();                       // current calendar calculator

Deprecate the old QDate name methods: 

  static QString QDate::shortMonthName(int month, MonthNameType type = QDate::DateFormat);
  static QString QDate::shortDayName(int weekday, MonthNameType type = QDate::DateFormat);
  static QString QDate::longMonthName(int month, MonthNameType type = QDate::DateFormat);
  static QString QDate::longDayName(int weekday, MonthNameType type = QDate::DateFormat);

Delete or Deprecate the old QLocale name methods: 

  QString QLocale::monthName(int month, FormatType format = LongFormat) const;
  QString QLocale::standaloneMonthName(int month, FormatType format = LongFormat) const;
  QString QLocale::dayName(int weekday, FormatType format = LongFormat) const;
  QString QLocale::standaloneDayName(int weekday, FormatType format = LongFormat) const;
  QString QLocale::amText() const;
  QString QLocale::pmText() const;

Add new QLocale name methods: 

  QString QLocale::monthName(int month,
                             FieldFormat format = LongName,
                             FieldContext context = FormatContext,
                             YearType yearType = StandardYear,
                             CalendarSystem calendar = DefaultCalendar) const;
  QString QLocale::weekdayName(int weekday,
                               FieldFormat format = LongName,
                               FieldContext context = FormatContext,
                               CalendarSystem calendar = DefaultCalendar) const;
  QString QLocale::dayPeriodName(QTime time,
                                 FieldFormat format = LongName,
                                 FieldContext context = FormatContext,
                                 CalendarSystem calendar = DefaultCalendar) const;
  QString QLocale::eraName(int year,
                           FieldFormat format = LongName,
                           FieldContext context = FormatContext,
                           CalendarSystem calendar = DefaultCalendar) const;
  QString QLocale::quarterName(int quarter,
                               FieldFormat format = LongName,
                               FieldContext context = FormatContext,
                               CalendarSystem calendar = DefaultCalendar) const;
  QString QLocale::calendarName(CalendarSystem calendar = DefaultCalendar,
                                FieldFormat format = LongName,
                                FieldContext context = FormatContext) const;

Modify the QLocale date/time format methods: 

    QString QLocale::dateFormat(FormatType format = LongFormat) const;
    QString QLocale::timeFormat(FormatType format = LongFormat) const;
    QString QLocale::dateTimeFormat(FormatType format = LongFormat) const;

to replace FormatType with StringType: 

  QString QLocale::dateFormat(StringFormat format = LongFormat) const;
  QString QLocale::timeFormat(StringFormat format = LongFormat) const;
  QString QLocale::dateTimeFormat(StringFormat format = LongFormat) const;

Deprecate all the QDateTime toString() and fromString() methods: 

  QString QDate::toString(Qt::DateFormat f = Qt::TextDate) const;
  QString QDate::toString(const QString &format) const;

  static QDate QDate::fromString(const QString &s, Qt::DateFormat f = Qt::TextDate);
  static QDate QDate::fromString(const QString &s, const QString &format);

  QString QTime::toString(Qt::DateFormat f = Qt::TextDate) const;
  QString QTime::toString(const QString &format) const;

  static QTime QTime::fromString(const QString &s, Qt::DateFormat f = Qt::TextDate);
  static QTime QTime::fromString(const QString &s, const QString &format);

  QString QDateTime::toString(Qt::DateFormat f = Qt::TextDate) const;
  QString QDateTime::toString(const QString &format) const;

  static QDateTime QDateTime::fromString(const QString &s, Qt::DateFormat f = Qt::TextDate);
  static QDateTime QDateTime::fromString(const QString &s, const QString &format);

Mondify the QLocale toString() and fromString() methods: 

  QString QLocale::toString(const QDate &date, FormatType format = LongFormat) const;
  QString QLocale::toString(const QTime &time, FormatType format = LongFormat) const;
  QString QLocale::toString(const QDateTime &dateTime, FormatType format = LongFormat) const;

  QDate QLocale::toDate(const QString &string, FormatType = LongFormat) const;
  QTime QLocale::toTime(const QString &string, FormatType = LongFormat) const;
  QDateTime QLocale::toDateTime(const QString &string, FormatType format = LongFormat) const;

to replace FormatType with StringType: 

  QString QLocale::toString(const QDate &date, StringType format = LongFormat) const;
  QString QLocale::toString(const QTime &time, StringType format = LongFormat) const;
  QString QLocale::toString(const QDateTime &dateTime, StringType format = LongFormat) const;

  QDate QLocale::toDate(const QString &string, StringType = LongFormat) const;
  QTime QLocale::toTime(const QString &string, StringType = LongFormat) const;
  QDateTime QLocale::toDateTime(const QString &string, StringType format = LongFormat) const;

Add the following new toString/fromSting methods to QLocale 

  QString QLocale::toString(const QDate &date, QDateTime::DateTimeFormat format) const;
  QString QLocale::toString(const QTime &time, QDateTime::DateTimeFormat format) const;
  QString QLocale::toString(const QDateTime &dateTime, QDateTime::DateTimeFormat format) const;

  QDate QLocale::toDate(const QString &string, QDateTime::DateTimeFormat format) const;
  QTime QLocale::toTime(const QString &string, QDateTime::DateTimeFormat format) const;
  QDateTime QLocale::toDateTime(const QString &string, QDateTime::DateTimeFormat format) const;

Modify the existing string date field format codes to be CLDR compliant as follows: 

   ddd - Weekday - Change to EEE
  dddd - Weekday - Change to EEEE
    AP - AM/PM - Remove, already have A
    ap - am/pm - Remove, already have a
     h - Hour - Modify behaviour to match CLDR
    hh - Hour - Modify behaviour to match CLDR
     t - Timezone - Change to z

Add new CLDR date field format codes for existing or new api: 

  ddddd - Weekday narrow name
  MMMMM - Month narrow name
      y - Year without leading zeros
      d - Day of Year
      w - Week of Year
      Y - Week Year
      L - Stand-alone Month
      e - Weekday
      E - Weekday 
      c - Stand-alone Weekday
      G - Era name
      z - Timezone
      Z - Timezone
      v - Timezone
      V - Timezone
      Q - Quarter of Year
      q - Stand-alone Quarter of Year
      W - Week of Month
      F - Day of Week In Month
Retrieved from "https://community.kde.org/index.php?title=KDE_Core/QtMerge/QDateTime&oldid=14710"