Root Zone LGR for script und-Sinh (Sinhala) lgr-3-Sinhala-Script-25apr19-en

This document is mechanically formatted from the 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 2019-04-25
LGR Version 3
Language und-Sinh
Scope domain: "." (Root)
Unicode Version 6.3.0

Table of Contents

1 Description

Root Zone Label Generation Rules for the Sinhala Script

Overview

This file contains Label Generation Rules (LGR) for the Sinhala script for the Root zone. For more details on this LGR and its development, see "Proposal for a Sinhala Script Root Zone Label Generation Rules-Set (LGR)" [Proposal]. The format of this file follows [RFC 7940].

Repertoire

According to Section 5, "Repertoire" in [Proposal], the Sinhala LGR contains 72 unique code points. The addition of 4 sequences used in the definition of variants brings the total repertoire entries to 76. The repertoire covers the Sinhala language as written with the Sinhala script.

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

Each code point is tagged with the script or scripts that the code point is used with, a category value, and one or more references documenting sufficient justification for inclusion in the repertoire, see "References" below.

Variants

According to Section 6, "Variants", in [Proposal], this LGR defines variants within Sinhala which can cause confusion for even a careful observer. There are no cross-script variants, though some confusing cases are identified in [Proposal].

Variant Disposition: All 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 would be delegated any other equivalent label should be blocked. There is no preference among these variants.

This LGR does not define allocatable variants.

Context Rules for Variants: for some of the variants defined in this LGR the sequences or code points making up source and target are constrained by explicit context rules on the code points (or by implicit context rules defined for the adjacent code points). In such a case, any variants may require context rules that match the intersection between the effective contexts for both source and target; otherwise, a sequence might be considered valid in some variant label when it would not be valid in an equivalent context in an original label. Symmetry requires the same context rule for both forward and reverse mappings.

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

Character Classes

As most Brahmi-derived scripts, Sinhala is an alphasyllabary writing system and written from left to right. All the categories of Consonants, Vowels, Matras, Halant, Anusvara, Visarga and Sannjakas are discussed below.

Consonants: There are 40 consonants in Sinhala alphabet and 38 of them are selected for inclusion. Its consonants imply inherent vowel a(අ) when they are used without dependent vowels. Absence of the inherent vowel is marked by adding hal kirima (remover of the inherent vowel) to the consonant; thus ක /ka/ but ක් /k/, and ව /va/ but ව් /v/. More details in Section 3.3.1, "The Consonants" of the [Proposal].

Vowels and Matras: There are separate symbols (dependent vowels) for all the vowels except the inherent vowel අ in Sinhala. Independent vowels are used at the beginning of a word and dependent vowels (matras) are used after consonants. More details in Section 3.3.2, "The Vowels" of the [Proposal].

Halanta: The Halanta, which is also called halkirima or hallakuna, is encoded as U+0DCA ( ් ) SINHALA SIGN AL-LAKUNA. This sign is used to remove the inherent vowel of the consonants in Sinhala, and to join consonants and form conjunct characters. More details in Section 3.3.3, "Halanta: The Inherent Vowel Remover" of the [Proposal].

Anusvara: U+0D82 ( ං ) SINHALA SIGN ANUSVARAYA, pronounced /ŋ/, represents all the nasals. It can be preceded by any sign except halanta (U+0DCA). More details in Section 3.3.4, "The Anusvara" of the [Proposal].

Visarga: U+0D83 ( ඃ ) SINHALA SIGN VISARGAYA is a rarely used sign and pronounced as /h/. It can be preceded by any sign except halanta (U+0DCA). More details in Section 3.3.5, "The Visarga" of the [Proposal].

Sannjakas: There are five separate letters for prenasalized voiced stops called sannjakas in Sinhala. From among these, ඦ is not frequently used. One specification of Sannjakas is they cannot be followed by halanta. More details in Section 3.3.6, "Sannjakas" of the [Proposal].

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.

Sinhala-specific Rules

These rules have been formulated so that they can be adopted for LGR specification.

