Re: XML 1.0 - Element order significance

[Tim Bray <tbray@textuality.com>]

At 09:09 AM 22/01/01 +0000, Henry S. Thompson wrote:
>Without looking at the DTD you can't tell.  Somewhat
>counter-intuitively, if the DTD says:
>
><!ELEMENT brothers (matthew,james,luke,david)>
>
>then you can infer that order is _not_ significant, since the grammar
>gives you no choice.
>
>If on the other hand it says:
>
><!ELEMENT brothers (matthew|james|luke|david)*>

I think Henry's view here is unusual.  At one level the order of
elements is *always* significant, i.e. whether I'm reading or
talking to a SAX or a DOM or whatever, if the doc has

<brothers><matt /><jim /><luke /><dave /></brothers>

then if I don't see them in the order (m, j, l, d) that they
appear in the document, something is wrong.  Software that 
rearranged the elements as part of processing would be broken;
fortunately, I've never heard of any software doing this.

As to whether the order is "significant" in the human/design/business
sense, that is totally language-specific, and I don't agree with
Henry that you can reverse-engineer it from the DTD. -Tim