This file contains a set of reference Label Generation Rules (LGR) for the Chinese language for the second level. The starting point for the development of this LGR can be found in the related Root Zone LGR [RZ-LGR-2-Hani]. For details and additional background on the script, see "Proposal for a Chinese Script Root Zone LGR" Proposal-Han] including the appendices [Proposal-Chinese-Appendices]. Note that while it is the Chinese Script Root Zone LGR which forms the starting point the reference LGR defined here covers the Chinese Language. The format of this file follows [RFC 7940].
The Root Zone LGR for the Chinese script lists 19685 single code points. It is the union of CDNC IDN Table 2.0/2018 and dotAsia IDN Table. That repertoire is a subset of [Unicode 6.3]. For mor detail, see Section 5, "Repertoire" in [Proposal-Han]. (The proposal cited has been adopted for the Han script portion of the Root Zone LGR.)
For the second level, the repertoire is augmented by the ASCII digits and ASCII lowercase letters as well as U+002D HYPHEN, for a total of 19722 repertoire elements. Unlike many other non-Latin second level reference LGRs, the Chinese LGR includes the basic ASCII Latin set (a to z) because it is common practice in Chinese text to mix Han and ASCII. Therefore it does not create confusability or additional security risks in the context of a second level LGR for the Chinese language. It is also supported by current IDNA practice, see [200], for example.
Note: This LGR contains 62 code points from the Unicode block: CJK UNIFIED IDEOGRAPHS EXTENDED B.
Code points outside the Chinese language that are listed in this file are targets for out-of-repertoire variants and are identified by a reflexive (identity) variant of type "out-of-repertoire-var". They do not form part of the repertoire.
Each code point is tagged with the script or scripts that the code point is used with, one or more tag values denoting character category, and one or more references documenting sufficient justification for inclusion in the repertoire, see "References" below.
Any variants are blocked.
None.
This LGR is based on the reference LGR for the Chinese language for the 2nd Level, which has been developed by Michel Suignard and Asmus Freytag, based on the Root Zone LGR for Chinese script and information contained or referenced therein, see [RZ-LGR-2-Hani]. Suitable extensions for the second level have been applied according to the [Guidelines]. The original proposal for a Root Zone LGR for Chinese, that this LGR is based on, was developed by the Chinese Generation Panel (CGP). For methodology and contributors to the underlying Root Zone LGR, see Sections 4 and 9 in [Proposal-Han], as well as [RZ-LGR-Overview].
References [0] to [4] refer to the Unicode Standard versions in which corresponding code points were initially encoded. References [100], [200], [300], [400], [500], and [600] correspond to sources given in [Proposal-Han] for justifying the inclusion of for the corresponding code points. References [101], [102], [103], [201], [202], [203], [301], [501], [701], and [801] correspond to variant mapping types given in [Proposal-Han] for justifying these mapping types. Entries in the table may have multiple source reference values. Reference [150] indicates the source for common rules.
In addition, the following general references are cited in this document:
For additional detail on references cited in this document refer to the Table of References below. Where stable links to certain references are not publicly available, the data may be archived in [Proposal-Chinese-Appendices].