LGR for urd-Arab

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.

LGR Version 1
Date 2017-04-26
Unicode Version 6.3.0
Language urd-Arab

Description

Label Generation Rules for Urdu

Overview

This document specifies a reference set of Label Generation Rules for Urdu using a limited repertoire as appropriate for a second level domain. This is a DRAFT document for public comments released by the Task Force for Arabic Script IDNs - TF-AIDN.

Repertoire

The repertoire consist of the 39 letters of the Urdu alphabet, two sets of digits and the hyphen. The code point U+0626 (ئ) is only allowed when in intiail or medial position.

Variants

Blocked variants

The following pairs of code points are blocked variants: U+0646 (ن) / U+06BA (ں) and U+06C1 (ہ) / U+06BE (ھ).

Allocatable variants

Corresponding members of the two sets of digits (ASCII digits and Exented Arabic Indic digits) are allocatable variants of each other

Out-of-repertoire Variants

Script-level Variants

This LGR does not include any script level variants. In case this LGR is integrated with other LGRs using Arabic script, the variant sets defined in the Root Zone LGR (see https://www.icann.org/sites/default/files/lgr/lgr-1-arabic-script-24feb16-en.html) should be considered.

Rules

Repertoire

Summary

Number of elements in Repertoire 61
Number of extended elements 0
Number of excluded elements 0
Total entries in table 61
Number of code point sequences 0

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 the 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, the link to the associated variant set, or if mapped to itself, the variant type of that mapping is provided in the Variants column.

# Code
Point		 Glyph Script Name Tags Required Context Part of
Repertoire		 Variants Comment References
1 002D - Common HYPHEN-MINUS     ✔    
2 0030 0 Common DIGIT ZERO ASCII-digit   ✔ set 1    
3 0031 1 Common DIGIT ONE ASCII-digit   ✔ set 2    
4 0032 2 Common DIGIT TWO ASCII-digit   ✔ set 3    
5 0033 3 Common DIGIT THREE ASCII-digit   ✔ set 4    
6 0034 4 Common DIGIT FOUR ASCII-digit   ✔ set 5    
7 0035 5 Common DIGIT FIVE ASCII-digit   ✔ set 6    
8 0036 6 Common DIGIT SIX ASCII-digit   ✔ set 7    
9 0037 7 Common DIGIT SEVEN ASCII-digit   ✔ set 8    
10 0038 8 Common DIGIT EIGHT ASCII-digit   ✔ set 9    
11 0039 9 Common DIGIT NINE ASCII-digit   ✔ set 10    
12 0621 ء Arabic ARABIC LETTER HAMZA     ✔    
13 0622 آ Arabic ARABIC LETTER ALEF WITH MADDA ABOVE     ✔    
14 0626 ئ Arabic ARABIC LETTER YEH WITH HAMZA ABOVE   precedes-right-joining  ✔    
15 0627 ا Arabic ARABIC LETTER ALEF     ✔    
16 0628 ب Arabic ARABIC LETTER BEH     ✔    
17 062A ت Arabic ARABIC LETTER TEH     ✔    
18 062B ث Arabic ARABIC LETTER THEH     ✔    
19 062C ج Arabic ARABIC LETTER JEEM     ✔    
20 062D ح Arabic ARABIC LETTER HAH     ✔    
21 062E خ Arabic ARABIC LETTER KHAH     ✔    
22 062F د Arabic ARABIC LETTER DAL     ✔    
23 0630 ذ Arabic ARABIC LETTER THAL     ✔    
24 0631 ر Arabic ARABIC LETTER REH     ✔    
25 0632 ز Arabic ARABIC LETTER ZAIN     ✔    
26 0633 س Arabic ARABIC LETTER SEEN     ✔    
27 0634 ش Arabic ARABIC LETTER SHEEN     ✔    
28 0635 ص Arabic ARABIC LETTER SAD     ✔    
29 0636 ض Arabic ARABIC LETTER DAD     ✔    
30 0637 ط Arabic ARABIC LETTER TAH     ✔    
31 0638 ظ Arabic ARABIC LETTER ZAH     ✔    
32 0639 ع Arabic ARABIC LETTER AIN     ✔    
33 063A غ Arabic ARABIC LETTER GHAIN     ✔    
34 0641 ف Arabic ARABIC LETTER FEH     ✔    
35 0642 ق Arabic ARABIC LETTER QAF     ✔    
36 0644 ل Arabic ARABIC LETTER LAM     ✔    
37 0645 م Arabic ARABIC LETTER MEEM     ✔    
38 0646 ن Arabic ARABIC LETTER NOON     ✔ set 11    
39 0648 و Arabic ARABIC LETTER WAW     ✔    
40 067E پ Arabic ARABIC LETTER PEH     ✔    
41 0686 چ Arabic ARABIC LETTER TCHEH     ✔    
42 0688 ڈ Arabic ARABIC LETTER DDAL     ✔    
43 0691 ڑ Arabic ARABIC LETTER RREH     ✔    
44 0698 ژ Arabic ARABIC LETTER JEH     ✔    
45 06A9 ک Arabic ARABIC LETTER KEHEH     ✔    
46 06AF گ Arabic ARABIC LETTER GAF     ✔    
47 06BA ں Arabic ARABIC LETTER NOON GHUNNA     ✔ set 11    
48 06BE ھ Arabic ARABIC LETTER HEH DOACHASHMEE     ✔ set 12    
49 06C1 ہ Arabic ARABIC LETTER HEH GOAL     ✔ set 12    
50 06CC ی Arabic ARABIC LETTER FARSI YEH     ✔    
51 06D2 ے Arabic ARABIC LETTER YEH BARREE     ✔    
52 06F0 ۰ Arabic EXTENDED ARABIC-INDIC DIGIT ZERO extended-arabic-indic-digit   ✔ set 1    
53 06F1 ۱ Arabic EXTENDED ARABIC-INDIC DIGIT ONE extended-arabic-indic-digit   ✔ set 2    
54 06F2 ۲ Arabic EXTENDED ARABIC-INDIC DIGIT TWO extended-arabic-indic-digit   ✔ set 3    
55 06F3 ۳ Arabic EXTENDED ARABIC-INDIC DIGIT THREE extended-arabic-indic-digit   ✔ set 4    
56 06F4 ۴ Arabic EXTENDED ARABIC-INDIC DIGIT FOUR extended-arabic-indic-digit   ✔ set 5    
57 06F5 ۵ Arabic EXTENDED ARABIC-INDIC DIGIT FIVE extended-arabic-indic-digit   ✔ set 6    
58 06F6 ۶ Arabic EXTENDED ARABIC-INDIC DIGIT SIX extended-arabic-indic-digit   ✔ set 7    
59 06F7 ۷ Arabic EXTENDED ARABIC-INDIC DIGIT SEVEN extended-arabic-indic-digit   ✔ set 8    
60 06F8 ۸ Arabic EXTENDED ARABIC-INDIC DIGIT EIGHT extended-arabic-indic-digit   ✔ set 9    
61 06F9 ۹ Arabic EXTENDED ARABIC-INDIC DIGIT NINE extended-arabic-indic-digit   ✔ set 10    

