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Re: ISSUE-7: FrameRequestCallback interface should be designated as Callback=FunctionOnly [Request Animation Frame]

From: Alex Russell <slightlyoff@google.com>
Date: Tue, 28 Jun 2011 01:15:31 +0100
Message-ID: <BANLkTi=+K+4TOsQmc56S4Tur3R2aTtY3Zw@mail.gmail.com>
To: pettay@mappi.helsinki.fi
Cc: Savil Srivastava <Savil.Srivastava@microsoft.com>, Cameron McCormack <cam@mcc.id.au>, Web Performance Working Group WG <public-web-perf@w3.org>
On Wed, Jun 1, 2011 at 11:54 PM, <pettay@mappi.helsinki.fi> wrote:

> Is there any reason to not allow objects?
>
> DOM Events happen to be one of the most commonly used
> interfaces using callbacks. For consistency callbacks should work the same
> way.
> (if they don't in geolocation, that could be a bug in that draft.
>  geolocation is a bit strange API anyway.)
>

Yeah, geolocation should have been done as an <input> type in the first
place, which would yeild a DOM event-oriented API for those callbacks
anyway.


> Supporting objects allows one to easily handle the state related to
> callback handling.
>

I'm really not seeing the value since unless the function is bound somehow,
the calling context is going to get reset inside the callback.

The meta point for me, however, is that WebIDL shouldn't be serving Java at
all. We shouldn't allow a binding language that statistically nobody uses
make things worse for JavaScript in any way.


> Lainaus "Savil Srivastava" <Savil.Srivastava@microsoft.**com<Savil.Srivastava@microsoft.com>
> >:
>
>
>  Hi Olli,
>>
>> It would be helpful if you could provide a scenario where this capability
>> is useful in the context of RequestAnimationFrame. Highlighting how that
>> scenario could not be achieved via FunctionOnly callbacks or why it is more
>> desirable than the FunctionOnly approach would also be much appreciated.
>> This would make it easier to drive a decision (either way).
>>
>> Thanks,
>> Savil
>>
>> ______________________________**__________
>> From: public-web-perf-request@w3.org [public-web-perf-request@w3.**org<public-web-perf-request@w3.org>]
>> on behalf of Cameron McCormack [cam@mcc.id.au]
>> Sent: Wednesday, June 01, 2011 3:30 PM
>> To: Olli Pettay
>> Cc: Web Performance Working Group WG
>> Subject: Re: ISSUE-7: FrameRequestCallback interface should be designated
>>  as Callback=FunctionOnly [Request Animation Frame]
>>
>> Olli Pettay:
>>
>>> It is not. In event handling
>>> foo.addEventListener("bar_**event", { handleEvent: function(e) {}},
>>> true);
>>> has proved to be useful.
>>>
>>
>> I don’t know if it has proved to be useful, since it doesn’t really buy
>> you much over using a plain Function object, but DOM Events probably
>> needs to keep allowing this.  My impression is that new specifications
>> tend to use use [Callback=FunctionOnly] more than [Callback].
>>
>> --
>> Cameron McCormack ≝ http://mcc.id.au/
>>
>
>
>
>
>
Received on Tuesday, 28 June 2011 00:16:29 GMT

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