Root Zone LGR for script: Bengali (Beng) | lgr-4-bengali-script-05nov20-en

This document is mechanically formatted from the above XML file for the LGR. It provides additional summary data and explanatory text. The XML file remains the sole normative specification of the LGR.

Date | 2020-11-05
LGR Version | 4
Language | und-Beng
Scope | domain: "." (Root)
Unicode Version | 6.3.0

## Table of Contents

# 1 Description

# Root Zone Label Generation Rules for the Bengali (Bangla) script

## Overview

This file contains Label Generation Rules (LGR) for the Bengali (Bangla) script for the Root Zone. This LGR covers Assamese, Bengali, Manipuri and a number of other languages written with the Bengali script. For details and additional background on the script, see "Proposal for a Bengali Script Root Zone Label Generation Ruleset (LGR)" [Proposal-Bengali]. This file is one of a set of LGR files that together form an integrated LGR for the DNS Root Zone [RZ-LGR-4]. The format of this file follows [RFC 7940].

## Repertoire

The repertoire contains 61 code points for letters, as well as 9 code point sequences, for a total of 70 repertoire elements. Out of the nine sequences: two sequences override a WLE constraint; four sequences were defined for in-script variants; and the other three sequences were defined to restrict U+09BC (়) NUKTA from appearing in any context other than these sequences. Accordingly, while U+09BC (়) is not listed by itself, it brings the total of distinct code points to 62. For more detail, see Section 5, "Repertoire" in [Proposal-Bengali].

The repertoire is based on [MSR-4], which is a subset of Unicode 6.3 [Unicode 6.3].

As part of the Root Zone, this LGR includes neither digits nor the HYPHEN-MINUS.

Each code point or range 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. For code points that are part of the repertoire, comments identify the languages using the code point.

Code points outside the Bengali script that are listed in this file are targets for out-of-script variants and are identified by a reflexive (identity) variant of type "out-of-repertoire-var". They do not form part of the repertoire.

## Variants

This LGR defines in-script variants and cross-script variants as described in Section 6, "Variants", in [Proposal-Bengali]. There are three in-script variants; two sequence sets and one set for variation of RA. See Section 6.1 of [Proposal-Bengali]. There are four cross-script variants; two sets with Gurmukhi and the other two sets with Devanagari. See Section 6.2 of [Proposal-Bengali].

Variant Disposition: The in-script variant pair U+09B0 (র) / U+09F0 (ৰ) is of type "allocatable", thus allowing access to either user community. All other variants are of type "blocked", making labels that differ only by these variants mutually exclusive: whichever label containing either of these variants is chosen earlier, the other one equivalent variant label should be blocked. There is no preference among these variants.

The specification of variants in the Root Zone LGR follows the guidelines in [RFC 8228].

## Character Classes

Consonants: All consonants contain an implicit vowel. More details in Section 3.3.1, "The Consonants" of [Proposal-Bengali].

Hasanta: A special sign is needed whenever the implicit vowel in the preceding consonant is stripped off. This symbol is also known as the Halant or "Virama". More details in Section 3.3.2, "The Implicit Vowel Killer: Hasanta" of [Proposal-Bengali].

Vowels: Separate symbols exist for all "Swara" or Vowels in Bengali, which are pronounced independently either at the beginning of the word or after another vowel or consonant sound. To indicate a Vowel sound other than the implicit one, a Vowel sign (Matra) is attached to the consonant. More details in Section 3.3.3, " Vowels" of [Proposal-Bengali].

Anusvara: The Anusvara represents a homorganic nasal. It replaces a conjunct group of a Nasal Consonant+Halant+Consonant belonging to that particular barga or set. Before a non-barga consonant, the anusvara represents a nasal sound. More details in Section 3.3.4, "The Anusvara" of [Proposal-Bengali].

Candrabindu: Candrabindu denotes nasalization of the preceding vowel as in চাঁদ /cãd/ "moon" (U+099A U+09BE U+0981 U+09A6). This sign with a dot inside the half-moon mark is used as nasalization marker in many Indian scripts. More details in Section 3.3.5, "Nasalization: Candrabindu" of [Proposal-Bengali].

Visarga and Avagraha: The Visarga U+0983 (ঃ) is frequently used in Bengali loanwords borrowed from Sanskrit and represents a sound very close to /h/. More details in Section 3.3.7, "Visarga and Avagraha" of [Proposal-Bengali].

Ya-phala: There are two instances in Bangla where a Hasanta is preceded by a full vowel (U+0985 (অ) BENGALI LETTER A and U+098F (এ) BENGALI LETTER E). More details in Section 3.3.9, "Use of Ya-phala" of [Proposal-Bengali].

Ra-phala and Ref Sequences: RA+Hasanta (Repha or Ra-phala sequences). More details in Section 3.3.10, "Ra-phala and Ref Sequences" of [Proposal-Bengali].

Nukta: Nukta is not listed by itself in the repertoire; it is only included in three sequences. More details in Section 3.3.6, "Nukta" of [Proposal-Bengali].

