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Re: For RDF Concepts: term-equality and value-equality.

From: Pat Hayes <phayes@ihmc.us>
Date: Wed, 8 May 2013 09:12:13 -0500
Cc: RDF-WG <public-rdf-wg@w3.org>
Message-Id: <9EB75144-91BF-40EC-9056-E31E8500D383@ihmc.us>
To: Andy Seaborne <andy.seaborne@epimorphics.com>

On May 7, 2013, at 4:13 AM, Andy Seaborne wrote:

> RDF Concepts says:
> 
> [[
> 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.
> ]]
> 
> I think it would be useful to spell out "term equality" and "value equality" as important concepts.
> 

Blech. I strongly dislike having "kinds" of equality. Equality has one meaning, and it does not admit of degrees or kinds. This is a difference between literals and literal values, not two kinds of equality. We already draw out the distinction between literals and literal values. 

> RDF Concepts already defines "RDF term".
> 
> [[
> Literal term equality: Two literals are term-equals (the same RDF literal) if and only if the two lexical forms, the two datatype IRIs, and the two language tags (if any) compare equal, character by character.
> ]]
> 
> [[
> Literal value equality: Two literals that are associated with the same value as said to be value-equals.
> 
> Two literals can be value-equals without being the same term.  For example:
> 
> "1"^^xs:integer
> 
> "01"^^xs:integer
> 
> are assciated with the same value, but are not the same literal RDF terms and are not term-equals.
> ]]
> 
> ("associated" is the work used in 5.5 currently)

Why not say "refer to" or "denotes", both of which are used throughout the spec? Why introduce another terminology?

Pat

> 
> 	Andy
> 
> 

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Received on Wednesday, 8 May 2013 14:12:55 UTC

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