The following symbols are used in the WLE rules:
C → Consonant
M → Matra / Vowel Signs
V → Vowel
B → Anusvara (Bindu)
X → Visarga
H → Halanta / Virama
J → Sannjaka

The rules are:

The following context rules apply to code points in variant sets to ensure the variant transitivity.

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

Methodology and Contributors

The Sinhala LGR was developed by the Sinhala Generation Panel in consultation with the Neo-Brahmi Generation Panel. For methodology and contributors, see Sections 4 and 8 of [Proposal].

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]
Sinhala Generation Panel, “Proposal for a Sinhala Script Root Zone Label Generation Ruleset (LGR)”, 22 April 2019,
https://www.icann.org/en/system/files/files/proposal-sinhala-lgr-22apr19-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
[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/

2 Repertoire

Summary

Number of elements in Repertoire 76
Number of code points 72
Number of sequences 4
Longest code point sequence 2

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.

For any code point or sequence for which a variant is defined, additional information is provided in the Variants column. See also the legend provided below the table.

Code
Point
Glyph Script Name Ref Tags Required Context Variants Comment
U+0D82 Sinhala SINHALA SIGN ANUSVARAYA [102], [201] Anusvara follows-V-C-J-or-M    
U+0D83 Sinhala SINHALA SIGN VISARGAYA [102], [201] Visarga follows-V-C-or-M    
U+0D85 Sinhala SINHALA LETTER AYANNA [102], [201] Vowel      
U+0D86 Sinhala SINHALA LETTER AAYANNA [102], [201] Vowel      
U+0D87 Sinhala SINHALA LETTER AEYANNA [102], [201] Vowel      
U+0D88 Sinhala SINHALA LETTER AEEYANNA [102], [201] Vowel      
U+0D89 Sinhala SINHALA LETTER IYANNA [102], [201] Vowel      
U+0D8A Sinhala SINHALA LETTER IIYANNA [102], [201] Vowel      
U+0D8B Sinhala SINHALA LETTER UYANNA [102], [201] Vowel      
U+0D8C Sinhala SINHALA LETTER UUYANNA [102], [201] Vowel      
U+0D8D Sinhala SINHALA LETTER IRUYANNA [102], [201] Vowel   set 1  
U+0D91 Sinhala SINHALA LETTER EYANNA [102], [201] Vowel   set 2  
U+0D92 Sinhala SINHALA LETTER EEYANNA [102], [201] Vowel   set 3  
U+0D93 Sinhala SINHALA LETTER AIYANNA [102], [201] Vowel   set 4  
U+0D94 Sinhala SINHALA LETTER OYANNA [102], [201] Vowel   set 5  
U+0D95 Sinhala SINHALA LETTER OOYANNA [102], [201] Vowel      
U+0D96 Sinhala SINHALA LETTER AUYANNA [102], [201] Vowel      
U+0D9A Sinhala SINHALA LETTER ALPAPRAANA KAYANNA [102], [201] Consonant      
U+0D9B Sinhala SINHALA LETTER MAHAAPRAANA KAYANNA [102], [201] Consonant   set 6  
U+0D9C Sinhala SINHALA LETTER ALPAPRAANA GAYANNA [102], [201] Consonant      
U+0D9D Sinhala SINHALA LETTER MAHAAPRAANA GAYANNA [102], [201] Consonant   set 7  
U+0D9D U+0DD8 ඝෘ [Sinhala] SINHALA LETTER MAHAAPRAANA GAYANNA + SINHALA VOWEL SIGN GAETTA-PILLA [102], [201]     set 1 variant of IRUYANNA
U+0D9F Sinhala SINHALA LETTER SANYAKA GAYANNA [102], [201] Sannjaka      
U+0DA0 Sinhala SINHALA LETTER ALPAPRAANA CAYANNA [102], [201] Consonant   set 8  
U+0DA1 Sinhala SINHALA LETTER MAHAAPRAANA CAYANNA [102], [201] Consonant      
U+0DA2 Sinhala SINHALA LETTER ALPAPRAANA JAYANNA [102], [201] Consonant      
U+0DA3 Sinhala SINHALA LETTER MAHAAPRAANA JAYANNA [102], [201] Consonant      
U+0DA4 Sinhala SINHALA LETTER TAALUJA NAASIKYAYA [102], [201] Consonant      
U+0DA5 Sinhala SINHALA LETTER TAALUJA SANYOOGA NAAKSIKYAYA [102], [201] Consonant      
U+0DA7 Sinhala SINHALA LETTER ALPAPRAANA TTAYANNA [102], [201] Consonant      
U+0DA8 Sinhala SINHALA LETTER MAHAAPRAANA TTAYANNA [102], [201] Consonant      
U+0DA9 Sinhala SINHALA LETTER ALPAPRAANA DDAYANNA [102], [201] Consonant      
