W3C home > Mailing lists > Public > public-rdf-wg@w3.org > May 2013

Re: json-ld-api: change proposal for handling of xs:integer

From: Manu Sporny <msporny@digitalbazaar.com>
Date: Sun, 12 May 2013 21:45:16 -0400
Message-ID: <519045AC.7030101@digitalbazaar.com>
To: W3C RDF WG <public-rdf-wg@w3.org>
On 05/10/2013 06:31 PM, Sandro Hawke wrote:
> I believe, by saying in situations where there might be a loss, one
> MUST NOT convert to a number.

We didn't do this because the range for a JSON number isn't defined
anywhere.

> It's true we don't know exactly when there might be a loss, but after
> talking with Markus, I'm pretty confident that using the range of
> 32-bit integers will work well.

... except that most systems support 64-bit numbers, and we'd be
hobbling those systems. :/

We might want to put in guidance that moves the decision to the
processor (it can detect when a conversion would result in data loss).
Perhaps it should be up to the implementation to determine when data
could be lost.

> I'd also add:
> 
> "1"^^xs:int              // not native since it's 'int' not
> 'integer' "01"^^xs:integer     // not native since it's not in
> canonical form

+1

> These rules will make xs:integer data round tripping through JSON-LD 
> perfectly lossless, I believe, on systems that can handle at least
> 32 bit integers.

Yeah, but I'm still concerned about the downsides of limiting the number
to 32-bits, especially since most of the world will be using 64-bit
machines from now on.

I do agree that we might be able to change the text to ensure that
precision loss isn't an issue, and I do agree with you that it's
definitely worth trying to prevent data loss.

Tracking the issue here:

http://lists.w3.org/Archives/Public/public-rdf-wg/2013May/0136.html

> On a related topic, there's still the problem of xs:double.  I don't 
> have a good solution there.   I think the only way to prevent
> datatype corruption there is to say don't use native number when the
> value happens to be an integer.

I don't quite understand, can you elaborate a bit more? Do you mean,
this would be an issue?

"234.0"^^xsd:double --- fromRDF() ---> JsonNumber(234)

-- manu

-- 
Manu Sporny (skype: msporny, twitter: manusporny, G+: +Manu Sporny)
Founder/CEO - Digital Bazaar, Inc.
blog: Meritora - Web payments commercial launch
http://blog.meritora.com/launch/
Received on Monday, 13 May 2013 01:45:53 UTC

This archive was generated by hypermail 2.4.0 : Friday, 17 January 2020 17:04:27 UTC