Reference LGR for language: Bulgarian (bg) lgr-second-level-bulgarian-language-18may21-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 2021-05-18
LGR Version 2 (Second Level Reference LGR)
Language bg (Bulgarian Language)
Unicode Version 6.3.0

Table of Contents

1 Description

Label Generation Rules for Bulgarian

Overview

This document specifies a reference set of Label Generation Rules for Bulgarian using a limited repertoire as appropriate for a second level domain.

Repertoire

All references converge on 30 Cyrillic code points (23 +9 as defined by RFC 5992 [130]). CLDR in its auxiliary list adds 7 code points of which 2 correspond to historic letters. These code points are U+0463 (ѣ) CYRILLIC SMALL LETTER YAT and U+046B (ѫ) CYRILLIC SMALL LETTER BIG YUS. They are also excluded from MSR-2 (see MSR-2 in the Table of References) as being obsolete. Of the other 5, 3 have no other sources and are not included. The last 2: U+0450 (ѐ) CYRILLIC SMALL LETTER IE WITH GRAVE and U+045D (ѝ) CYRILLIC SMALL LETTER I WITH GRAVE have additional sources and are part of the extended set.

Note: The article in [605] indicates that "In Bulgarian and Macedonian, the grave accent is sometimes, although not very often, used on the vowels а, о, у, е, и and ъ (ъ exists in Bulgarian only) to mark stress...In a few cases (mostly on the vowels е and и) the stress mark is orthographically required to distinguish words which are Homographs".

There is an IDN table published in the IANA Repository of IDN Practices for Bulgarian by .bg (Bulgaria cctld) in [700]

Excluded code points

Letters documented in some references but not included:

Extended code points

Two letters not considered essential to writing the core vocabulary of the language are nevertheless in common use. Where they have not been added to the core repertoire, they are flagged as "extended-cp" in the table of code points. A context rule is provided that by default will prohibit labels with extended code points. To support extended single code points or code point sequences, delete the context "extended-cp" from their repertoire definition.

Variants

None.

Character Classes

This LGR defines no named character classes.

Rules

Common rules only:

Actions

Actions included are the default actions for LGRs as well as those needed to invalidate labels with misplaced combining marks.

Variant-related actions included to facilitate integration as appropriate.

Methodology and Contributors

This reference LGR for Bulgarian for the 2nd Level has been developed by Michel Suignard and Asmus Freytag, verified in expert reviews by Michael Everson, Nicholas Ostler, and Wil Tan, and based on multiple open public consultations.

Changes from Version 1

Language tag has been updated.

References

General reference for the language:

In the listing of the repertoire by code point, references starting from [0] refer to the version of the Unicode Standard in which the corresponding code point was initially encoded. Other references, (starting from [100]) document usage of code points. For more details, see the Table of References below.

2 Repertoire

Repertoire Summary

Number of elements in repertoire 41
Number of extended elements 2
Total entries in table 43
Number of code points
for each script
Cyrillic 32
Common 11
Longest code point 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 or sequences listed in the following table are not part of the repertoire itself; they document targets for out-of-repertoire variant mappings or optional code points as indicated. See also the legend provided below the table.

