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Author: Richard Ishida
Bidirectional text support
Markup should be available to support the needs of bidirectional scripts.
Generally the Unicode bidirectional algorithm will cause text in scripts such as Arabic and Hebrew to appropriately order mixed script text. Sometimes, however, additional help is needed. For example, in the following phrase the 'W3C' and the comma should appear to the left side of the quotation. This cannot be achieved using the bidirectional algorithm alone.
The title says "פעילות הבינאום, W3C" in Hebrew.
The desired effect can be achieved using Unicode control characters, but this is not recommended (see the W3C Note and Unicode Technical Report Unicode in XML & Other Markup Languages). Markup is needed to establish the default directionality of a document, and to change that where appropriate by creating nested embedding levels.
Markup is also required to disable the effects of the bidirectional algorithm for a specified range of text.
See the following GEO documents for background:
It may be sensible, when considering implementation approaches, to follow the lead of the XHTML 2.0 specification