Hi Peter,

If I understand correctly, you are saying that in the following XML document:

    <l>A’ was a merry man—took up the child:</l>

    <l>“Yea,” quoth he, “dost thou fall upon thy face?</l>

    <l>Thou wilt fall backward when thou hast more wit;</l>

    <l>Wilt thou not, Jule?” and, by my holidame,</l>

    <l>The pretty wretch left crying and said “Ay.”</l>

one might want to insert additional markup around the quoted sentences. Something like this:

    <l>A’ was a merry man—took up the child:</l>

    <l><quote>“Yea,”</quote> quoth he, <quote>“dost thou fall upon thy face?</l>

    <l>Thou wilt fall backward when thou hast more wit;</l>

    <l>Wilt thou not, Jule?”</quote> and, by my holidame,</l>

    <l>The pretty wretch left crying and said <quote>“Ay.”</quote></l>

Is that the idea?

I can see how that is a problem for XML. XML does not allow start-tag/end-tag pairs that are not properly nested.

So the overlapping problem is this: Sometimes it's desirable to allow start-tag/end-tag pairs that are not properly nested.

Is that right?

Truthfully, the concept of allowing start-tag/end-tag pairs that are not properly nested doesn't seem like, in the universe of data concepts, a hugely important concept. I guess that I am not seeing its importance.

Are there data concepts that are not expressible by XML and are hugely important concepts?

By the way, here is the URL to Jeni's blog article: http://www.jenitennison.com/2008/12/06/overlap-containment-and-dominance.html

/Roger