Re: Q: XML2JSON converter

> From: Code for Libraries [mailto:CODE4LIB_at_LISTSERV.ND.EDU] On Behalf Of
> Ross Singer
> Sent: Friday, March 05, 2010 09:18 PM
> To: CODE4LIB_at_LISTSERV.ND.EDU
> Subject: Re: [CODE4LIB] Q: XML2JSON converter
> 
> I actually just wrote the same exact email as Bill (although probably
> not as polite -- I called the marcxml "collection" element a
> "contrivance that appears nowhere in marc21").  I even wrote the
> "marc21 is EOR character delimited files" bit.  I was hoping to figure
> out how to use unix split to make my point, couldn't, and then
> discarded my draft.
> 
> But I was *right there*.
> 
> -Ross.

I'll answer Bill's message tomorrow after I have had some sleep :) 

Actually, I contend that the MARC-XML collection element does appear in MARC (ISO 2709), but it is at the physical layer and not at the structural layer.  Remember MARC records were placed on a tape reel, thus the tape reel was the collection (container).  Placed on disk in a file, the file is the collection (container).  I agree that it's not spelled out in the standard, but the concept of a collection (container) is implicit when you have more than one record of anything.

Basic set theory: a set is a container for its members :)

The obvious reason why it exists in XML is that the XML infoset requires a single document element (container).  This is why the MARC-XML schema allows either a collection or record element to be specified as the document element.  It is unfortunate that the XML infoset requires a single document element, otherwise you would be back to the file on disk being the implicit collection (container) as it is in ISO 2709.


Andy.