Zero Width Non-joiner (ZWNJ) and Zero Width Joiner (ZWJ): These are not included in the repertoire. More details in Section 3.3.8, "Zero Width Non-joiner (U+200C) and Zero Width Joiner (U+200D)" of [Proposal-Bengali].

## Whole Label Evaluation (WLE) and Context Rules

### Default Whole Label Evaluation Rules and Actions

The LGR includes the set of required default WLE rules and actions applicable to the Root Zone and defined in [MSR-4]. They are marked with ⍟. The default prohibition on leading combining marks is equivalent to ensuring that a label only starts with a consonant or vowel.

### Bengali-specific Rules

These rules have been formulated as context rules suitable for adoption into an LGR specification.

The following symbols are used in the WLE rules:

- C → Consonant
- M → Kar (Matra)
- V → Vowel
- B → Onushshar (Anusvara)
- X → Bisarga (Visarga)
- D → Candrabindu
- H → Hasanta (Halant)
- Z → KhandaTa
- P → Ra-Hasanta
- S → (a/e) Ya-phala

The rules are:

- 1. C: C is a set of C and CN where CN is the set of normalized forms of {ড়,ঢ়,য়}
- 2. H: must be preceded by C
- 3. M: must be preceded by C
- 4. D: must be preceded by any of V, C, M
- 5. X: must be preceded by any of V, C, M, D
- 6. B: must be preceded by any of V, C, M, D
- 7. Z: must be preceded by any of V, C, M, D, B, X, P
- 8. V: CANNOT be preceded by H
- 9. S: CANNOT be preceded by H
- 10. U+09B0 (র) and U+09F0 (ৰ) CANNOT be mixed in the same label

More details in Section 7, "Whole Label Evaluation Rules (WLE)" of [Proposal-Bengali].

## Methodology and Contributors

The Root Zone LGR for the Bengali script was developed by the Neo-Brahmi Generation Panel (NBGP) the members of which have experience in linguistics and computational linguistics in a wide variety of languages written with Neo-Brahmi scripts. Under the Neo-Brahmi Generation Panel, there are nine scripts belonging to separate Unicode blocks. Each of these scripts has been assigned a separate LGR, with the Neo-Brahmi GP ensuring that the fundamental philosophy behind building each LGR is in sync with all other Brahmi derived scripts. For further details on methodology and contributors, see Sections 4 and 8 in [Proposal-Bengali], as well as [RZ-LGR-4-Overview].

## References

The following general references are cited in this document:

[MSR-4]
  Integration Panel, "Maximal Starting Repertoire — MSR-4 Overview and Rationale", 7 February 2019
  https://www.icann.org/en/system/files/files/msr-4-overview-25jan19-en.pdf
[Proposal-Bengali]
  Neo-Brahmi Generation Panel, “Proposal for a Bangla (Bengali) Script Root Zone Label Generation Rule-Set (LGR)”, 20 May 2020,
  https://www.icann.org/en/system/files/files/proposal-bangla-lgr-20may20-en.pdf
[RFC 7940]
  Davies, K. and A. Freytag, "Representing Label Generation Rulesets Using XML", RFC 7940, August 2016,
  http://www.rfc-editor.org/info/rfc7940.
[RFC 8228]
  A. Freytag, "Guidance on Designing Label Generation Rulesets (LGRs) Supporting Variant Labels", RFC 8228, August 2017,
  https://www.rfc-editor.org/info/rfc8228
[RZ-LGR-4]
  Integration Panel, "Label Generation Rules for the Root Zone — LGR-4", 05 November 2020 (XML),
  https://www.icann.org/sites/default/files/lgr/lgr-4-common-05nov20-en.xml
  non-normative HTML presentation:
  https://www.icann.org/sites/default/files/lgr/lgr-4-common-05nov20-en.html
[RZ-LGR-4-Overview]
  Integration Panel, "Root Zone Label Generation Rules - LGR-4: Overview and Summary", 05 November 2020 (PDF),
  https://www.icann.org/sites/default/files/lgr/lgr-4-overview-05nov20-en.pdf
[Unicode 6.3]
  The Unicode Consortium. The Unicode Standard, Version 6.3.0, (Mountain View, CA: The Unicode Consortium, 2013. ISBN 978-1-936213-08-5)
  http://www.unicode.org/versions/Unicode6.3.0/

For references consulted particularly in designing the repertoire for the Bengali script for the Root Zone please see details in the Table of References below. References [0] and [7] refer to the Unicode Standard versions in which the corresponding code points were initially encoded. References [101] and above correspond to sources given in [Proposal-Bengali] justifying the inclusion of the corresponding code points. Entries in the table may have multiple source reference values.

# 2 Repertoire

## Repertoire Summary

Number of elements in repertoire | 70
Out-of-repertoire variants | 4
Total entries in table | 74
Number of code points for each script |
Bengali | 61
Devanagari | 2
Gurmukhi | 2
Number of code points | 65
Number of sequences | 9
Longest code point sequence | 4
Code points defined via sequence | 1

## Repertoire by Code Point

The following table lists the repertoire by code point (or code point sequence). The data in the Script and Name column are extracted from the Unicode character database. Where a comment in the original LGR is equal to the character name, it has been suppressed.

