Reference LGR for language: Danish (da) lgr-second-level-danish-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 da (Danish Language)
Unicode Version 6.3.0

Table of Contents

1 Description

Label Generation Rules for Danish

Overview

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

Repertoire

Most references converge on 31 (29+2) Latin code points. In addition to the 29 letters of the alphabet proper, these include two letter used as part of the proper spelling of certain words: U+00E9 (é) LATIN SMALL LETTER E WITH ACUTE and U+00FC (ü) LATIN SMALL LETTER U WITH DIAERESIS. Both occur in spelling dictionaries and especially the former is used in many ordinary words. The repertoire here adds U+00E4 (ä) LATIN SMALL LETTER A WITH DIAERESIS and U+00F6 (ö) LATIN SMALL LETTER O WITH DIAERESIS, both of which are used in neighboring Sweden and Germany. Finally, the use of all three code points with diaresis, alone or together with code points from the core Danish alphabet such as U+00F8 (ø) LATIN SMALL LETTER O WITH STROKE is not uncommon in family names. All three are available on Danish keyboards.

There is no IDN table published in the IANA Repository of IDN Practices by .dk ccTLD, but the registry provides IDN information [700].

Excluded code points

Letters documented in some references but not included:

The above list includes code points for languages like Faroese, which are written in territories associated with the country of Denmark, but that are not part of the Danish language.

Extended code points

None.

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.

Methodology and Contributors

This reference LGR for Danish 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 references 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 44
Number of code points
for each script
Latin 33
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.

See also the legend provided below the table.

Code
Point
Glyph Script Name Ref Required Context Comment
U+002D - Common HYPHEN-MINUS [0], [100], [301], [401], [501], [601] not: hyphen-minus-disallowed  
U+0030 0 Common DIGIT ZERO [0], [100], [301], [401], [501], [601]    
U+0031 1 Common DIGIT ONE [0], [100], [301], [401], [501], [601]    
U+0032 2 Common DIGIT TWO [0], [100], [301], [401], [501], [601]    
U+0033 3 Common DIGIT THREE [0], [100], [301], [401], [501], [601]    
U+0034 4 Common DIGIT FOUR [0], [100], [301], [401], [501], [601]    
U+0035 5 Common DIGIT FIVE [0], [100], [301], [401], [501], [601]    
U+0036 6 Common DIGIT SIX [0], [100], [301], [401], [501], [601]    
U+0037 7 Common DIGIT SEVEN [0], [100], [301], [401], [501], [601]    
U+0038 8 Common DIGIT EIGHT [0], [100], [301], [401], [501], [601]    
U+0039 9 Common DIGIT NINE [0], [100], [301], [401], [501], [601]    
U+0061 a Latin LATIN SMALL LETTER A [0], [100], [301], [401], [501], [601]    
U+0062 b Latin LATIN SMALL LETTER B [0], [100], [301], [401], [501], [601]    
U+0063 c Latin LATIN SMALL LETTER C [0], [100], [301], [401], [501], [601]    
U+0064 d Latin LATIN SMALL LETTER D [0], [100], [301], [401], [501], [601]    
U+0065 e Latin LATIN SMALL LETTER E [0], [100], [301], [401], [501], [601]    
U+0066 f Latin LATIN SMALL LETTER F [0], [100], [301], [401], [501], [601]    
U+0067 g Latin LATIN SMALL LETTER G [0], [100], [301], [401], [501], [601]    
U+0068 h Latin LATIN SMALL LETTER H [0], [100], [301], [401], [501], [601]    
U+0069 i Latin LATIN SMALL LETTER I [0], [100], [301], [401], [501], [601]    
U+006A j Latin LATIN SMALL LETTER J [0], [100], [301], [401], [501], [601]    
U+006B k Latin LATIN SMALL LETTER K [0], [100], [301], [401], [501], [601]    
U+006C l Latin LATIN SMALL LETTER L [0], [100], [301], [401], [501], [601]    
U+006D m Latin LATIN SMALL LETTER M [0], [100], [301], [401], [501], [601]    
U+006E n Latin LATIN SMALL LETTER N [0], [100], [301], [401], [501], [601]    
U+006F o Latin LATIN SMALL LETTER O [0], [100], [301], [401], [501], [601]    
U+0070 p Latin LATIN SMALL LETTER P [0], [100], [301], [401], [501], [601]    
U+0071 q Latin LATIN SMALL LETTER Q [0], [100], [301], [401], [502], [601]    
U+0072 r Latin LATIN SMALL LETTER R [0], [100], [301], [401], [501], [601]    
U+0073 s Latin LATIN SMALL LETTER S [0], [100], [301], [401], [501], [601]    
U+0074 t Latin LATIN SMALL LETTER T [0], [100], [301], [401], [501], [601]    
U+0075 u Latin LATIN SMALL LETTER U [0], [100], [301], [401], [501], [601]    
U+0076 v Latin LATIN SMALL LETTER V [0], [100], [301], [401], [501], [601]    
U+0077 w Latin LATIN SMALL LETTER W [0], [100], [301], [401], [501], [601]    
U+0078 x Latin LATIN SMALL LETTER X [0], [100], [301], [401], [501], [601]    
U+0079 y Latin LATIN SMALL LETTER Y [0], [100], [301], [401], [502], [601]    
U+007A z Latin LATIN SMALL LETTER Z [0], [100], [301], [401], [501], [601]    
U+00E4 ä Latin LATIN SMALL LETTER A WITH DIAERESIS [0], [402], [503], [700]    
U+00E5 å Latin LATIN SMALL LETTER A WITH RING ABOVE [0], [100], [200], [301], [401], [501], [603], [604], [700]    
U+00E6 æ Latin LATIN SMALL LETTER AE [0], [100], [200], [401], [501], [603], [604], [700]    
U+00E9 é Latin LATIN SMALL LETTER E WITH ACUTE [0], [100], [200], [301], [402], [502], [700]    
U+00F6 ö Latin LATIN SMALL LETTER O WITH DIAERESIS [0], [302], [402], [503], [700]    
U+00F8 ø Latin LATIN SMALL LETTER O WITH STROKE [0], [100], [200], [401], [501], [603], [604], [700]    
U+00FC ü Latin LATIN SMALL LETTER U WITH DIAERESIS [0], [100], [302], [402], [503], [700]    

