Module language

BCP 47 language tags and RFC 4647 basic language ranges.

Language Tags

Confirm that a value carries a well-formed language tag before handing it to an API that expects one:

import { isTag } from "@metreeca/core/language";

if (isTag(value)) {
  // value is typed as Tag
}
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Basic Language Ranges

Confirm in the same way that a value carries a well-formed basic language range, wildcard included:

import { isTagRange } from "@metreeca/core/language";

if (isTagRange(value)) {
  // value is typed as TagRange
}
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Matching

Select the content whose language answers a request, testing a tag against the ranges a client accepts:

import { matchTag } from "@metreeca/core/language";

matchTag("de-CH", "de");  // true - Swiss German matches German range
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Naming

Present a tag to readers as the name of the language it identifies, in a language they understand:

import { nameTag } from "@metreeca/core/language";

nameTag("zh-Hans");        // "Simplified Chinese" - named in English by default
nameTag("zh-Hans", "it");  // "cinese semplificato" - named in Italian
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