[lxml-dev] DOM2 range() support?

[Stefan Behnel]

Hi,

just continuing this discussion on the right mailing list (from XML-SIG).

Gloria W wrote:
> I need to be able to do DOM2 range() functionality, to meet the
> requirements of a back end Dojo interface I have written in Python.
> I have already written my own DOM2 compliant node schema, out of
> necessity, but without the range functionality, since it is so tedious.
> I have forced a requirement on my Dojo developer colleague to not make
> use of range() for the time being.
> I wish it were properly supported in Python, but for the time being, I
> seem to be the only person needing it.

This is actually the first time I come across the concept of DOM2 ranges.

http://www.w3.org/TR/DOM-Level-2-Traversal-Range/ranges.html

Please correct me, but from a quick look at this:

http://www.w3.org/TR/DOM-Level-2-Traversal-Range/ranges.html#Level-2-Range-Definitions

isn't that simply a tuple of two positions, where each position contains an
Element and optionally one of the following:

- an attribute "{ns}name" and a string position in the attribute value
- a string position in the text
- a string position in the tail

Admittedly, the DOM2 interface on top of that is a little more complex and
(should I say it?) DOM-ishly obfuscated, but there shouldn't be more to it
than that, right? I mean, the respective W3C spec is only some 13 sections
long, there *can't* be more than that. :)

Hmm, now that we have cool HTML support and CSS selection, I wouldn't mind
having a Range class hanging around in some (lxml.range?) module. Doesn't even
sound like you'd have to implement it in Pyrex, Python code should be enough here.

Stefan