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Re: [CSS21] some feedback on PR

From: Alan Gresley <alan@css-class.com>
Date: Tue, 26 Apr 2011 02:49:24 +1000
Message-ID: <4DB5A614.7030005@css-class.com>
To: Brian Manthos <brianman@microsoft.com>
CC: Bert Bos <bert@w3.org>, W3C style mailing list <www-style@w3.org>
On 25/04/2011 8:26 PM, Brian Manthos wrote:
>> From: www-style-request@w3.org [mailto:www-style-request@w3.org] On
>> Behalf Of Bert Bos
>>      http://www.w3.org/TR/2011/PR-CSS2-20110412/
> I used the PDF version:
>          http://www.w3.org/TR/2011/PR-CSS2-20110412/css2.pdf
> For much of the CSS2.1 spec, I’m a first time reader so bear with me...

OK, so you are working backwards from CSS3 to CSS2.1. That's like going 
from the ballroom to the dungeon.

I have answered some of your questions that are not related to editorial.

> 2.      p45, Intrinsic dimensions
> a.      I don’t see “intrinsic ratio” defined anywhere, though referenced frequently.
> b.      Can it ever be negative?


> c.      Can it ever be zero or infinity?

If it is a SVG with no intrinsic ratio.

A 760px (width) by 570px (height) Bitmap image has an intrinsic ratio of 
4:3. If I declared just the height of the <img> at 300px, then it's 
width will be 400px.

> 5.      p82, 5.8.1 - Can these attribute selectors be applied to the style attribute itself?
> a.      h1[style~=blue]

Yes but you must use !important.

<!DOCTYPE html>

<style type="text/css">
   [style] {background: green !important;}

<p style="background:red">Test</p>

> 8. p151, 9.6, 3rd sentence - When I first read this, I found it
> confusing. I was under the impression that the APE content
> shouldn’t flow around floater siblings but *should* flow around
> floater children of that APE.  And now, I’m not sure if that’s
>correct or not.  Examples would help make it crystal clear.

Any content that overflows a parent with AP can not flow around any 
other boxes since it belong to the BFC of it's parent.

> 10. p162, hyphen example - Is there an expected relationship
> between the width of the pair of hyphens, 1em, and 10px?


> Or does the example break if the font size or face is changed
> such that the dashes become relatively wider?

No because the text is not size in ems. If the text wrap differently, 
the statement is always true.

   I used two red hyphens to serve as a
   change bar. They will "float" to the left of
--the line containing THIS word.

> 11.     p174,<percentage>  - “...the resulting layout
> is undefined...”  A good example describing a scenario
> that can trigger this would be helpful for people trying
>to understand this behavior for the first time (like me).

Possibly something like below. When I started with CSS, this could be 
buggy. Just a quick check shows that a vertical stroll bar shows when 
the text is more the 50% of the width of the viewport.

<div style="float: left">
<div style="width: 50%">Specifies a percentage width. The percentage is 
calculated with respect to the width of the generated box’s containing 
block [p. 128] . If the containing block’s width depends on this 
element’s width, then the resulting layout is undefined in CSS 2.1.</div>

> 13. p196, last paragraph - “it should be inserted between the
> inner border edge and the outer padding edge.”  Prior to
> reading this, I thought that scrollbars were supposed to
> eat into padding space, and then content (but I’m not 100%
> on that).  This phrasing suggests it should allocate additional
> space of its own - such that you have the content box, then
> the padding box, then a scrollbar width, then the border box.
> A diagram would be helpful here.

A resolution back in 2008 said that the padding-right (for ltr) should 
be clipped. I believe most browsers do that now. A reloaded test 
(browser reports are from 2007 or 2008).


I will add that this section on overflow and clipping and it's 
relationship to other parts of CSS2.1 will spin you around in circles.

> 14. p199, 2nd to last paragraph - “Content that has been clipped
> does not cause overflow.”  I think the intent was to say that
> the content *excluded* because of clipping should not cause
> overflow.  Inserting the word “out” after clipped would make
> that clearer.  On this page and subsequent pages, “clipped
> content” is used to refer to elements that have clip set at
> all, elements that have clip different from border box, the
> part included in the clip rectangle, and the part excluded
> from the clip rectangle.  I find it confusing to loosely
> refer to “clipped” without being explicit about “clipped
> out”, “clipped in”, “clip excluded”, or “clip excluded”.
> The first paragraph of p200 has similar issues.

See above.

> 18.     p214, “h1::before” - Typo (two colons)?

That is CSS3 syntax which has two colons.

> 21. p235

Page 233 you mean.

> , 14.2 - “either a color or an image”  When used elsewhere,
> “either A or B” is used to express alternatives.  Here you
> can specify both a color and an image.  Recommend: remove
> the word “either”; also consider changing to “and/or” or
> add a trailing “, or both” to the sentence.


> 23.     p238, ‘background-position’ - The term “initial
> position” here is troubling.  The diagram on page 237
>refers to the corresponding location as “center image”.

This example has 'background-position: center'

> I think it would be best to come up with an official term
> for “the base image position” (which is also not a great
> name, but hopefully gets the point across for this
> discussion).  Using “initial position” is easily confused
> with “initial value of background-position” which is
>something totally different (“0% 0%”).

Not sure what you mean here. If you give a background image no-repeat 
and no background position, then it sits at the top left of the border box.

> 24. p239, center - The block here is addressing both the
> meaning of the value and the interaction with other fields.
> I think it’s attempting to say too much, and complicating
> things.  Recommend: “Equivalent to ‘50%’ for whichever
>axis it is being applied to.”

On page 238 for 'background-position is this.

   | If only one value is specified, the second value is
   | assumed to be ’center’. If at least one value is not
   | a keyword, then the first value represents the
   | horizontal position and the second represents the
   | vertical position.

I think that what it is trying to express a few words.

Alan Gresley
Received on Monday, 25 April 2011 16:49:55 UTC

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