Code
Point		 Glyph Script Name Ref Required Context Part of
Repertoire		 Comment
U+002D - Common HYPHEN-MINUS [0] not: hyphen-minus-disallowed ✔  
U+0030 0 Common DIGIT ZERO [0]   ✔  
U+0031 1 Common DIGIT ONE [0]   ✔  
U+0032 2 Common DIGIT TWO [0]   ✔  
U+0033 3 Common DIGIT THREE [0]   ✔  
U+0034 4 Common DIGIT FOUR [0]   ✔  
U+0035 5 Common DIGIT FIVE [0]   ✔  
U+0036 6 Common DIGIT SIX [0]   ✔  
U+0037 7 Common DIGIT SEVEN [0]   ✔  
U+0038 8 Common DIGIT EIGHT [0]   ✔  
U+0039 9 Common DIGIT NINE [0]   ✔  
U+0430 а Cyrillic CYRILLIC SMALL LETTER A [0], [100], [130], [201], [301], [401], [700]   ✔  
U+0431 б Cyrillic CYRILLIC SMALL LETTER BE [0], [100], [130], [201], [301], [401], [700]   ✔  
U+0432 в Cyrillic CYRILLIC SMALL LETTER VE [0], [100], [130], [201], [301], [401], [700]   ✔  
U+0433 г Cyrillic CYRILLIC SMALL LETTER GHE [0], [100], [130], [201], [301], [401], [700]   ✔  
U+0434 д Cyrillic CYRILLIC SMALL LETTER DE [0], [100], [130], [201], [301], [401], [700]   ✔  
U+0435 е Cyrillic CYRILLIC SMALL LETTER IE [0], [100], [130], [201], [301], [401], [700]   ✔  
U+0436 ж Cyrillic CYRILLIC SMALL LETTER ZHE [0], [100], [130], [201], [301], [401], [700]   ✔  
U+0437 з Cyrillic CYRILLIC SMALL LETTER ZE [0], [100], [130], [201], [301], [401], [700]   ✔  
U+0438 и Cyrillic CYRILLIC SMALL LETTER I [0], [100], [130], [201], [301], [401], [700]   ✔  
U+0439 й Cyrillic CYRILLIC SMALL LETTER SHORT I [0], [100], [130], [201], [301], [401], [700]   ✔  
U+043A к Cyrillic CYRILLIC SMALL LETTER KA [0], [100], [130], [201], [301], [401], [700]   ✔  
U+043B л Cyrillic CYRILLIC SMALL LETTER EL [0], [100], [130], [201], [301], [401], [700]   ✔  
U+043C м Cyrillic CYRILLIC SMALL LETTER EM [0], [100], [130], [201], [301], [401], [700]   ✔  
U+043D н Cyrillic CYRILLIC SMALL LETTER EN [0], [100], [130], [201], [301], [401], [700]   ✔  
U+043E о Cyrillic CYRILLIC SMALL LETTER O [0], [100], [130], [201], [301], [401], [700]   ✔  
U+043F п Cyrillic CYRILLIC SMALL LETTER PE [0], [100], [130], [201], [301], [401], [700]   ✔  
U+0440 р Cyrillic CYRILLIC SMALL LETTER ER [0], [100], [130], [201], [301], [401], [700]   ✔  
U+0441 с Cyrillic CYRILLIC SMALL LETTER ES [0], [100], [130], [201], [301], [401], [700]   ✔  
U+0442 т Cyrillic CYRILLIC SMALL LETTER TE [0], [100], [130], [201], [301], [401], [700]   ✔  
U+0443 у Cyrillic CYRILLIC SMALL LETTER U [0], [100], [130], [201], [301], [401], [700]   ✔  
U+0444 ф Cyrillic CYRILLIC SMALL LETTER EF [0], [100], [130], [201], [301], [401], [700]   ✔  
U+0445 х Cyrillic CYRILLIC SMALL LETTER HA [0], [100], [130], [201], [301], [401], [700]   ✔  
U+0446 ц Cyrillic CYRILLIC SMALL LETTER TSE [0], [100], [130], [201], [301], [401], [700]   ✔  
U+0447 ч Cyrillic CYRILLIC SMALL LETTER CHE [0], [100], [130], [201], [301], [401], [700]   ✔  
U+0448 ш Cyrillic CYRILLIC SMALL LETTER SHA [0], [100], [130], [201], [301], [401], [700]   ✔  
U+0449 щ Cyrillic CYRILLIC SMALL LETTER SHCHA [0], [100], [130], [201], [301], [401], [700]   ✔  
U+044A ъ Cyrillic CYRILLIC SMALL LETTER HARD SIGN [0], [100], [130], [201], [301], [401], [700]   ✔  
U+044C ь Cyrillic CYRILLIC SMALL LETTER SOFT SIGN [0], [100], [130], [201], [301], [401], [700]   ✔  
U+044E ю Cyrillic CYRILLIC SMALL LETTER YU [0], [100], [130], [201], [301], [401], [700]   ✔  
U+044F я Cyrillic CYRILLIC SMALL LETTER YA [0], [100], [130], [201], [301], [401], [700]   ✔  
U+0450 ѐ Cyrillic CYRILLIC SMALL LETTER IE WITH GRAVE [3], [301], [402], [605] extended-cp ◯  
U+045D ѝ Cyrillic CYRILLIC SMALL LETTER I WITH GRAVE [3], [301], [402], [605] extended-cp ◯  

Legend

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.
Name
Shows the character or sequence name from the Unicode Character Database.
Ref
Links to the references associated with the code point or sequence, if any.
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.
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.
◯ - 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 removing the relevant context restriction.

