Proposed Update UAX #9, Unicode Bidirectional Algorithm

A new proposed update of UAX #9, Unicode Bidirectional Algorithm for the Unicode 9.0 release is now available for public review and comment.

The table in Section 2.7, Markup and Formatting, has been updated to reflect changes to isolates in HTML5 and CSS.

For further information and instructions on how to leave feedback, please see Public Review Issue #315.

PRI #279: Proposed Update UAX #9, Unicode Bidirectional Algorithm

The proposed update for Unicode 8.0 addresses three issues where the bidirectional algorithm, as written, did not produce the intended results in certain specific cases. Details and justification for the proposed changes to the specification are in a background document accessible from the PRI page.

The closing date for this issue is October 20, 2014. For information about how to discuss this issue and how to supply formal feedback, please see the feedback and discussion instructions on the PRI page.

The Public Review Issues index page is: http://www.unicode.org/review/

Testing the Unicode Bidirectional Algorithm for Unicode 6.3

Unicode Standard Annex #9, Unicode Bidirectional Algorithm (UBA), has a major update slated for release in September, 2013. This update is the most significant change in Unicode 6.3. The changes to the algorithm and text have been already been approved by the Unicode Technical Committee, subject to final editorial review.

The Unicode Technical Committee is encouraging implementations to test their code against the new test files and the two reference implementations during the month of July, 2013. It is vital that the interpretation of the text of the specification in UAX #9 be absolutely clear, and that the values in the test data be thoroughly tested by at least two implementations before release, because any changes after release—even to fix problems—can cause significant interoperability problems. The UBA is used for displaying all Arabic and Hebrew text on the web and in application programs, so there are significant ramifications for any changes to the algorithm.

The proposed update to UAX #9 involves a substantial extension of the UBA to allow for the implementation of isolate runs, introducing new Bidi_Class property values and formatting characters in support of that extension. There are also changes to Section 3.3.5, Resolving Neutral and Isolate Formatting Types to resolve paired punctuation marks as a unit. For details, see http://www.unicode.org/reports/tr9/tr9-28.html.

For further information about the review see http://www.unicode.org/review/pri254/.

Unicode 6.3 Beta Review

The Unicode® Consortium today announced the start of beta review for the forthcoming Unicode 6.3.0. All beta feedback must be submitted by April 29, 2013.

The main feature of Unicode 6.3 is the update of the Unicode Bidirectional Algorithm and five newly-encoded bidirectional format control characters: U+061C ARABIC LETTER MARK and the isolate span controls U+2066..U+2069. This version also rolls in various minor corrections for errata and other small updates for the Unicode Character Database.

Unicode is the foundation for all modern software and communications around the world, including all modern operating systems, browsers, and smart phones; modern web protocols (HTML, XML,...); and internationalized domain names. Thus it is important to ensure a smooth transition to each new version of the Unicode Standard. Software developers and other experts are strongly encouraged to review the beta data files and documentation for Unicode 6.3.0 carefully, and to provide any feedback regarding errors or other issues to the Unicode Consortium. Software developers can also get an early start in testing their programs with the beta data files so they will be ready for the release of Unicode 6.3.0 in June, 2013.

• See http://www.unicode.org/versions/beta-6.3.0.html, for information about testing the 6.3.0 beta.
• See http://www.unicode.org/versions/Unicode6.3.0/ for the current draft summary of Unicode 6.3.0.