L2/99-270

WG2 N2085

Title:��������������� Comments on ISO/IEC 10646-1, Second Edition text, Draft 2

Source:����������� Unicode Technical Committee, NCITS/L2

Status:������������ Joint Unicode/US Contribution

Action:������������ For Review and Disposition by JTC1/SC2/WG2

Date: �������������� September 9, 1999

This document provides comments on draft two of the second edition of ISO/IEC 10646-1. There are certain features of the Unicode Standard that many implementers find useful when providing support for the character encoding defined by ISO/IEC 10646 and Unicode. With our comments, we would like to bring two useful features to the attention of the implementers of ISO/IEC 10646 - the Unicode bidirectional rendering algorithm and the Unicode definitions of big-endian and little-endian forms of UTF-16, which may be used in data interchange. We hope that even at this late date,� these comments can be considered as input to draft two.���������

1. Referencing the Unicode Standard. To highlight, for character encoding implementers, the features offered by the Unicode Standard, add the following text in either section 1 Scope or 3 Normative references:

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� Both ISO/IEC 10646-1 and the Unicode Standard, Version 3.0 provide the identical character repertoire, names, and code values. Complementing ISO/IEC 10646, the Unicode Standard additionally provides character properties, algorithms, and definitions that are useful to implementers.

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2. The Unicode bidirectional algorithm. This bidirectional rendering algorithm is implemented widely by the industry. To bring it to the attention of ISO/IEC 10646 implementers, add the following text to section 19 Characters in bi-directional context:

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� The rendering of characters in a bi-directional context is correctly determined by following the bidirectional algorithm defined by the Unicode Standard, Version 3.0. This algorithm is applicable when using explicit bidirectional formatting characters (U+202A..U+202F) or when rendering bidirectional text implicitly.

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3. Non-Octet Encoding Forms. Driven by the need to successfully interchange UTF-16 data across computer systems based on different machine architectures, the Unicode Standard has added definitions for big-endian and little-endian encoding forms of UTF-16. To reference these definitions, add the following text to Annex C, either in section C.1 or as a new section between C.4 and C.5:

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� Non-Octet Encoding Forms

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� When not serialized as octets (see Clause 6.3), the order of octets in UTF-16 may be specified by agreement between sender and recipient. In particular, any of the encoding forms defined by the Unicode Standard, Version 3.0 (section 3.8) can be used:

����������� UTF-16: with optional use of signature

����������� UTF-16BE: ������ big-endian, with no signature

����������� UTF-16LE:�������� little-endian, with no signature

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