RDF.LangString.match_language-question-mark

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match_language?(language_tag, language_range)

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Specs

match_language?(RDF.Literal.t() | t() | String.t(), String.t()) :: boolean()

Checks if a language tagged string literal or language tag matches a language range.

The check is performed per the basic filtering scheme defined in RFC4647 section 3.3.1. A language range is a basic language range per Matching of Language Tags in RFC4647 section 2.1. A language range of "*" matches any non-empty language-tag string.

see https://www.w3.org/TR/sparql11-query/#func-langMatches