7.3 KiB
bcp-47
Parse and stringify BCP 47 language tags.
Install
npm:
npm install bcp-47
Contents
Use
var bcp47 = require('bcp-47')
var schema = bcp47.parse('hy-Latn-IT-arevela')
console.log(schema)
console.log(bcp47.stringify(schema))
Yields:
{ language: 'hy',
extendedLanguageSubtags: [],
script: 'Latn',
region: 'IT',
variants: ['arevela'],
extensions: [],
privateuse: [],
irregular: null,
regular: null }
'hy-Latn-IT-arevela'
API
bcp47.parse(tag[, options])
Parse a BCP 47 tag into a language schema. Note that the algorithm is case-insensitive.
options.normalize
Whether to normalize legacy tags when possible (boolean
, default:
true
). For example, i-klingon
does not match the BCP 47 language
algorithm but is valid nonetheless. It is suggested to use tlh
instead (the ISO 639-3 code for Klingon). When normalize
is true,
passing i-klingon
, or other deprecated tags, is handled as if their
suggested valid tag was given.
options.forgiving
By default, when an error is encountered, an empty object is returned.
When in forgiving mode, all found values up to the point of the error
are included (boolean
, default: false
). So, for example, where by
default en-GB-abcdefghi
an empty object is returned (as the language
variant is too long), in forgiving
mode the language
of schema
is
populated with en
and the region
is populated with GB
.
options.warning
When given, warning
is invoked when an error is encountered
(Function
).
Returns
Schema
— Parsed BCP 47 language tag.
Throws
When tag
is null
or undefined
.
bcp47.stringify(schema)
Compile a schema
into a BCP 47 language tag.
Returns
string
— BCP 47 language tag.
schema
A schema may have the following properties. A schema is deemed empty
when it has neither language
, irregular
, regular
, nor privateuse
(where an empty privateuse
array is handled as no privateuse
, too).
schema.language
Two or three character ISO 639 language code, four character
reserved language code, or 5 to 8 (inclusive) characters registered
language subtag (string
). For example, en
(English) or cmn
(Mandarin Chinese).
schema.extendedLanguageSubtags
Selected three-character ISO 639 codes(Array.<string>
),
such as yue
in zh-yue-HK
(Chinese, Cantonese, as used in Hong Kong
SAR).
schema.script
Four character ISO 15924 script code (string
), such as
Latn
in hy-Latn-IT-arevela
(Eastern Armenian written in Latin
script, as used in Italy).
schema.region
Two alphabetical character ISO 3166-1 code, or three
digit UN M.49 code (string
). For example, CN
in
cmn-Hans-CN
(Mandarin Chinese, Simplified script, as used in China).
schema.variants
5 to 8 (inclusive) character language variants (Array.<string>
), such
as both rozaj
and biske
in sl-rozaj-biske
(San Giorgio dialect
of Resian dialect of Slovenian).
schema.extensions
List of extensions (Array.<Object>
), each an object containing a one
character singleton
, and a list of extensions
(string
).
singleton
cannot be x
(case-insensitive), and extensions
must be
between two and eight (inclusive) characters. For example, an extension
would be u-co-phonebk
in de-DE-u-co-phonebk
(German, as used in
Germany, using German phonebook sort order), where u
is the singleton
and co
and phonebk
are its extensions.
schema.privateuse
List of private-use subtags (Array.<string>
), where each subtag must
be between one and eight (inclusive) characters.
schema.regular
One of the regular
tags (string
): tags which are seen as something
different by the algorithm.
Valid values are:
art-lojban
cel-gaulish
no-bok
no-nyn
zh-guoyu
zh-hakka
zh-min
zh-min-nan
zh-xiang
schema.irregular
One of the irregular
tags (string
): tags which are seen as
invalid by the algorithm).
Valid values are:
en-GB-oed
i-ami
i-bnn
i-default
i-enochian
i-hak
i-klingon
i-lux
i-mingo
i-navajo
i-pwn
i-tao
i-tay
i-tsu
sgn-BE-FR
sgn-BE-NL
sgn-CH-DE
function warning(reason, code, offset)
Invoked when an error occurs.
Parameters
reason
(string
) — English reason for failurecode
(number
) — Code for failureoffset
(number
) — Index-based position of error
Warnings
code | reason |
---|---|
1 | Too long variant, expected at most 8 characters |
2 | Too long extension, expected at most 8 characters |
3 | Too many extended language subtags, expected at most 3 subtags |
4 | Empty extension, extensions must have at least 2 characters of content |
5 | Too long private-use area, expected at most 8 characters |
6 | Found superfluous content after tag |
Related
bcp-47-match
— Match BCP 47 language tags with language ranges per RFC 4647bcp-47-normalize
— Normalize, canonicalize, and format BCP 47 tagsiso-3166
— ISO 3166 codesiso-639-2
— ISO 639-2 codesiso-639-3
— ISO 639-3 codesiso-15924
— ISO 15924 codesun-m49
— UN M49 codes