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RE: [css3-transitions][css3-values] transition-duration's inital value is '0' without a unit

From: Sylvain Galineau <sylvaing@microsoft.com>
Date: Sat, 23 Oct 2010 02:35:36 +0000
To: "L. David Baron" <dbaron@dbaron.org>
CC: www-style list <www-style@w3.org>
Message-ID: <045A765940533D4CA4933A4A7E32597E2810CEA0@TK5EX14MBXC120.redmond.corp.microsoft.com>
> From: L. David Baron [mailto:dbaron@dbaron.org]
> Sent: Friday, October 22, 2010 7:06 PM
> To: Sylvain Galineau
> Cc: www-style list
> Subject: Re: [css3-transitions][css3-values] transition-duration's
> inital value is '0' without a unit
> 
> On Friday 2010-10-22 23:40 +0000, Sylvain Galineau wrote:
> > So either the former picks a unit or we extend the optional-unit-for-
> zero exception of <length>
> > to times for consistency. Although in the latter case it would seem
> coherent to do the same for
> > frequencies and angles as well. It's the bigger change but I lean
> towards the latter. It'd be
> > odd if width:0 was valid but not transition-duration:0 or
> transform:rotate(0). (Although that
> > ship may already have sailed, implementation-wise...).
> 
> The gradient syntax depends on unitless zero not being allowed for
> angles.  See the thread starting with
> http://lists.w3.org/Archives/Public/www-style/2009Nov/0043.html .  I
> believe we agreed on that at some point following the thread, though
> I'm not sure.

OK.
1. For <time> and transition-duration, both Firefox 4b6 and Chrome 7 return "0s". Can
we simply make this the initial value for transition-duration in the spec ?
2. For <angle>, my bad: I forgot that this would most likely always require a unit. 
The decision here seems to be whether existing transform implementations are wrong
or make an exception for them.
3. For <frequency>, do we make 0 <frequency> unitless.

Given the gradient issue, I am now a bit warier of making 0 values unit-less since
it could cause ambiguity in the future. 
Received on Saturday, 23 October 2010 02:36:25 GMT

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