3 Variant Sets

This LGR does not specify any variants.

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
implicit Tag=sc:Cyrl 32 {0430-044A 044C 044E-0450 045D}   Any character tagged as Cyrillic
implicit Tag=sc:Zyyy 11 {002D 0030-0039}   Any character tagged as Common

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 and 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
leading-combining-mark (start)[∅=[[∅=\p{gc=Mn}] ∪ [∅=\p{gc=Mc}]]] ✔     [120] RFC5891 restrictions on placement of combining marks
hyphen-minus-disallowed (((start))← ⚓︎)|(⚓︎ →((end)))|(((start)..\u002D)← ⚓︎)   ✔ C [120] RFC5891 restrictions on placement of U+002D (-)
extended-cp (start)(end)     C   code points from the extended range

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.
. - any code point
. matches any code point.
[\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).
∅= - empty set
Indicates that the following set is empty because of the result of set operations, or because none of its elements is part of the repertoire defined here. A rule with a non-optional empty set never matches.
(^$) - empty label
The regex (^$) matches the empty label. Used as a context rule, it always fails to match, thus disallowing the affected code point in any label. By convention, it is used for context rules that disable code points that are not part of the repertoire, yet explicitly listed in the LGR as excluded or for optional future extension.

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   by default, labels with leading combining marks are invalid
2 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.

5 Table of References

The following lists the references cited for specific code points, variants, classes, rules or actions in this LGR.

[0] The Unicode Consortium. The Unicode Standard, Version 6.3.0, (Mountain View, CA: The Unicode Consortium, 2013. ISBN 978-1-936213-08-5)
Any code point cited was originally encoded in Unicode Version 1.1
[3] The Unicode Consortium. The Unicode Standard, Version 6.3.0, (Mountain View, CA: The Unicode Consortium, 2013. ISBN 978-1-936213-08-5)
Any code point cited was originally encoded in Unicode Version 3.0
[100] Internetstiftelsen i Sverige (IIS), Bulgarian
https://github.com/dotse/IDN-ref-tables/blob/master/language-tables/bulgarian-lang-ref-table.txt
[107] MSR-2 Maximum Starting Repertoire
https://www.icann.org/en/system/files/files/msr-2-overview-14apr15-en.pdf
[120] RFC5891, Internationalized Domain Names in Applications (IDNA): Protocol
http://tools.ietf.org/html/rfc5891
[130] RFC5992, Internationalized Domain Names Registration and Administration Guidelines for European Languages Using Cyrillic - section 2.2 Bulgarian
https://tools.ietf.org/html/rfc5992
[201] Omniglot Bulgarian
http://www.omniglot.com/writing/bulgarian.htm
Code points cited form the standard set
[204] Omniglot Bulgarian
http://www.omniglot.com/writing/bulgarian.htm
Code points cited are rare or archaic
[301] Everson, Michael, The Alphabets of Europe, Bulgarian
http://evertype.com/alphabets/bulgarian.pdf
Code points cited form the standard set
[304] Everson, Michael, The Alphabets of Europe, Bulgarian
http://evertype.com/alphabets/bulgarian.pdf
Code points cited are rare or archaic
[401] The Unicode Consortium, Common Locale Data Repository - CLDR Version 28 (2015-09-16) - Locale Data Summary for Bulgarian [bg]-
http://www.unicode.org/cldr/charts/28/summary/bg.html
Code points cited are from the set of Main Letters
[402] The Unicode Consortium, Common Locale Data Repository - CLDR Version 28 (2015-09-16) - Locale Data Summary for Bulgarian [bg]-
http://www.unicode.org/cldr/charts/28/summary/bg.html
Code points cited are from the set of Auxiliary Letters
[605] Wikipedia
https://en.wikipedia.org/wiki/Grave_accent
accessed 2015-11-11
Article providing evidence for the use of the grave accent in Bulgarian and Macedonian
[700] Register.BG (.bg cctld Bulgarian Register)
http://www.iana.org/domains/idn-tables/tables/bg_bg-bg_1.0.html