Some code points that may be part of a valid label under this LGR only occur as part of one or more sequences. Such code points are not listed individually in the table.

For any code point or sequence for which a variant is defined, additional information is provided in the Variants column. Some code points or sequences listed in the following table are not part of the repertoire itself; they document targets for out-of-repertoire variant mappings as indicated. See also the legend provided below the table.

Code Point | Glyph | Script | Name | Ref | Tags | Required Context | Part of Repertoire | Variants | Comment
--- | --- | --- | --- | --- | --- | --- | --- | --- | ---
U+092E | म | Devanagari | DEVANAGARI LETTER MA | [0] |  |  | ✗ | set 1 | Not part of repertoire
U+093F | ि | Devanagari | DEVANAGARI VOWEL SIGN I | [0] |  |  | ✗ | set 2 | Not part of repertoire
U+0981 | ঁ | Bengali | BENGALI SIGN CANDRABINDU | [0], [101], [102], [103] | Candrabindu | follows-only-V-C-M | ✔ |  | Bangla, Manipuri, Assamese
U+0982 | ং | Bengali | BENGALI SIGN ANUSVARA | [0], [101], [102], [103] | Anusvara | follows-only-V-C-M-D | ✔ |  | Bangla, Manipuri, Assamese
U+0983 | ঃ | Bengali | BENGALI SIGN VISARGA | [0], [101], [102], [103] | Visarga | follows-only-V-C-M-D | ✔ |  | Bangla, Manipuri, Assamese
U+0985 | অ | Bengali | BENGALI LETTER A | [0], [101], [102], [103] | Vowel | not: follows-H | ✔ |  | Bangla, Manipuri, Assamese
U+0985 U+09CD U+09AF U+09BE | অ্যা | {Bengali} | BENGALI LETTER A + BENGALI SIGN VIRAMA + BENGALI LETTER YA + BENGALI VOWEL SIGN AA |  | [Vowel] + [Halant] + [Consonant] + [Matra] | not: follows-H | ✔ |  | Ya-Phalaa (s1): Bangla, Assamese
U+0986 | আ | Bengali | BENGALI LETTER AA | [0], [101], [102], [103] | Vowel | not: follows-H | ✔ |  | Bangla, Manipuri, Assamese
U+0987 | ই | Bengali | BENGALI LETTER I | [0], [101], [102], [103] | Vowel | not: follows-H | ✔ |  | Bangla, Manipuri, Assamese
U+0988 | ঈ | Bengali | BENGALI LETTER II | [0], [101], [102], [103] | Vowel | not: follows-H | ✔ |  | Bangla, Manipuri, Assamese
U+0989 | উ | Bengali | BENGALI LETTER U | [0], [101], [102], [103] | Vowel | not: follows-H | ✔ |  | Bangla, Manipuri, Assamese
U+098A | ঊ | Bengali | BENGALI LETTER UU | [0], [101], [102], [103] | Vowel | not: follows-H | ✔ |  | Bangla, Manipuri, Assamese
U+098B | ঋ | Bengali | BENGALI LETTER VOCALIC R | [0], [101], [102], [103] | Vowel | not: follows-H | ✔ |  | Bangla, Manipuri, Assamese
U+098F | এ | Bengali | BENGALI LETTER E | [0], [101], [102], [103] | Vowel | not: follows-H | ✔ |  | Bangla, Manipuri, Assamese
U+098F U+09CD U+09AF U+09BE | এ্যা | {Bengali} | BENGALI LETTER E + BENGALI SIGN VIRAMA + BENGALI LETTER YA + BENGALI VOWEL SIGN AA |  | [Vowel] + [Halant] + [Consonant] + [Matra] | not: follows-H | ✔ |  | Ya-Phalaa (s2): Bangla
U+0990 | ঐ | Bengali | BENGALI LETTER AI | [0], [101], [102], [103] | Vowel | not: follows-H | ✔ |  | Bangla, Manipuri, Assamese
U+0993 | ও | Bengali | BENGALI LETTER O | [0], [101], [102], [103] | Vowel | not: follows-H | ✔ |  | Bangla, Manipuri, Assamese
U+0994 | ঔ | Bengali | BENGALI LETTER AU | [0], [101], [102], [103] | Consonant |  | ✔ |  | Bangla, Manipuri, Assamese
U+0995 | ক | Bengali | BENGALI LETTER KA | [0], [101], [102], [103] | Consonant |  | ✔ |  | Bangla, Manipuri, Assamese
U+0996 | খ | Bengali | BENGALI LETTER KHA | [0], [101], [102], [103] | Consonant |  | ✔ |  | Bangla, Manipuri, Assamese
U+0997 | গ | Bengali | BENGALI LETTER GA | [0], [101], [102], [103] | Consonant |  | ✔ |  | Bangla, Manipuri, Assamese
