How to parse simple xml file - rebol

Question

>> ? xml
No information on xml
There's parse-xml but it seems to me that it was for Rebol2.
I've searched for xml scripts in rebol.org and found xml-object.r that seemed to me like the most up to date from all searches.
I know about altxml, too, but the examples given are for html.
So, I'd like to ask about my choices if I want to parse and use information of +1GB of files of this simplified structure:
<?xml version="1.0" encoding="Windows-1252" standalone="yes"?>
<SalesFile xmlns="urn:StandardSalesFile-1.0">
<Header>
<SalesFileVersion>1.01</SalesFileVersion>
<DateCreation>2014-04-30</DateCreation>
</Header>
<SalesInvoices>
<Invoice>
<InvoiceNo>INV 1/1</InvoiceNo>
<DocumentStatus>
<InvoiceStatus>N</InvoiceStatus>
<InvoiceStatusDate>2014-01-03T17:57:59</InvoiceStatusDate>
</DocumentStatus>
</Invoice>
<Invoice>
<InvoiceNo>INV 2/1</InvoiceNo>
<DocumentStatus>
<InvoiceStatus>N</InvoiceStatus>
<InvoiceStatusDate>2014-01-03T17:59:12</InvoiceStatusDate>
</DocumentStatus>
</Invoice>
</SalesInvoices>
</SalesFile>
Is Rebol3 going to have a parse-xml tool? Should I use xml-object? If so how? Because it's still beyong my novice level of the language. Other option?

Answer 1

There is also a Rebol 3 library by Christopher Ross-Gill called alt-xml.
http://www.ross-gill.com/page/XML_and_REBOL
This can translate the XML to either a block! or object! representation.
Your question states that these XML files are large and may not fit in main memory. I would suggest that creating 1GB XML files is not best practice as many parsers, including this one, do attempt to load the files into memory.
To support this you will have to chunk the files yourself by using open on the file and copy/part chunks out of the file. This is a bit messy, but it will work.
One way to make this cleaner is to use parse as per HostileFork's suggestion and modify the series as you parse it. Parse is very flexible in this regard.
Ideally parse would be able to work directly on port! objects, but this is only a future wish list item at the moment.

Answer 2

Do you really need to deal with the XML file as structure? If not, have you considered just using PARSE?
(Warning: the following is untested, I'm just presenting the concept.)
Invoices: copy []
parse my-doc [
<?xml version="1.0" encoding="Windows-1252" standalone="yes"?>
thru <SalesFile xmlns="urn:StandardSalesFile-1.0">
thru <Header>
thru <SalesFileVersion> copy SalesFileVersion to </SalesFileVersion>
</SalesFileVersion>
thru <DateCreation> copy DateCreation to </DateCreation>
</DateCreation>
thru </Header>
thru <SalesInvoices>
any [
thru <Invoice>
(Invoice: object [])
thru <InvoiceNo> copy InvoiceNo to </InvoiceNo>
</InvoiceNo>
(Invoice/No: InvoiceNo)
thru <DocumentStatus>
thru <InvoiceStatus> copy InvoiceStatus to </InvoiceStatus>
</InvoiceStatus>
(Invoice/Status: InvoiceStatus)
thru <InvoiceStatusDate> copy InvoiceStatusDate to </InvoiceStatusDate>
</InvoiceStatusDate>
(Invoice/StatusDate: InvoiceStatusDate)
thru </DocumentStatus>
thru </Invoice>
]
thru </SalesInvoices>
thru </SalesFile>
to end
]
If you know you have well-formed XML and don't want a dependency on a library for processing clunky-ol' XML, Rebol can get pretty far and clear with PARSE. As TAG! is just a subclass of string, you can make things look relatively literate. And it's much more lightweight to just work with the strings.
Though if structural manipulations are required, you'll need something that makes a DOM. Altxml is the go-to right now, AFAIK.
(Hmm...I had a name for the pattern copy x to <foo> <foo> that escapes me at the moment, but this is a good case for it.)

Answer 3

%Rebol-Dom.r or %rebol-dom-mdlparser.r,
If your willing to use rebol2 with parse to seek thru to the node-name, then copy a chunk of data, you could feed that to Rebol-Dom.r getnodename "salesInvoice" and append that node-element to a block repetitively.