- From: Hans-Juergen Rennau <hrennau@yahoo.de>
- Date: Tue, 28 Aug 2018 22:51:28 +0000 (UTC)
- To: "public-rdf-dawg-comments@w3.org" <public-rdf-dawg-comments@w3.org>
- Message-ID: <957538762.6285356.1535496688920@mail.yahoo.com>
The section specifies RDFterm-equal in an inconsistent way. Quote:=========================================================== term1 and term2 are the same if any of the following is true:...term1 and term2 are equivalent literals as defined in 6.5.1 Literal Equality of [CONCEPTS].... =========================================================== Following the link to "6.5.1 Literal Equality" one finds: =========================================================== 6.5.1 Literal Equality Two literals are equal if and only if all of the following hold: - The strings of the two lexical forms compare equal, character by character. - Either both or neither have language tags. - The language tags, if any, compare equal. - Either both or neither have datatype URIs. - The two datatype URIs, if any, compare equal, character by character. ...=========================================================== Note that the text does not define "equivalent literals", but literal equality, and this equality is described as syntactic equality. However, the section includes an example in which RDFterm-equal returns true in the case of value equality without literal equality:"2004-12-31T19:00:00-05:00"^^<http://www.w3.org/2001/XMLSchema#dateTime> xsd:dateTime("2005-01-01T00:00:00Z")A footnote following the example confirms the use of value equality, opposed to syntactic equality:"Invoking RDFterm-equal on two typed literals tests for equivalent values." Conclusion: the specification of RDFterm-equal is inconsistent, describing it in one place to mean literal equality and in another place to mean value equality. Additional problem: the sentence from the beginning of the section: "produces a type error if the arguments are both literal but are not the same RDF term *;" is quite confusing - (a) what is the meaning of the hyphen preceding the semicolon?(b) why should two literals which are not the same RDF term produce a type error, if a boolean assessment of equality is expected(c) the statement is contradicted by both examples where arguments which are literals without equality do not produce a type error. Hans-Juergen Rennau
Received on Tuesday, 28 August 2018 22:52:13 UTC