U+0998 | ঘ | Bengali | BENGALI LETTER GHA | [0], [101], [102], [103] | Consonant |  | ✔ |  | Bangla, Manipuri, Assamese
U+0999 | ঙ | Bengali | BENGALI LETTER NGA | [0], [101], [102], [103] | Consonant |  | ✔ |  | Bangla, Manipuri, Assamese
U+099A | চ | Bengali | BENGALI LETTER CA | [0], [101], [102], [103] | Consonant |  | ✔ |  | Bangla, Manipuri, Assamese
U+099B | ছ | Bengali | BENGALI LETTER CHA | [0], [101], [102], [103] | Consonant |  | ✔ |  | Bangla, Manipuri, Assamese
U+099C | জ | Bengali | BENGALI LETTER JA | [0], [101], [102], [103] | Consonant |  | ✔ |  | Bangla, Manipuri, Assamese
U+099D | ঝ | Bengali | BENGALI LETTER JHA | [0], [101], [102], [103] | Consonant |  | ✔ |  | Bangla, Manipuri, Assamese
U+099E | ঞ | Bengali | BENGALI LETTER NYA | [0], [101], [102], [103] | Consonant |  | ✔ |  | Bangla, Manipuri, Assamese
U+099F | ট | Bengali | BENGALI LETTER TTA | [0], [101], [102], [103] | Consonant |  | ✔ |  | Bangla, Manipuri, Assamese
U+09A0 | ঠ | Bengali | BENGALI LETTER TTHA | [0], [101], [102], [103] | Consonant |  | ✔ |  | Bangla, Manipuri, Assamese
U+09A1 | ড | Bengali | BENGALI LETTER DDA | [0], [101], [102], [103] | Consonant |  | ✔ |  | Bangla, Manipuri, Assamese
U+09A1 U+09BC | ড় | {Bengali} | BENGALI LETTER DDA + BENGALI SIGN NUKTA | [0], [101], [102], [103] | [Consonant] + [] |  | ✔ |  | 09DC is the preferred code point, however it is not available for LGR as per the standards governing this LGR development
U+09A2 | ঢ | Bengali | BENGALI LETTER DDHA | [0], [101], [102], [103] | Consonant |  | ✔ |  | Bangla, Manipuri, Assamese,
U+09A2 U+09BC | ঢ় | {Bengali} | BENGALI LETTER DDHA + BENGALI SIGN NUKTA | [0], [101], [102], [103] | [Consonant] + [] |  | ✔ |  | 09DD is the preferred code point, however it is not available for LGR as per the standards governing this LGR development
U+09A3 | ণ | Bengali | BENGALI LETTER NNA | [0], [101], [102], [103] | Consonant |  | ✔ |  | Bangla, Manipuri, Assamese
U+09A4 | ত | Bengali | BENGALI LETTER TA | [0], [101], [102], [103] | Consonant |  | ✔ |  | Bangla, Manipuri, Assamese
U+09A5 | থ | Bengali | BENGALI LETTER THA | [0], [101], [102], [103] | Consonant |  | ✔ |  | Bangla, Manipuri, Assamese
U+09A6 | দ | Bengali | BENGALI LETTER DA | [0], [101], [102], [103] | Consonant |  | ✔ |  | Bangla, Manipuri, Assamese
U+09A7 | ধ | Bengali | BENGALI LETTER DHA | [0], [101], [102], [103] | Consonant |  | ✔ |  | Bangla, Manipuri, Assamese
U+09A8 | ন | Bengali | BENGALI LETTER NA | [0], [101], [102], [103] | Consonant |  | ✔ |  | Bangla, Manipuri, Assamese
U+09A8 U+09CD U+09A5 | ন্থ | {Bengali} | BENGALI LETTER NA + BENGALI SIGN VIRAMA + BENGALI LETTER THA |  | [Consonant] + [Halant] + [Consonant] |  | ✔ | set 3 | Bengali variant
U+09A8 U+09CD U+09B9 | ন্হ | {Bengali} | BENGALI LETTER NA + BENGALI SIGN VIRAMA + BENGALI LETTER HA |  | [Consonant] + [Halant] + [Consonant] |  | ✔ | set 3 | Bengali variant
U+09AA | প | Bengali | BENGALI LETTER PA | [0], [101], [102], [103] | Consonant |  | ✔ |  | Bangla, Manipuri, Assamese
U+09AB | ফ | Bengali | BENGALI LETTER PHA | [0], [101], [102], [103] | Consonant |  | ✔ |  | Bangla, Manipuri, Assamese
U+09AC | ব | Bengali | BENGALI LETTER BA | [0], [101], [102], [103] | Consonant |  | ✔ |  | Bangla, Manipuri, Assamese
U+09AD | ভ | Bengali | BENGALI LETTER BHA | [0], [101], [102], [103] | Consonant |  | ✔ |  | Bangla, Manipuri, Assamese
U+09AE | ম | Bengali | BENGALI LETTER MA | [0], [101], [102], [103] | Consonant |  | ✔ | set 1 | Bangla, Manipuri, Assamese
U+09AF | য | Bengali | BENGALI LETTER YA | [0], [101], [102], [103] | Consonant |  | ✔ |  | Bangla, Manipuri, Assamese
