Equality of rdf:langString

BCP47 does not require a fixed case for lamnguage tags; it talks about 
equivalence.  We should do the same.

Proposal:

Two literals of rdf:langString are considered equal if they have the 
same lexical form and have equivalent language tags by BCP47.

Change to RDF Semantics:

[[
The value space of rdf:langString is the set of all pairs of a string 
with a language tag.
]]
==>
[[
The value space of rdf:langString is the set of all pairs of a string 
with a language tag converted to lower case (US-ASCII).
]]

Change to RDF Concepts:

[[
a non-empty language tag as defined by [BCP47]. The language tag must be 
well-formed according to section 2.2.9 of [BCP47], and must be 
normalized to lowercase.
]]
==>
[[
a non-empty language tag as defined by [BCP47]. The language tag must be 
well-formed according to section 2.2.9 of [BCP47].
]]

The section on literal term equality remains unchanged:
[[
Literal equality: Two literals are equal if and only if the two lexical 
forms, the two datatype IRIs, and the two language tags (if any) compare 
equal, character by character.
]]

 Andy

Received on Tuesday, 7 May 2013 09:12:54 UTC