Re: [web-annotation] Selecting more than text

On Wed, Nov 11, 2015 at 5:23 AM Benjamin Young <bigbluehat@hypothes.is>
wrote:

> On Tue, Nov 10, 2015 at 5:21 PM, Randall Leeds <randall@bleeds.info>
> wrote:
>
>> .../p/node()[1] to ../p/node()[3] would select the first text node and
>> the image.
>>
>> If you wanted to select only part of the first text node than you would
>> need to further refine that.
>>
>> Since XPath to select the text would cause the evaluator to return a
>> string rather than a node, I suggested on that GH issue that a full
>> selector for each end of the range makes processing easier. A subSelector
>> on the start could refine the start point to be inside the text node.
>>
>
> In which case, this is starting to make a lot of sense. :)
>
> This would give us a way to further qualify both the beginning and end of
> a selection--while grabbing everything in between.
>
> Randall, do you have cycles to do some implementation exploration on the
> current Range and XPathSelector things we've been tossing around?
>
>
Already have been.

The Range utilities in Annotator were factored out in the past into the
xpath-range library. I've since released a new version of it that tries to
strip it down to a simple API.

https://github.com/openannotation/xpath-range

Going from Range -> Selector, the original API included a way to ignore
certain nodes in the XPath expression generation. I removed that.

Going from Selector -> Range, I tried finding a way to take just XPath
expressions, with no offsets, but realized that there was no way to do this
without having to parse out the offsets from a substring expression anyway,
so I made them explicit parameters.

The biggest problem with this library as is is that the Range is assumed to
point to text nodes -- the offsets are treated as text offsets -- but this
isn't made clear. Instead, it should handle Range objects that have
boundary containers in Elements or Text. For the latter I would generate
sub-selectors, as I've been describing in this thread.