U+09AF U+09BC | য় | {Bengali} | BENGALI LETTER YA + BENGALI SIGN NUKTA | [0], [101], [102], [103] | [Consonant] + [] |  | ✔ |  | 09DF is the preferred code point, however it is not available for LGR as per the standards governing this LGR development
U+09B0 | র | Bengali | BENGALI LETTER RA | [0], [101], [102] | C2, Consonant |  | ✔ | set 4 | Bangla, Manipuri
U+09B2 | ল | Bengali | BENGALI LETTER LA | [0], [101], [102], [103] | Consonant |  | ✔ |  | Bangla, Manipuri, Assamese
U+09B6 | শ | Bengali | BENGALI LETTER SHA | [0], [101], [102], [103] | Consonant |  | ✔ |  | Bangla, Manipuri, Assamese
U+09B7 | ষ | Bengali | BENGALI LETTER SSA | [0], [101], [102], [103] | Consonant |  | ✔ |  | Bangla, Manipuri, Assamese
U+09B8 | স | Bengali | BENGALI LETTER SA | [0], [101], [102], [103] | Consonant |  | ✔ |  | Bangla, Manipuri, Assamese
U+09B8 U+09CD U+09A5 | স্থ | {Bengali} | BENGALI LETTER SA + BENGALI SIGN VIRAMA + BENGALI LETTER THA |  | [Consonant] + [Halant] + [Consonant] |  | ✔ | set 5 | Bengali variant
U+09B8 U+09CD U+09B9 | স্হ | {Bengali} | BENGALI LETTER SA + BENGALI SIGN VIRAMA + BENGALI LETTER HA |  | [Consonant] + [Halant] + [Consonant] |  | ✔ | set 5 | Bengali variant
U+09B9 | হ | Bengali | BENGALI LETTER HA | [0], [101], [102], [103] | Consonant |  | ✔ |  | Bangla, Manipuri, Assamese
U+09BE | া | Bengali | BENGALI VOWEL SIGN AA | [0], [101], [102], [103] | Matra | follows-only-C | ✔ |  | Bangla, Manipuri, Assamese
U+09BF | ি | Bengali | BENGALI VOWEL SIGN I | [0], [101], [102], [103] | Matra | follows-only-C | ✔ | set 2 | Bangla, Manipuri, Assamese
U+09C0 | ী | Bengali | BENGALI VOWEL SIGN II | [0], [101], [102], [103] | Matra | follows-only-C | ✔ |  | Bangla, Manipuri, Assamese
U+09C1 | ু | Bengali | BENGALI VOWEL SIGN U | [0], [101], [102], [103] | Matra | follows-only-C | ✔ |  | Bangla, Manipuri, Assamese
U+09C2 | ূ | Bengali | BENGALI VOWEL SIGN UU | [0], [101], [102], [103] | Matra | follows-only-C | ✔ |  | Bangla, Manipuri, Assamese
U+09C3 | ৃ | Bengali | BENGALI VOWEL SIGN VOCALIC R | [0], [101], [102], [103] | Matra | follows-only-C | ✔ |  | Bangla, Manipuri, Assamese
U+09C4 | ৄ | Bengali | BENGALI VOWEL SIGN VOCALIC RR | [0], [101], [103] | Matra | follows-only-C | ✔ |  | Bangla, Assamese
U+09C7 | ে | Bengali | BENGALI VOWEL SIGN E | [0], [101], [102], [103] | Matra | follows-only-C | ✔ |  | Bangla, Manipuri, Assamese
U+09C8 | ৈ | Bengali | BENGALI VOWEL SIGN AI | [0], [101], [102], [103] | Matra | follows-only-C | ✔ |  | Bangla, Manipuri, Assamese
U+09CB | ো | Bengali | BENGALI VOWEL SIGN O | [0], [101], [102], [103] | Matra | follows-only-C | ✔ |  | Bangla, Manipuri, Assamese
U+09CC | ৌ | Bengali | BENGALI VOWEL SIGN AU | [0], [101], [102], [103] | Matra | follows-only-C | ✔ |  | Bangla, Manipuri, Assamese
U+09CD | ্ | Bengali | BENGALI SIGN VIRAMA | [0], [101], [102], [103] | Halant | follows-only-C | ✔ |  | Bangla, Manipuri, Assamese
U+09CE | ৎ | Bengali | BENGALI LETTER KHANDA TA | [7], [101], [102], [103] | Consonant, KhandaTa | follows-only-V-C-M-D-B-X-P | ✔ |  | Bangla, Manipuri, Assamese
U+09F0 | ৰ | Bengali | BENGALI LETTER RA WITH MIDDLE DIAGONAL | [0], [103] | C2, Consonant |  | ✔ | set 4 | Assamese
U+09F1 | ৱ | Bengali | BENGALI LETTER RA WITH LOWER DIAGONAL | [0], [102], [103] | Consonant |  | ✔ |  | Manipuri, Assamese
U+0A38 | ਸ | Gurmukhi | GURMUKHI LETTER SA | [0] |  |  | ✗ | set 1 | Not part of repertoire
U+0A3F | ਿ | Gurmukhi | GURMUKHI VOWEL SIGN I | [0] |  |  | ✗ | set 2 | Not part of repertoire

