Re: [css-regions][css-overflow] enhancing overflow:fragments use case 2

On 10/7/13 5:54 PM, "Alan Stearns" <stearns@adobe.com> wrote:

>Hey all,
>
>The next case I'd like to describe is taking an instance of
>overflow:fragments and enhancing what's available to a JavaScript
>developer by adding a named flow. There are a lot of capabilities we've
>defined in Regions CSSOM [1] that are applicable and potentially useful in
>an overflow:fragments layout.


I have a further point to make on the CSSOM we've defined for named flows.
Making the results of fragmentation discernable via script allows all
sorts of extensions to the basic named flow functionality we define in the
spec. The named flow CSSOM is 'explaining' fragmentation in the Extensible
Web Manifesto sense [1].

Explaining and exposing the feature in this way allowed the people working
on book.js to implement footnotes [2]. While there is a declarative scheme
for footnotes defined in GCPM, they were able to make footnotes work in a
browser that had not yet implemented GCPM-style footnotes. They were also
looking into supporting margin notes, which we don't yet have a
declarative plan for.

Someone else might want to number the boxes in a region chain, or display
a word count. I would hope and expect that we will never get around to
defining a CSS property for declaratively adorning a box with word count
information. But I think it's a strength of the named flow CSSOM that this
*could* be done via script.

And I'll note that the kinds of fragment box adornments I'm bringing up
here are most easily accomplished when the fragment boxes are elements.
Being able to add a ::before or ::after box to your fragment box makes
these extensions possible in current browsers. If fragment boxes are
limited to pseudo-elements, new pseudo-element functionality would need to
be defined and implemented to add these adornments.

Thanks,

Alan

[1] http://extensiblewebmanifesto.org/
[2] http://lists.w3.org/Archives/Public/www-style/2013Apr/0211.html

Received on Monday, 14 October 2013 00:11:48 UTC