- From: Ryosuke Niwa <rniwa@apple.com>
- Date: Wed, 06 May 2015 20:54:20 -0700
- To: Hayato Ito <hayato@chromium.org>
- Cc: "Tab Atkins Jr." <jackalmage@gmail.com>, Anne van Kesteren <annevk@annevk.nl>, Elliott Sprehn <esprehn@chromium.org>, Domenic Denicola <d@domenic.me>, Justin Fagnani <justinfagnani@google.com>, WebApps WG <public-webapps@w3.org>, Erik Bryn <erik@erikbryn.com>, Dimitri Glazkov <dglazkov@google.com>, Edward O'Connor <eoconnor@apple.com>, Steve Orvell <sorvell@google.com>
> On May 6, 2015, at 6:18 PM, Hayato Ito <hayato@chromium.org> wrote: > > On Wed, May 6, 2015 at 10:22 AM Ryosuke Niwa <rniwa@apple.com> wrote: >> >> > On May 5, 2015, at 11:55 AM, Tab Atkins Jr. <jackalmage@gmail.com> wrote: >> > >> > On Tue, May 5, 2015 at 11:20 AM, Ryosuke Niwa <rniwa@apple.com> wrote: >> >>> On May 4, 2015, at 10:20 PM, Anne van Kesteren <annevk@annevk.nl> wrote: >> >>> >> >>>> On Tue, May 5, 2015 at 6:58 AM, Elliott Sprehn <esprehn@chromium.org> wrote: >> >>>> We can solve this >> >>>> problem by running the distribution code in a separate scripting context >> >>>> with a restricted (distribution specific) API as is being discussed for >> >>>> other extension points in the platform. >> >>> >> >>> That seems like a lot of added complexity, but yeah, that would be an >> >>> option I suppose. Dimitri added something like this to the imperative >> >>> API proposal page a couple of days ago. >> >>> >> >>> >> >>>> One thing to consider here is that we very much consider distribution a >> >>>> style concept. It's about computing who you inherit style from and where you >> >>>> should be in the box tree. It just so happens it's also leveraged in event >> >>>> dispatch too (like pointer-events). It happens asynchronously from DOM >> >>>> mutation as needed just like style and reflow though. >> >>> >> >>> I don't really see it that way. The render tree is still computed from >> >>> the composed tree. The composed tree is still a DOM tree, just >> >>> composed from various other trees. In the "open" case you can access >> >>> it synchronously through various APIs (e.g. >>> if we keep that for >> >>> querySelector() selectors and also deepPath). >> >> >> >> I agree. I don't see any reason node distribution should be considered as a style concept. It's a DOM concept. There is no CSS involved here. >> > >> > Yes there is. As Elliot stated in the elided parts of his quoted >> > response above, most of the places where we update distribution are >> > for CSS or related concerns: >> > >> > # 3 event related >> > # 3 shadow dom JS api >> >> These two are nothing to do with styles or CSS. > > I'd like to inform all guys in this thread that Composed Tree is for resolving CSS inheritance by the definition. > See the "Section 2.4 Composed Trees" in the spec: > http://w3c.github.io/webcomponents/spec/shadow/#composed-trees > > Let me quote: > > If an element doesn't participate in a composed tree whose root node is a document, the element must not appear in the formating structure [CSS21] nor create any CSS box. This behavior must not be overridden by setting the 'display' property. > > > In resolving CSS inheritance, an element must inherit from the parent node in the composed tree, if applicable. > > The motivation of a composed tree is to determine the parent node in resolving CSS inheritance. There is no other significant usages, except for event path. Event path / retargeting is definitely "event related", and it (e.g. deepPath) is definitely a part of "shadow DOM JS API". Again, they're nothing to do with styles or CSS. - R. Niwa
Received on Thursday, 7 May 2015 03:54:53 UTC