U+0DAA Sinhala SINHALA LETTER MAHAAPRAANA DDAYANNA [102], [201] Consonant      
U+0DAB Sinhala SINHALA LETTER MUURDHAJA NAYANNA [102], [201] Consonant      
U+0DAC Sinhala SINHALA LETTER SANYAKA DDAYANNA [102], [201] Sannjaka      
U+0DAD Sinhala SINHALA LETTER ALPAPRAANA TAYANNA [102], [201] Consonant      
U+0DAE Sinhala SINHALA LETTER MAHAAPRAANA TAYANNA [102], [201] Consonant      
U+0DAF Sinhala SINHALA LETTER ALPAPRAANA DAYANNA [102], [201] Consonant      
U+0DB0 Sinhala SINHALA LETTER MAHAAPRAANA DAYANNA [102], [201] Consonant      
U+0DB1 Sinhala SINHALA LETTER DANTAJA NAYANNA [102], [201] Consonant      
U+0DB3 Sinhala SINHALA LETTER SANYAKA DAYANNA [102], [201] Sannjaka      
U+0DB4 Sinhala SINHALA LETTER ALPAPRAANA PAYANNA [102], [201] Consonant      
U+0DB5 Sinhala SINHALA LETTER MAHAAPRAANA PAYANNA [102], [201] Consonant   set 2  
U+0DB5 U+0DCA ඵ් [Sinhala] SINHALA LETTER MAHAAPRAANA PAYANNA + SINHALA SIGN AL-LAKUNA [102], [201]     set 3 variant of EEYANNA
U+0DB5 U+0DD9 ඵෙ [Sinhala] SINHALA LETTER MAHAAPRAANA PAYANNA + SINHALA VOWEL SIGN KOMBUVA [102], [201]     set 4 variant of AIYANNA
U+0DB6 Sinhala SINHALA LETTER ALPAPRAANA BAYANNA [102], [201] Consonant   set 6  
U+0DB7 Sinhala SINHALA LETTER MAHAAPRAANA BAYANNA [102], [201] Consonant   set 9  
U+0DB8 Sinhala SINHALA LETTER MAYANNA [102], [201] Consonant      
U+0DB9 Sinhala SINHALA LETTER AMBA BAYANNA [102], [201] Sannjaka   set 5  
U+0DBA Sinhala SINHALA LETTER YAYANNA [102], [201] Consonant      
U+0DBB Sinhala SINHALA LETTER RAYANNA [102], [201] Consonant      
U+0DBD Sinhala SINHALA LETTER DANTAJA LAYANNA [102], [201] Consonant      
U+0DC0 Sinhala SINHALA LETTER VAYANNA [102], [201] Consonant   set 8  
U+0DC1 Sinhala SINHALA LETTER TAALUJA SAYANNA [102], [201] Consonant      
U+0DC2 Sinhala SINHALA LETTER MUURDHAJA SAYANNA [102], [201] Consonant      
U+0DC3 Sinhala SINHALA LETTER DANTAJA SAYANNA [102], [201] Consonant   set 7  
U+0DC3 U+0DD8 සෘ [Sinhala] SINHALA LETTER DANTAJA SAYANNA + SINHALA VOWEL SIGN GAETTA-PILLA [102], [201]     set 1 variant of IRUYANNA
U+0DC4 Sinhala SINHALA LETTER HAYANNA [102], [201] Consonant   set 9  
U+0DC5 Sinhala SINHALA LETTER MUURDHAJA LAYANNA [102], [201] Consonant      
U+0DC6 Sinhala SINHALA LETTER FAYANNA [102], [201] Consonant      
U+0DCA Sinhala SINHALA SIGN AL-LAKUNA [102], [201] Halant follows-C    
U+0DCF Sinhala SINHALA VOWEL SIGN AELA-PILLA [102], [201] Matra follows-C-or-J    
U+0DD0 Sinhala SINHALA VOWEL SIGN KETTI AEDA-PILLA [102], [201] Matra follows-C-or-J    
U+0DD1 Sinhala SINHALA VOWEL SIGN DIGA AEDA-PILLA [102], [201] Matra follows-C-or-J    
U+0DD2 Sinhala SINHALA VOWEL SIGN KETTI IS-PILLA [102], [201] Matra follows-C-or-J    
U+0DD3 Sinhala SINHALA VOWEL SIGN DIGA IS-PILLA [102], [201] Matra follows-C-or-J    
U+0DD4 Sinhala SINHALA VOWEL SIGN KETTI PAA-PILLA [102], [201] Matra follows-C-or-J    
U+0DD6 Sinhala SINHALA VOWEL SIGN DIGA PAA-PILLA [102], [201] Matra follows-C-or-J    
U+0DD8 Sinhala SINHALA VOWEL SIGN GAETTA-PILLA [102], [201] Matra follows-C-or-J    
U+0DD9 Sinhala SINHALA VOWEL SIGN KOMBUVA [102], [201] Matra follows-C-or-J    
U+0DDA Sinhala SINHALA VOWEL SIGN DIGA KOMBUVA [102], [201] Matra follows-C-or-J    
U+0DDB Sinhala SINHALA VOWEL SIGN KOMBU DEKA [102], [201] Matra follows-C-or-J    
U+0DDC Sinhala SINHALA VOWEL SIGN KOMBUVA HAA AELA-PILLA [102], [201] Matra follows-C-or-J    
U+0DDD Sinhala SINHALA VOWEL SIGN KOMBUVA HAA DIGA AELA-PILLA [102], [201] Matra follows-C-or-J    
U+0DDE Sinhala SINHALA VOWEL SIGN KOMBUVA HAA GAYANUKITTA [102], [201] Matra follows-C-or-J    
U+0DF2 Sinhala SINHALA VOWEL SIGN DIGA GAETTA-PILLA [102], [201] Matra follows-C-or-J    