Legend

Throughout this LGR, a code point sequence may be annotated with a string in ALL CAPS that is constructed on the same principle as a name for a Unicode Named Sequence. No claim is made that a sequence thus annotated is in fact a named sequence, nor that the annotation in such case actually corresponds to the formal name of a named sequence.

Code Point
  A code point or code point sequence.
Glyph
  The shape displayed depends on the fonts available to your browser.
Script
  Shows the script property value from the Unicode Character Database. Combining marks may have the value Inherited and code points used with more than one script may have the value Common. Sequences are annotated with a set of all distinct script values.
Name
  Shows the character or sequence name from the Unicode Character Database. Named sequences are listed with their normative names, for ad-hoc sequences the individual names are shown separated by “+”.
Ref
  Links to the references associated with the code point or sequence, if any.
Tags
  LGR-defined tag values. Any tags matching the Unicode script property are suppressed in this view. For sequences, the tags for all member code points are shown for information; sequences as such do not have tags.
Required Context
  Link to a rule defining the required context a code point or sequence must satisfy. If prefixed by “not:” identifies a context that must not occur.
Variants
  Link to the variant set the code point or sequence is a member of, except where a coded point or sequence maps only to itself, in which case the type of that mapping is listed.
Comment
  The comment as given in the XML file. However, if the comment for this row consists only of the code point or sequence name, it is suppressed in this view. By convention, comments starting with “=” denote an alias. If present, the symbol ⍟ marks a default item shared among a set of LGRs.
✔ - core repertoire
  A check mark in the Part-of-repertoire column indicates a code point is part of the core repertoire.
✗ - out-of-repertoire
  A code point shown with ✗ is not part of the repertoire. It is listed only because it is the target of an out-of-repertoire-var variant mapping.

# 3 Variant Sets

## Variant Set Summary

Number of variant sets | 5
Largest variant set | 3
Ordinary Variants by Type |
allocatable | 2
blocked | 16
Reflexive Variants by Type |
out-of-repertoire-var | 4

The following tables list all variant sets defined in this LGR, except for singleton sets. Each table lists all variant mapping pairs of the set; one per row. Mappings are assumed to be symmetric: each row documents both forward (→) and reverse (←) mapping directions. In each table, the mappings are sorted by Source value in ascending code point order; shading is used to group mappings from the same source code point or sequence.

Where the type of both forward and reverse mappings are the same, a single value is given in the Type column; otherwise the types for forward and reverse mappings, as well as comments and references, are listed above one another. For summary counts, both forward and reverse mappings are always counted separately.

A mapping where source and target are the same is reflexive. Variant sets consisting of only a single reflexive mapping are not shown as a set. Instead, the variant type of the mapping is listed in the Variants column of the Repertoire by Code Point table. Reflexive mappings that are part of a larger set are indicated with a “≡” and are counted once per entry.

In any LGR with variant specifications that are well behaved, all members within each variant set are defined as variants of each other; the mappings in each set are symmetric and transitive; and all variant sets are disjoint.

Common Legend

Source
  By convention, the smaller of the two code points in a variant mapping pair.
Target
  By convention, the larger of the two code points in a variant mapping pair.
Glyph
  The shape displayed for source or target depends on the fonts available to your browser.
→ - forward
  Indicates that Type, Ref and Comment apply to the mapping from source to target.
← - reverse
  Indicates that Type, Ref and Comment apply to the reverse mapping from target to source.
↔ - both
  Indicates that Type, Ref and Comment apply to both forward and reverse mapping.
≡ - reflexive
  Indicates that Type, Ref and Comment are for a reflexive mapping where source equals target.
Type
  The type of the variant mapping. There are some predefined variant types such as “allocatable” and “blocked”, while others are defined specifically for each LGR. A reflexive variant type “out-of-repertoire-var” designates the target as not part of the repertoire; it is required as target for one or more variant mappings that cross repertoire boundaries.
Ref
  One or more reference IDs (optional). A “/” separates references for reverse / forward mappings, if different.
Comment
  A descriptive comment (optional). A “/” separates comments for reverse / forward mappings, if different.

