KDE Core/Platform 11/Locale

Locale

• http://community.kde.org/KDE_Core/KLocale
• http://community.kde.org/KDE_Core/ISO_Codes
• http://community.kde.org/KDE_Core/QtMerge/QDateTime

KLocale

• Based on POSIX standard locales with many extensions.
• Have own locale settings files

What's wrong with KLocale:

• Gtk/Qt apps running under kde-workspace don't use the KDE locale
• KDE apps running under other platforms/workspaces do not use host locale
• Class merges settings, formatters, parsers and translations in one giant blob
• Circular dependencies with KConfig and KCalendarSystem
• Unnecessary dependency for Qt-Addon libraries

What's great about KLocale:

• Users can customise workspace locale settings
• Apps can customise locale settings
• Many advanced settings and formats not in QLocale (yet)

QLocale

• Based on Unicode CLDR standard locales.
• Obtaining a POSIX backend foruse on MeeGo in Qt4.8?
• http://www.unicode.org/reports/tr35/tr35-15.html
• Encodes CLDR data in .h file for performance

What's wrong with QLocale:

• Not all KDE, CLDR or POSIX settings are supported
• Users unable to change settings
• Apps unable to change individual settings without sub-classing QSystemLocale (to/from string methods partially mitigate need for this)

What's good with QLocale:

• Uses host settings on all platforms
• Low-level common class so good for Qt Addons
• Some settings not yet in KDE
• QSystemLocale settings container that can be sub-classed

The Plan

• Add all KDE settings that are also in CLDR to QLocale
• Use QLocale to replace KLocale's role as settings container
  • Gives correct Windows, Mac, Gnome, Meego settings
• KDE Workspace to set locale envvar on login if KDE locale different to system locale
  • Gives correct locale Gtk/Qt apps
• KCM to load settings from QLocale, write out as both POSIX and CLDR format files only if user chooses different settings
  • locale envvar then set to absolute path to users POSIX file so all Gtk apps get right settings
  • QLocale loads CLDR(?) file so KDE/Qt apps get right settings
• Apps use parser/formatter classes/api's to alter settings for one-off calls rather than changing the locale itself, or create a whole new locale object.
• Settings not available in QLocale are used by formatter/parser classes
• Remove our kde-runtime/l10n locale files
• Remove currency files and api to new Qt Addon ISO Codes library

Big Questions

• Breaks Source Compatibility in a big way, virtually every method and enum has a different name and parms as well as the different namespace. Keep KDE4support KLocale wrapped around QLocale?
• Date/Time formats: Keep POSIX formats (need own formatter/parser that translates Unicode format) or switch to Unicode format (not SC, QDateTime may not support all our features)
• How will QLocale load custom CLDR? Probably not via xml? Platform plugin? If not CLDR then fallback to custom POSIX file but lacks some settings.

What's missing in QLocale

• ISO codes for language/country, uses enums instead
• Digit Sets
• Binary Formats
• Page Size
• Decimal Places
• Separate monetary number symbols (decimal, sign, etc) but that's a Unicode CLDR thing
• Monetary formatting options internal only not exposed
• Digit grouping?
• Week number systems
• Calendar systems
• Duration
• Pretty format
• Day of Pray
• Working week start/end
• ...

What's extra in QLocale

• More locale metadata
• Script
• Quotes
• Lists
• More number symbols
• Standalone month/day names
• Read DateTime
• ...