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So as a use case, I would refer to the ASN.1 gateway example presented
earlier. Are you saying that if a user creates a message (document)
specified as an <xsd:all> with three elements a, b, and c and chooses to
send them in the order b, a, c,
that this order must be preserved as it passes through the various gateways
to its final destination? If this is the case, I would agree there in no
ASN.1 equivalent.
Regards,
Ed Day
----- Original Message -----
From: "Alessandro Triglia" <sandro@mclink.it>
To: "'John Cowan'" <cowan@mercury.ccil.org>; "'Ed Day'" <eday@obj-sys.com>
Cc: <xml-dev@lists.xml.org>
Sent: Tuesday, November 25, 2003 5:33 PM
Subject: RE: [xml-dev] RE : [xml-dev] Comparison of Xml documents
>
> John Cowan wrote:
> >
> > Ed Day scripsit:
> >
> > > From a practical standpoint, an ASN.1 SET construct is roughly
> > > equivalent to an <xsd:all>. Both allow the elements
> > defined within to
> > > be transmitted in any order.
> >
> > In a word, the difference is that SET says the transmission
> > order has no meaning, whereas xsd:all says the order might or
> > might not mean something.
>
>
> In certain encoding rules (such as DER), the transmission order is fixed.
> Therefore the statement that SET allows the elements to be transmitted in
> any order is not a general statement about SET, but a statement about the
> manner that SET is encoded in a specific set of encoding rules.
>
> Transmission order of SET (when not fixed) is an example of what we call
> "encoder's options". Encoder's options exist for the convenience of
> encoders, but carry no information at all.
>
> Specifically, it would be a mistake to attribute any significance to the
> order of elements for a SET in the XML encodings. The abstract value is
> **unordered**, so the application should not be exposed to the order.
>
> Alessandro
>
>
> >
> > --
> > John Cowan jcowan@reutershealth.com www.reutershealth.com
> www.ccil.org/~cowan Promises become binding when there is a meeting of the
> minds and consideration is exchanged. So it was at King's Bench in common
> law England; so it was under the common law in the American colonies; so
it
> was through more than two centuries of jurisprudence in this country; and
so
> it is today.
> --_Specht v. Netscape_
>
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