### Variant Set 1 — 3 Members

Source | Glyph | Target | Glyph |  | Type | Ref | Comment
--- | --- | --- | --- | --- | --- | --- | ---
092E | म | 092E | म | ≡ | out-of-repertoire-var |  | Out-of-repertoire
092E | म | 09AE | ম | ↔ | blocked |  | Cross-script homoglyph
092E | म | 0A38 | ਸ | ↔ | blocked |  | Cross-script homoglyph
09AE | ম | 0A38 | ਸ | ↔ | blocked |  | Cross-script homoglyph
0A38 | ਸ | 0A38 | ਸ | ≡ | out-of-repertoire-var |  | Out-of-repertoire

### Variant Set 2 — 3 Members

Source | Glyph | Target | Glyph |  | Type | Ref | Comment
--- | --- | --- | --- | --- | --- | --- | ---
093F | ि | 093F | ि | ≡ | out-of-repertoire-var |  | Out-of-repertoire
093F | ि | 09BF | ি | ↔ | blocked |  | Cross-script homoglyph
093F | ि | 0A3F | ਿ | ↔ | blocked |  | Cross-script homoglyph
09BF | ি | 0A3F | ਿ | ↔ | blocked |  | Cross-script homoglyph
0A3F | ਿ | 0A3F | ਿ | ≡ | out-of-repertoire-var |  | Out-of-repertoire

### Variant Set 3 — 2 Members

Source | Glyph | Target | Glyph |  | Type | Ref | Comment
--- | --- | --- | --- | --- | --- | --- | ---
09A8 09CD 09A5 | ন্থ | 09A8 09CD 09B9 | ন্হ | ↔ | blocked |  | Bengali variant

### Variant Set 4 — 2 Members

Source | Glyph | Target | Glyph |  | Type | Ref | Comment
--- | --- | --- | --- | --- | --- | --- | ---
09B0 | র | 09F0 | ৰ | ↔ | allocatable |  | Bengali variant

### Variant Set 5 — 2 Members

Source | Glyph | Target | Glyph |  | Type | Ref | Comment
--- | --- | --- | --- | --- | --- | --- | ---
09B8 09CD 09A5 | স্থ | 09B8 09CD 09B9 | স্হ | ↔ | blocked |  | Bengali variant

# 4 Classes, Rules and Actions

## 4.1 Character Classes

The following table lists all named and implicit classes with their definition and a list of their members intersected with the current repertoire (for larger classes, this list is elided).

Name | Definition | Count | Members or Ranges | Ref | Comment
--- | --- | --- | --- | --- | ---
C-single | Tag=Consonant | 36 | {0994-09A8 09AA-09B0 09B2 09B6-09B9 09CE 09F0-09F1} |  | Any Bengali consonant
V | Tag=Vowel | 10 | {0985-098B 098F-0990 0993} |  | Any Bengali vowel letter
M | Tag=Matra | 11 | {09BE-09C4 09C7-09C8 09CB-09CC} |  | Any Bengali vowel sign (matra)
H | Tag=Halant | 1 | {09CD} |  | The Bengali Hasanta (Halant / Virama)
B | Tag=Anusvara | 1 | {0982} |  | The Bengali Onushshar (Anusvara)
X | Tag=Visarga | 1 | {0983} |  | The Bengali Bisarga (Visarga)
D | Tag=Candrabindu | 1 | {0981} |  | The Bengali Candrabindu
C2 | Tag=C2 | 2 | {09B0 09F0} |  | Any Bengali consonant from set C2
implicit | Tag=KhandaTa | 1 | {09CE} |  | The character tagged as KhandaTa
implicit | Tag=sc:Beng | 61 | {0981-0983 0985-098B 098F-0990 0993-09A8 09AA-09B0 09B2 09B6-09B9 09BE-09C4 09C7-09C8 09CB-09CE 09F0-09F1} |  | Any character tagged as Bengali
implicit | Tag=sc:Deva | 2 | {092E 093F} |  | Any character tagged as Devanagari
implicit | Tag=sc:Guru | 2 | {0A38 0A3F} |  | Any character tagged as Gurmukhi

Legend

Members or Ranges
  Lists the members of the class as code points (xxx) or as ranges of code points (xxx-yyy). Any class too numerous to list in full is elided with "...".
Tag=ttt
  A named or implicit class defined by all code points that share the given tag value (ttt).
Implicit
  An anonymous class implicitly defined based on tag value for which there is no named equivalent.

## 4.2 Whole label evaluation and context rules

The following table lists all named rules defined in the LGR and indicates whether they are used as trigger in an action or as context (when or not-when) for a code point or variant.