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.
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 "+".
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.
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.
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.

3 Variant Sets

Summary

Number of variant sets 9
Largest variant set 3
Variants by Type
blocked 22

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.

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 variant sets for each context are disjoint, but code points that have variants with multiple contexts are members of more than one set.

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 variant Type, Ref and Comment apply to the mapping from source to target.
- reverse
Indicates that variant Type, Ref and Comment apply to the reverse mapping from target to source.
- both
Indicates that variant Type, Ref and Comment apply to both forward and reverse mapping.
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.
Required Context
Link to the rule defining a required context the source must satisfy for the variant mapping to be defined. If prefixed by "not:", identifies a context that must not occur.
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 Required Context Ref Comment
0D8D 0D9D 0DD8 ඝෘ blocked not: followed-by-H-or-M    
0D8D 0DC3 0DD8 සෘ blocked not: followed-by-H-or-M    
0D9D 0DD8 ඝෘ 0DC3 0DD8 සෘ blocked not: followed-by-H-or-M    

Variant Set 2 — 2 Members

Source Glyph Target Glyph   Type Required Context Ref Comment
0D91 0DB5 blocked not: followed-by-H-or-M    

Variant Set 3 — 2 Members

Source Glyph Target Glyph   Type Required Context Ref Comment
0D92 0DB5 0DCA ඵ් blocked not: followed-by-B-X-H-or-M    

