[css3-transitions] contradictory text about transitioning shorthands

I noticed that Dean and I both added text to address the issue about
specifying handling of shorthand properties, but we did so in
different and contradictory ways.  In
http://dev.w3.org/csswg/css3-transitions/#the-transition-property-property-
I added:
  #  If one of the identifiers listed is a shorthand property,
  #  implementations must start transitions for any of its longhand
  #  sub-properties that are animatable, using the duration, delay,
  #  and timing function at the index corresponding to the
  #  shorthand. 
and in
http://dev.w3.org/csswg/css3-transitions/#animation-of-property-types-
Dean added:
  # a shorthand property: If all the parts of a shorthand can be
  # animated, then interpolation is performed as if each property
  # was individually specified. 

The difference is that Dean's text requires all of the parts to be
animatable whereas mine says that any parts that are animatable
should be animated even if others are not.

I prefer my proposal because it is more forwards-compatible:  if the
working group turns an existing animatable property (say,
'text-indent') into a shorthand with some components that are not
animatable (say, to allow 'text-indent: 5em hanging'), my proposal
would not break existing content.

-David

-- 
L. David Baron                                 http://dbaron.org/
Mozilla Corporation                       http://www.mozilla.com/

Received on Sunday, 27 December 2009 02:02:11 UTC