Proposed Unicode Technical Standard #35

Unicode Common Locale Data & Rules (CLDR)
Appendix A: Modifications

Summary

The CLDR specification is presented in multiple Parts, each on its own web page. This Part covers the changes to the CLDR specification since the previous release.

For the full header and a general introduction, see Unicode Common Locale Data & Rules (CLDR): Part 1.

Contents of Appendix A, Modifications

• Modifications
  • Changes in CLDR Version 49 (Differences from Version 48.0)
  • General
  • Locales
    • Date and Time
    • MessageFormat
  • Numbers
  • Units
  • Collation
  • Keyboard
  • Segmentation

Modifications

Changes in CLDR Version 49 (Differences from Version 48.0)

General

• Replaced “Common Locale Data Repository (CLDR)” by “Unicode Common Locale Data & Rules (CLDR)” and the title of the specification “UTS #35: Unicode Locale Data Markup Language (LDML)” by “UTS #35: Unicode Common Locale Data & Rules (CLDR)”.
  • The former names and the acronym “LDML” led to many misunderstandings and have been changed for clarity.
  • Note that all references under the former names and the LDML acronym remain valid; such references on the Unicode site will be updated over time.

Locales

• typeValues Added typeValues for On/Off translations in menus and locale display names

• Key/Type Descriptions In the Key/Type Description table, added a description of which keys/types use constructed values, and a brief description of the typeValue element.
  • These elements are not present in root.xml. When not present in a top-level locale, they fall back to the key or value identifier.
  • Also changed the table from HTML into Markdown, with each Key description (such as co for collation) having its own level-five section heading.
• Boundary Spacing Added new description of placeholderBoundarySpacing.
• (48.2) New section Nested Bracket Replacement.
• (48.2) Locale Display Name Algorithm updated to use the nested bracket replacement data and avoid nested parentheses by flattening -t- (transform) language names.
  • As part of this, the display name order is changed so that any names for -u- items appear before (instead of after) any names for -t- items.
• (48.2) Specified that missing <keys> translations should fall back to the key identifier.
• (48.2) The section "Enhanced Language Matching" was retitled to Language Matching Variables and clarified.

Date and Time

• Calendar era codes Added length limit and clarified format.

• Date Field Symbols & Skeletons Document that pattern-only symbols (L, q, c), non-canonical hour symbols (K, k), and invalid day period combinations are discouraged in skeletons and planned for deprecation in CLDR 50.

• Missing Skeleton Fields Added Date-Timezone pattern for gluing date and time zone fields together, evaluated before Time-Day-Of-Week, and clarified placeholder assignments and usage in appendItems.

• interval formats Described the new interval range separator patterns and how they are used to produce fallback patterns.
• Numeric date/time separators Added separators for times and numeric dates in technical preview to allow easier customization.

• Ordinal days, ddd symbol Added documentation of dayOfMonth elements and the related ddd symbol in technical preview.

• Hour Cycle Pattern Variations Specified how semantic skeleton hour cycle options (Clock12, Clock24, H11, H12, H23, H24) adjust the matched pattern after standard skeleton matching.

• Time Zone Names Removed gmtZeroOffset item.
• Time_Zone_Format_Terminology Clarified that not all timezones have location (or location format).
• Time_Zone_Goals Modified the location format construction.
• Time Zone Format Terminology Clarified the computation of the exemplar city for non-location zones.

MessageFormat

• :currency, :percent The :currency and :percent functions are now Stable, with the same implementations as previously.
• The u:locale option (previously in Draft) has been dropped from the specification.

Numbers

• Currencies Revised the numberFormat description for currencies.

• Number Symbols Added a subsection heading for each number symbol.
• Currency Formats, Currencies, Supplemental Currency Data Added subsection headings for currency formatting rules, pattern variants (alt="alphaNextToNumber", alt="noCurrency", currencyPatternAppendISO), currency placeholders (¤..¤¤¤¤¤), unitPattern display name formatting, currencySpacing, and supplemental currency fractions and region mappings.

• Plural rules syntax Made it clear that plural rules are evaluated in semantic order (zero, then one,…).

• Number Formats, Miscellaneous Patterns, Formatting Added a subsection heading for each number format type (decimalFormats, percentFormats, scientificFormats), each miscellaneous pattern (approximately, atMost, atLeast, range), and special values.

Units

• Unit Preferences Data Made formatting and phrasing more internally consistent

Collation

Part 5: Collation has been updated to reflect the changes that were upstreamed into UTS #10 as part of Unicode 18.0:

• The UCA DUCET now also includes the ten Tibetan contractions that had been added earlier in CLDR.
• As a result, the order of all characters in the CLDR root collation is now the same as in the UCA DUCET. (There is still a difference in the default sets of “variable” characters, and CLDR defines a tailoring mechanism and additional features.)
• The UCA now has the same mappings and behavior for U+FFFE and U+FFFF which had been defined earlier in CLDR.

Keyboard

• References and links into the section concerning keyboard test data (which was removed prior to spec finalization) were removed.
• Default Backspace Transform Normalization for the default backspace transform was clarified, and authors were encouraged to add backspace transforms to avoid the default.

Segmentation

• (48.1) Segmentations removed outdated note about X Format*->X.

Note that small changes such as typos and link fixes are not listed above. Modifications in previous versions are listed in those respective versions. Click on Previous Version in the header until you get to the desired version.

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