Legend

Code Point
A code point or code point sequence.
Name
Shows the character or sequence name from the Unicode Character Database.
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.
References
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 the rule defining the required context a code point or sequence must satisfy. If prefixed by "not:", identifies a context that must not occur.
Variants
A 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
If the comment in this row consists only of the code point or sequence name it is suppressed in this view.
✔ - core repertoire
A check mark in the Part-of-Repertoire column indicates a code point is part of the core repertoire.
◯ - extended repertoire
An open circle indicates a code point is part of an optional extended repertoire, which is normally disabled but could be supported by deleting the relevant context restriction.
✗ - excluded from repertoire
A code point shown with ✗ is considered excluded from the repertoire. It is shown only for review purposes.

Variant Sets

Summary

Number of variant sets 12
Largest variant set 2
Ordinary Variants by Type allocatable (20)
blocked (4)
Reflexive Variants by Type  

The following tables list each pair of variant mappings on one row. For each pair of code points, by convention, the lower code point is taken as the source of the mapping in the forward → direction and the reverse direction ← is not listed separately. The variant mappings defined in an LGR are required to be symmetric, that is, both the forward and reverse mappings must be specified.

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 “≡”.

Where the type of both forward and reverse mappings are the same, a single value is given in the Type(s) column, otherwise the types for forward and reverse mapping are given in that order, as indicated by the arrows. The same applies to any comments.

In a properly specified LGR, all members of each variant set are variants of each other, a property called transitivity. Because of that, all variant sets are necessarily disjoint. In each set, shading is used to group mappings from the same source code point or sequence.