Variant Set 4 — 2 Members

Source Glyph Target Glyph   Type Required Context Ref Comment
0D93 0DB5 0DD9 ඵෙ blocked not: followed-by-H-or-M    

Variant Set 5 — 2 Members

Source Glyph Target Glyph   Type Ref Comment
0D94 0DB9 blocked    

Variant Set 6 — 2 Members

Source Glyph Target Glyph   Type Ref Comment
0D9B 0DB6 blocked    

Variant Set 7 — 2 Members

Source Glyph Target Glyph   Type Ref Comment
0D9D 0DC3 blocked    

Variant Set 8 — 2 Members

Source Glyph Target Glyph   Type Ref Comment
0DA0 0DC0 blocked    

Variant Set 9 — 2 Members

Source Glyph Target Glyph   Type Ref Comment
0DB7 0DC4 blocked    

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 Tag=Consonant 35 {0D9A-0D9D 0DA0-0DA5 0DA7-0DAB 0DAD-0DB1 0DB4-0DB8 0DBA-0DBB 0DBD 0DC0-0DC6}   Any Sinhala consonant
V Tag=Vowel 15 {0D85-0D8D 0D91-0D96}   Any Sinhala independent vowel
M Tag=Matra 15 {0DCF-0DD4 0DD6 0DD8-0DDE 0DF2}   Any Sinhala vowel sign (matra)
J Tag=Sannjaka 4 {0D9F 0DAC 0DB3 0DB9}   Any Sinhala Sannjaka
H Tag=Halant 1 {0DCA}   The Sinhala Al-Lakuna (Halant)
B Tag=Anusvara 1 {0D82}   The Sinhala Anusvara
X Tag=Visarga 1 {0D83}   The Sinhala Visarga
implicit Tag=sc:Sinh 72 {0D82-0D83 0D85-0D8D 0D91-0D96 0D9A-0D9D 0D9F-0DA5 0DA7-0DB1 0DB3-0DBB 0DBD 0DC0-0DC6 0DCA 0DCF-0DD4 0DD6 0DD8-0DDE 0DF2}   Any character tagged as Sinhala

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.

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
leading-combining-mark (start)[[\p{gc=Mn}]∪[\p{gc=Mc}]]       Default WLE rule matching labels with leading combining marks ⍟
follows-C ([:C:])← ⚓   C   Section 7, WLE 1: Halanta/Virama must be preceded by C
follows-C-or-J ([:C:]|[:J:])← ⚓   C   Section 7, WLE 2: Matra must be preceded by C or J
follows-V-C-or-M ([:V:]|[:C:]|[:M:])← ⚓   C   Section 7, WLE 3: Visarga must be preceded by V, C or M
follows-V-C-J-or-M ([:V:]|[:C:]|[:J:]|[:M:])← ⚓   C   Section 7, WLE 4: Anusvara (Bindu) must be preceded by V, C, J or M
followed-by-H-or-M ⚓ →([:H:]|[:M:])   V   variants are undefined preceding a Halant or Matra
followed-by-B-X-H-or-M ⚓ →([:B:]|[:X:]|[:H:]|[:M:])   V   variants are undefined preceding an Anusvara, Visarga, Halant or Matra

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.
(... | ...) - 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.
[: :] - 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 at least one variant is in {out-of-repertoire-var} invalid   any variant label with a code point out of repertoire is invalid ⍟
3 if at least one variant is in {blocked} blocked   any variant label containing blocked variants is blocked ⍟
4 if each variant is in {allocatable} allocatable   variant labels with all variants allocatable are allocatable ⍟
5 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

[102] Disanayaka, JB. 2006. Sinhala Akshara Vicharaya (Sinhala Graphology), Sumitha Publishers, Kalubovila. ISBN: 955-1146-44-1
[201] Omniglot: The on-line encyclopedia of writing system and Languages, “Sinhala”
https://www.omniglot.com/writing/sinhala.htm