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Re: [webcomponents]: Changing API from constructable ShadowRoot to factory-like

From: Elliott Sprehn <esprehn@google.com>
Date: Thu, 8 Nov 2012 09:54:02 -0800
Message-ID: <CAO9Q3iLSc4fW1uLRLLcjKOxSREiHb-Z8Sc77MO9u_YaqOOf8yg@mail.gmail.com>
To: Dimitri Glazkov <dglazkov@google.com>
Cc: Maciej Stachowiak <mjs@apple.com>, public-webapps <public-webapps@w3.org>, Blake Kaplan <mrbkap@mozilla.com>, Jonas Sicking <sicking@mozilla.com>, Boris Zbarsky <bzbarsky@mit.edu>
The real sugar I think is in the dictionary version of addShadowRoot:

root = element.addShadowRoot({
  applyAuthorSheets: false,
  resetStyleInheritance: true
})


On Thu, Nov 8, 2012 at 9:49 AM, Dimitri Glazkov <dglazkov@google.com> wrote:

> Sure. Here's a simple example without getting into traversable shadow
> trees (those are still being discussed in a different thread):
>
> A1) Using constructable ShadowRoot:
>
> var element = document.querySelector('div#foo');
> // let's add a shadow root to element
> var shadowRoot = new ShadowRoot(element);
> // do work with it..
> shadowRoot.applyAuthorSheets = false;
> shadowRoot.appendChild(myDocumentFragment);
>
> A2) Using addShadowRoot:
>
> var element = document.querySelector('div#foo');
> // let's add a shadow root to element
> var shadowRoot = element.addShadowRoot();
> // do work with it..
> shadowRoot.applyAuthorSheets = false;
> shadowRoot.appendChild(myDocumentFragment);
>
> Now with traversable shadow trees:
>
> B1) Using constructable ShadowRoot:
>
> var element = document.querySelector('div#foo');
> alert(element.shadowRoot); // null
> var root = new ShadowRoot(element);
> alert(root === element.shadowRoot); // true
> var root2 = new ShadowRoot(element);
> alert(root === element.shadowRoot); // false
> alert(root2 === element.shadowRoot); // true
>
> B2) Using addShadowRoot:
>
> var element = document.querySelector('div#foo');
> alert(element.shadowRoot); // null
> var root = element.addShadowRoot();
> alert(root === element.shadowRoot); // true
> var root2 = element.addShadowRoot();
> alert(root === element.shadowRoot); // false
> alert(root2 === element.shadowRoot); // true
>
> :DG<
>
> On Thu, Nov 8, 2012 at 9:42 AM, Maciej Stachowiak <mjs@apple.com> wrote:
> >
> > Could you please provide equivalent code examples using both versions?
> >
> > Cheers,
> > Maciej
> >
> > On Nov 7, 2012, at 10:36 AM, Dimitri Glazkov <dglazkov@google.com>
> wrote:
> >
> >> Folks,
> >>
> >> Throughout the year-long (whoa!) history of the Shadow DOM spec,
> >> various people commented on how odd the constructable ShadowRoot
> >> pattern was:
> >>
> >> var root = new ShadowRoot(host); // both creates an instance *and*
> >> makes an association between this instance and host.
> >>
> >> People (I cc'd most of them) noted various quirks, from the
> >> side-effectey constructor to relatively uncommon style of the API.
> >>
> >> I once was of the strong opinion that having a nice, constructable
> >> object has better ergonomics and would overcome the mentioned code
> >> smells.
> >>
> >> But... As we're discussing traversable shadows and the possibility of
> >> having Element.shadowRoot, the idea of changing to a factory pattern
> >> now looks more appealing:
> >>
> >> var element = document.querySelector('div#foo');
> >> alert(element.shadowRoot); // null
> >> var root = element.addShadowRoot({ resetStyleInheritance: true });
> >> alert(root === element.shadowRoot); // true
> >> var root2 = element.addShadowRoot();
> >> alert(root === element.shadowRoot); // false
> >> alert(root2 === element.shadowRoot); // true
> >>
> >> You gotta admit this looks very consistent and natural relative to how
> >> DOM APIs work today.
> >>
> >> We could still keep constructable object syntax as alternative method
> >> or ditch it altogether and make calling constructor throw an
> >> exception.
> >>
> >> What do you think, folks? In the spirit of last night's events, let's
> vote:
> >>
> >> 1) element.addShadowRoot rocks! Let's make it the One True Way!
> >> 2) Keep ShadowRoot constructable! Factories stink!
> >> 3) Let's have both!
> >> 4) element.addShadowRoot, but ONLY if we have traversable shadow trees
> >> 5) Kodos.
> >>
> >> :DG<
> >>
> >> P.S. I would like to retain the atomic quality of the operation:
> >> instantiate+associate in one go. There's a whole forest of problems
> >> awaits those who contemplate detached shadow roots.
> >>
> >
>
Received on Thursday, 8 November 2012 18:40:28 GMT

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