Name | Regular Expression | Used as Trigger | Anchor | Used as Context | Ref | Comment
--- | --- | --- | --- | --- | --- | ---
C-RRA | `\u09A1\u09BC` |  |  |  |  | NFC form of BENGALI LETTER RRA
C-RHA | `\u09A2\u09BC` |  |  |  |  | NFC form of BENGALI LETTER RHA
C-YYA | `\u09AF\u09BC` |  |  |  |  | NFC form of BENGALI LETTER YYA
C | `[:C-single:]|(:C-RRA:)|(:C-RHA:)|(:C-YYA:)` |  |  |  |  | Section 7, WLE1: All consonants in the LGR repertoire; single code points and sequences
leading-combining-mark | `(start)[[\p{gc=Mn}] ∪ [\p{gc=Mc}]]` | ✔ |  |  |  | Default WLE rule matching labels with leading combining marks ⍟
follows-only-C | `((:C:))← ⚓` |  | ✔ | C |  | Section 7, WLE 2: H: must be preceded by C ; WLE 3: M: must be preceded by C
follows-only-V-C-M | `([:V:]|(:C:)|[:M:])← ⚓` |  | ✔ | C |  | Section 7, WLE 4: D: must be preceded by any of V, C, M
follows-only-V-C-M-D | `([:V:]|(:C:)|[:M:]|[:D:])← ⚓` |  | ✔ | C |  | Section 7, WLE 5: X: must be preceded by any of V, C, M, D; WLE 6: B: must be preceded by any of V, C, M, D
P | `[:C2:][:H:]` |  |  |  |  | Ra-Hasanta, defined for use in WLE-7
follows-only-V-C-M-D-B-X-P | `([:V:]|(:C:)|[:M:]|[:D:]|[:B:]|[:X:]|(:P:))← ⚓` |  | ✔ | C |  | Section 7, WLE 7: Khanda Ta must be preceded by V, C, M, D, B, X, P
follows-H | `([:H:])← ⚓` |  | ✔ | C |  | Section 7, WLE 8: V cannot be preceded by H, WLE 9: S cannot be preceded by H
no-mix-09B0-09F0 | `(\u09B0.*\u09F0)|(\u09F0.*\u09B0)` | ✔ |  |  |  | Section 7, WLE 10: U+09B0 (র) and U+09F0 (ৰ) cannot be mixed.

Legend

Used as Trigger
  This rule triggers one of the actions listed below.
Used as Context
  This rule defines a required or prohibited context for a code point C or variant V.
Anchor
  This rule has a placeholder for the code point for which it is evaluated.
Regular Expression
  A regular expression equivalent to the rule, shown in a modified notation as noted:
⚓ - context anchor
  Placeholder for the actual code point when a context is evaluated. The code point must occur at the position corresponding to the anchor. Rules containing an anchor cannot be used as triggers.
(...)← - look-behind
  If present encloses required context preceding the anchor.
→(..) - look-ahead
  If present encloses required context following the anchor.
(: :) - rule reference
  Non-recursive reference to a named rule.
(... | ...) - choice
  When there is more than one alternative in a rule, the choices are separated by the alternation operator (...|...).
start or end
  (start) matches the start of the label; (end) matches the end of the label.
. - any code point
  . matches any code point.
*, +, ?, {n,m} - count operators
  * indicates 0 or more, + indicates one or more, and ? indicates up to one instance. {n,m} indicates at least n and at most m instances.
[: :] - named or implicit character set
  Reference to a named character set [:name:] or an implicit character set [:tag:]. A leading “^” before name or tag indicates the set complement.
[\p{ }] - property character set
  Set of all characters matching a given value for a Unicode property [\p{prop=val}]. Note: uppercase “\P” defines the complement of a property set.
∪, ∩, ∖, ∆ - set operators
  Sets may be combined by set operators (∪ = union, ∩ = intersection, ∖ = difference, ∆ = symmetric difference).
⍟ - default rule
  Rules marked with ⍟ are included by default and may or may not be triggered by any possible label under this LGR.

## 4.3 Actions

The following table lists the actions that are used to assign dispositions to labels and variant labels based on the specified conditions. The order of actions defines their precedence: the first action triggered by a label is the one defining its disposition.

# | Condition | Rule / Variant Set |  | Disposition | Ref | Comment
--- | --- | --- | --- | --- | --- | ---
1 | if label matches | leading-combining-mark | → | invalid |  | labels with leading combining marks are invalid ⍟
2 | if label matches | no-mix-09B0-09F0 | → | invalid |  | WLE 10: U+09B0 and U+09F0 cannot be mixed.
3 | if at least one variant is in | {out-of-repertoire-var} | → | invalid |  | any variant label with a code point out of repertoire is invalid ⍟
4 | if at least one variant is in | {blocked} | → | blocked |  | any variant label containing blocked variants is blocked ⍟
5 | if each variant is in | {allocatable} | → | allocatable |  | variant labels with all variants allocatable are allocatable ⍟
6 | if any label (catch-all) |  | → | valid |  | catch all (default action) ⍟

Legend

{...} - variant type set
  In the “Rule/Variant Set” column, the notation {...} means a set of variant types.
⍟ - default action
  Actions marked with ⍟ are included by default and may or may not be triggered by any possible label under this LGR.

# 5 Table of References

The following lists the references cited for specific code points, variants, classes, rules or actions in this LGR. For General references refer to the "References" section in the Description.

[0] | The Unicode Standard 1.1 Any code point originally encoded in Unicode 1.1
[7] | The Unicode Standard 4.1 Any code point originally encoded in Unicode 4.1
[101] | Wikipedia, Bengali alphabet, accessed on 2017-11-25 https://en.wikipedia.org/wiki/Bengali_alphabet
[102] | Bengali alphabet for Manipuri, found in Omniglot, Manipuri (Meeteilon/ Meithei), accessed on 20.10.2019 https://www.omniglot.com/writing/manipuri.htm
[103] | Omniglot, Assamese (অসমীয়া), accessed on 2020-04-28 https://www.omniglot.com/writing/assamese.htm