afs commented on PR #3405: URL: https://github.com/apache/jena/pull/3405#issuecomment-3240031592
Jena 5.4.0 introduced `jena-langtag`. The RDF 1.1 spec says "language tags MAY be converted to lower case. The value space of language tags is always in lower case." This leads to differences across systems (when are we in "value space" for a language tag?) but also differences between Jena dataset implementations. Now RDF 1.2 Concepts says "MUST be treated accordingly, that is, in a case-insensitive manner." Jena went with the algorithm in [RFC 5646 section 2.1.1](https://datatracker.ietf.org/doc/html/rfc5646#section-2.1.1), without regitry access, based on some previous user feedback. Language tag are now parsed or created as case-normalized following RFC 5646 form (lang is lowercase, region is uppercase) then comparison. The original language tag is not preserved. The WG did a survey of systems: it found systems providing lower case and systems providing the algorithm in RFC 5646 section 2.1.1. Jena went with the algorithm in RFC 5646 based on some previous user feedback. There is an [entry in the RDF 1.2 change log](https://www.w3.org/TR/rdf12-concepts/#:~:text=Implementations%20were%20previously%20allowed%20to%20normalize%20language%20tags%20to%20lower%20case%2C). For initial text direction, the strings are `ltr` or `rtl` and lower case is required. CHANGES for jena 5.4.0: > == New artifact > > Jena 5.4.0 introduces a new module jena-langtag for language tag parsing > in compliance with RFC 5646. Language tag validation is strengthened. > When parsing, language tag violations are still treated as warnings. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: pr-unsubscr...@jena.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: pr-unsubscr...@jena.apache.org For additional commands, e-mail: pr-h...@jena.apache.org
