Label Generation Rules for Norwegian

Overview

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

Repertoire

Most references converge on 43 (36+7) Latin code points with a few additional extensions.

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

Norwegian is not a single language. Instead, there are two closely related but different written languages (Bokmål and Nynorsk). As both of them are written in the same country and the differences are relatively minor for purposes of IDNs, this LGR covers both, by extending the repertoire slightly.

Excluded code points

Letters documented in some references but not included:

• U+00E2 (â) LATIN SMALL LETTER A WITH CIRCUMFLEX

• U+00EF (ï) LATIN SMALL LETTER I WITH DIAERESIS

• U+00F9 (ù) LATIN SMALL LETTER U WITH GRAVE

• U+00FB (û) LATIN SMALL LETTER U WITH CIRCUMFLEX

• U+01CE (ǎ) LATIN SMALL LETTER A WITH CARON

Extended code points

A number of 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 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.

The following extended code points in particular are needed to write Northern Sami, a minority language in Norway.

• U+010D (č) LATIN SMALL LETTER C WITH CARON

• U+0111 (đ) LATIN SMALL LETTER D WITH STROKE

• U+0144 (ń) LATIN SMALL LETTER N WITH ACUTE ACCENT (alternate for N with tilde in Lule Sami)

• U+014B (ŋ) LATIN SMALL LETTER ENG

• U+0161 (š) LATIN SMALL LETTER S WITH CARON

• U+0167 (ŧ) LATIN SMALL LETTER T WITH STROKE

• U+017E (ž) LATIN SMALL LETTER Z WITH CARON

Variants

None.

Character Classes

This LGR defines no named character classes.

Rules

Common rules only:

• Hyphen Restrictions — restrictions on the allowable placement of hyphens (no leading/ending hyphen and no hyphen in positions 3 and 4). These restrictions are described in section 4.2.3.1 of RFC5891 [120]. They are implemented here as context rule on U+002D (-) (-) HYPHEN-MINUS.

• Leading Combining Marks — restrictions on the allowable placement of combining marks (no leading combining mark). This rule is described in section 4.2.3.2 of RFC5891 [120].

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 Norwegian 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.

References

General references for the language:

• Norsk språkråd, in Icelandic Council for Standardization. 1992. Nordic cultural requirements on information technology. Reykjavík: Staðlaráð Íslands. ISBN 9979-9004-3-1

• Hovdenak, Marit, et al. 1994. Nynorskordboka: definisjons- og rettskrivings- ordbok. Oslo: Det norske samlaget. ISBN 82-521-4121-8- The repertoire covers Bokmål and Nynorsk

• Wikipedia: "Norwegian orthography",
  http://en.wikipedia.org/wiki/Norwegian_alphabet

• Omniglot: "Norwegian (norsk)"
  http://www.omniglot.com/writing/norwegian.htm

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.

Character Classes

The following table lists all named 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	53 Elements:	{0061-007A 00E0-00E1 00E3-00EB 00ED 00F1-00F4 00F6 00F8 00FA 00FC 010D 0111 0144 014B 0161 0167 ...}
implicit	Tag=sc:Zyyy	11 Elements:	{002D 0030-0039}

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. (Any use of context rules for variants is not indicated).

Name	Used as Trigger	Used as Context	Anchor	Regular Expression	Ref	Comment
leading-combining-mark	✔			(^[∅=[[∅=\p{gc=Mn}][∅=\p{gc=Mc}]]])	[120]	RFC5891 restrictions on placement of combining marks
hyphen-minus-disallowed		✔	✔	((((?<=^)⚓)|(⚓(?=$))|((?<=^..\u002D)⚓)))	[120]	RFC5891 restrictions on placement of U+002D
extended-cp		✔		(^$)		code points from the extended range

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