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.

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:Latn 33 {0061-007A 00E4-00E6 00E9 00F6 00F8 00FC}   Any character tagged as Latin
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)         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.

Note: The following rules are defined but not used in this LGR: extended-cp.

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

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)
http://www.unicode.org/versions/Unicode6.3.0/
Code points cited were originally encoded in Unicode Version 1.1
[100] Internetstiftelsen i Sverige (IIS), "IDN Reference table for Danish language"
https://github.com/dotse/IDN-ref-tables/blob/master/language-tables/danish-lang-ref-table.txt
[120] RFC5891, Internationalized Domain Names in Applications (IDNA): Protocol
http://tools.ietf.org/html/rfc5891
[200] ISO/IEC 6937 Third Ed. 2001-12-17- Information technology — Coded graphic character set for text communication — Latin alphabet: Table D.1 (p 35) Use of Latin alphabetic characters.
This table lists only the characters outside the set a-z
[301] Everson, Michael. The Alphabets of Europe: "Danish"
http://www.evertype.com/alphabets/danish.pdf
Code points cited form the standard set
[302] Everson, Michael. The Alphabets of Europe: "Danish"
http://www.evertype.com/alphabets/danish.pdf
Code points cited are from an extended set
[304] Everson, Michael. The Alphabets of Europe: "Danish"
http://www.evertype.com/alphabets/danish.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 Danish [da]
http://www.unicode.org/cldr/charts/28/summary/da.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 Danish [da]
http://www.unicode.org/cldr/charts/28/summary/da.html
Code points cited are from the Auxiliary set
[501] Dansk sprognævn, in Icelandic Council for Standardization. 1992. Nordic cultural requirements on information technology. Reykjavík: Staðlaráð Íslands. ISBN 9979-9004-3-1
Code points cited are of category 1: Letters essential for the language
[502] Dansk sprognævn, in Icelandic Council for Standardization. 1992. Nordic cultural requirements on information technology. Reykjavík: Staðlaráð Íslands. ISBN 9979-9004-3-1
Code points cited are of category 2: Letters commonly used, but not essential
[503] Dansk sprognævn, in Icelandic Council for Standardization. 1992. Nordic cultural requirements on information technology. Reykjavík: Staðlaráð Íslands. ISBN 9979-9004-3-1
Code points cited are of category 3: Letters used for names, in common practice
[504] Dansk sprognævn, in Icelandic Council for Standardization. 1992. Nordic cultural requirements on information technology. Reykjavík: Staðlaráð Íslands. ISBN 9979-9004-3-1
Code points cited are of category 4: Letters that are rarely used
[601] Wikipedia: "Latin Alphabets"
https://en.wikipedia.org/wiki/Latin_alphabets
accessed 2015-10-31
According to this reference, the alphabet is listed as using the full basic set A-Z
[603] ISO/IEC 646:1991 — Information technology — ISO 7-bit coded character set for information interchange
Code points cited are supported in a national edition of ISO-646.
[604] Wikipedia: "Latin Alphabets"
https://en.wikipedia.org/wiki/Latin_alphabets.
accessed 2015-10-31
The table only lists code points beyond A-Z
[700] DK Hostmaster A/S "Tegnsæt for domænenavne"
https://www.dk-hostmaster.dk/find-dk-domaenenavn/tegnsaet-for-domaenenavne/
Code points cited are the non-ASCII code points listed by the registry for .dk domain