- From: Yosi Scharf <syosi@MIT.EDU>
- Date: Thu, 14 Feb 2008 11:13:12 -0500
- To: "Booth, David (HP Software - Boston)" <dbooth@hp.com>
- Cc: "public-cwm-bugs@w3.org" <public-cwm-bugs@w3.org>
What you are asking may be a bug. Before we get into that, let us give another example, to show what cwm was trying to do. Let us say you wrote a file ======= @prefix xsd: <http://www.w3.org/2001/XMLSchema#> . @prefix math: <http://www.w3.org/2000/10/swap/math#> . { ( "1"^^xsd:float "2"^^xsf:NCNAME ) math:sum ?x} => {?x a :Foo} . ======= what should it do? Cwm does not know how to add a float and an NCNAME, indeed, what you gave was not a valid NCNAME. Therefore, the rule should fail to fire. Similarly, if you wrote ======= @prefix xsd: <http://example/xsd#> . @prefix math: <http://www.w3.org/2000/10/swap/math#> . { ( "1"^^xsd:float "2"^^xsf:int ) math:sum ?x} => {?x a :Foo} . ==== Then cwm does not know what a http://example/xsd#int is, or how it is represented in a string, so it cowardly refuses to add it. In essence --- datatypes cwm does not know it will not run builtins on. On the other hand, cwm treats a http://www.w3.org/2001/XMLSchema#anyURI as being close enough to a string that string operations work on it. Thus the difference. Yosi On Thu, 2008-02-14 at 07:54 +0000, Booth, David (HP Software - Boston) wrote: > Hi Yosi, > > I don't know if this is a bug or not, but it sure seems odd, and it puzzled Sean > Palmer too. Depending on how the xsd namespace is declared, the rule below fires or doesn't fire. > > -------------------------------------------- > > # File: junk2.n3 > # Test with: > # cwm junk2.n3 --think --strings > # Gives the following with the right xsd namespace: > # FIRED base: http://example#aaa ex:p2 bbb > # Gives no output if the example namespace is used. > # > # Hmm, cwm seems to have special knowledge of the xsd namespace. > # If I declare it like this then the rule below fires, > # but if I declare it with an http://example namespace, it doesn't. > @prefix xsd: <http://www.w3.org/2001/XMLSchema#> . > # @prefix xsd: <http://example/xsd#> . > > @prefix ex: <http://example/httpspec#> . > @prefix log: <http://www.w3.org/2000/10/swap/log#>. > @prefix string: <http://www.w3.org/2000/10/swap/string#> . > > "http://example#aaa"^^xsd:anyURI ex:p1 <http://example#bbb> . > > { ?u ex:p1 ?reply . > ("FIRED base: " ?u " ex:p2 " > ?reply "\n") string:concatenation ?fired . > } => { > ?u ex:p2 ?reply . > # Debugging: > "a" log:outputString ?fired . > } . > > -------------------------------------------------- > > > David Booth, Ph.D. > HP Software > +1 617 629 8881 office | dbooth@hp.com > http://www.hp.com/go/software > > Opinions expressed herein are those of the author and do not represent the official views of HP unless explicitly stated otherwise. >
Received on Thursday, 14 February 2008 16:19:35 UTC