W3C home > Mailing lists > Public > www-style@w3.org > February 2015

Re: Shadow tree style isolation primitive

From: Olli Pettay <olli@pettay.fi>
Date: Tue, 03 Feb 2015 13:06:44 +0000
Message-ID: <54D0C7E4.4060306@pettay.fi>
To: Dimitri Glazkov <dglazkov@google.com>, "www-style@w3.org" <www-style@w3.org>, WebApps WG <public-webapps@w3.org>
CC: Brian Kardell <bkardell@gmail.com>
On 02/02/2015 09:22 PM, Dimitri Glazkov wrote:
> Brian recently posted what looks like an excellent framing of the composition problem:
> https://briankardell.wordpress.com/2015/01/14/friendly-fire-the-fog-of-dom/
> This is the problem we solved with Shadow DOM and the problem I would like to see solved with the primitive being discussed on this thread.

random comments about that blog post.

"Its intuitive then to create a combinator in CSS which allows you to select the mount explicitly"
Yes, I agree with that assuming the mount actually wants to be selectable.
And even if all the mounts were selectable, we don't have atm a way to select some particular
mount explicitly. And I think we should have that explicitly-ness. >>> or /deep/ are like
select all and cross your fingers you selected what you wanted, and not anything more.
We need to be able to select mount nodes explicitly, and perhaps explicitly say that all such nodes should be selected.
So, maybe, deep(mountName) and deep(*)

"It still needs to be possible from the hosting page to say “Yes, I mean all buttons should be blue”"
I disagree with that. It can very well be possible that some component really must control the colors itself. Say, it uses
buttons to indicate if traffic light is red or green. Making both those buttons suddenly blue would break the whole concept of the

Without the explicitly-ness we're back having the initial problems we're trying to solve, as the
blog says
"That is, preventing accidental violence against your allies is really hard – it’s simply too easy to accidentally select and operate on elements that 
aren’t “yours“. "
Same explicitly-ness should apply to things like Event.path etc.

(I still think shadow DOM needs proper encapsulation, even if components would all be 'allies'. A use case for encapsulation
would be rather similar to private: or protected: in many languages. But encapsulation is perhaps a bit different issue from
weaker isolation.)

Received on Tuesday, 3 February 2015 13:07:11 UTC

This archive was generated by hypermail 2.4.0 : Friday, 17 January 2020 22:52:01 UTC