Variant Set 1 — 2 Members

# Source Glyph Target Glyph   Type(s) Ref Comment
1 0030 0 06F0 ۰ ↔ allocatable    

Variant Set 2 — 2 Members

# Source Glyph Target Glyph   Type(s) Ref Comment
1 0031 1 06F1 ۱ ↔ allocatable    

Variant Set 3 — 2 Members

# Source Glyph Target Glyph   Type(s) Ref Comment
1 0032 2 06F2 ۲ ↔ allocatable    

Variant Set 4 — 2 Members

# Source Glyph Target Glyph   Type(s) Ref Comment
1 0033 3 06F3 ۳ ↔ allocatable    

Variant Set 5 — 2 Members

# Source Glyph Target Glyph   Type(s) Ref Comment
1 0034 4 06F4 ۴ ↔ allocatable    

Variant Set 6 — 2 Members

# Source Glyph Target Glyph   Type(s) Ref Comment
1 0035 5 06F5 ۵ ↔ allocatable    

Variant Set 7 — 2 Members

# Source Glyph Target Glyph   Type(s) Ref Comment
1 0036 6 06F6 ۶ ↔ allocatable    

Variant Set 8 — 2 Members

# Source Glyph Target Glyph   Type(s) Ref Comment
1 0037 7 06F7 ۷ ↔ allocatable    

Variant Set 9 — 2 Members

# Source Glyph Target Glyph   Type(s) Ref Comment
1 0038 8 06F8 ۸ ↔ allocatable    

Variant Set 10 — 2 Members

# Source Glyph Target Glyph   Type(s) Ref Comment
1 0039 9 06F9 ۹ ↔ allocatable    

Variant Set 11 — 2 Members

# Source Glyph Target Glyph   Type(s) Ref Comment
1 0646 ن 06BA ں ↔ blocked    

Variant Set 12 — 2 Members

# Source Glyph Target Glyph   Type(s) Ref Comment
1 06BE ھ 06C1 ہ ↔ blocked    

Classes, Rules and Actions

Character Classes

The following table lists all top-level classes with their definition and a list of their members intersected with the current repertoire.

Name Definition Count Members Comment
implicit Tag=ASCII-digit 10 Elements { 0030 0031 0032 0033 0034 0035 0036 0037 0038 0039 }  
implicit Tag=extended-arabic-indic-digit 10 Elements { 06F0 06F1 06F2 06F3 06F4 06F5 06F6 06F7 06F8 06F9 }  

Legend

Members
Lists the members of the class as code points (xxx). Any class too numerous to list in full is linked with "..." to all the members.
Tag=ttt
A named class is defined by all code points that share the given tag value (ttt).
Implicit
An anonymous class implicitly defined class based on tag value.

Whole label evaluation and context rules

The following table lists all the top-level, or 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. (Any use of context rules for variants is not indicated).

Name Regular Expression Used as
Trigger		 Used as
Context		 Anchor Ref Comment
leading-combining-mark (start)((class property:gc:Mn) | (class property:gc:Mc)) ✔     [120] RFC5891 restrictions on placement of combining marks
mixed-digits (choice [(ASCII-digit)(0+ any)(extended-arabic-indic-digit)][(extended-arabic-indic-digit)(0+ any)(ASCII-digit)]) ✔       Labels with a mix of European and Extended-Arabic-Indic digits are invalid
precedes-right-joining (anchor)(((class property:jt:D) | (class property:jt:R)))   ✔ ✔   must precede a code point joining on the right

Legend

Regular Expression
A regular expression equivalent to the rule, shown in the standard notation with some extensions as noted.
[] - a choice
When there are various choices in a rule, each choice is represented by a set enclosed in square brackets.
[∩,−,Δ,∪] - set operators
Sets may be combined by set operators (∩ = intersection, − = difference, Δ = symmetric difference and ∪ = union).
()= - empty set
Indicates that the following set is empty because of the result of set operations, or because none of its elements are part of the repertoire defined here.An empty set that is not optional means that a rule can never match.

Note: The terminologies used in the regular expressions are followed from RFC7940.

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   by default, labels with leading combining marks are invalid
2 if label matches mixed-digits → invalid   RTL labels with a mix of European and Arabic-Indic digits are invalid
3 if at least one variant is in {out-of-repertoire-var} → invalid   disallow code points that are out of repertoire
4 if at least one variant is in {similar} → blocked   default action for similarity variants
5 if at least one variant is in {blocked} → blocked   default action for blocked variants
6 if at least one variant is in {allocatable} → allocatable   default action for allocatable variants
7 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.

Table of References

[120] RFC5891, Internationalized Domain Names in Applications (IDNA): Protocol http://tools.ietf.org/html/rfc5891
None