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From: Matthew Brealey <thelawnet@yahoo.com>
Date: Wed, 26 Jan 2000 04:25:15 -0800 (PST)
Message-ID: <20000126122515.26057.qmail@web903.mail.yahoo.com>
To: www-style <www-style@w3.org>
<blockquote>
outside
The marker box is outside the principal block box. Note. CSS1 did not
specify the precise location of the marker box and for reasons of
compatibility, CSS2 remains equally ambiguous. For more precise control of
marker boxes, please use markers.
</blockquote>

AFAICT, all this sentence leaves to the UA is the vertical alignment of
the marker box (since the horizontal offset is left to the UA by reason of
marker-offset anyway), and it is not possible to make any working
implementation that doesn't adopt the spec (which states that that the
baseline of a marker box should be aligned with the baseline of the first
line box in its principal box).

- once you have a definition of a marker box, the 'location' sorts it self
out.

I feel that what was actually meant was:

<blockquote>
outside
The marker box is outside the principal block box. Note. CSS1 did not
specify the precise definition of a marker box and for reasons of
compatibility, CSS2 remains equally ambiguous, at least in respect of
marker boxes generated by elements with display: list-item. For more
precise control of marker boxes, please use markers.
</blockquote>
, which is much closer to the truth.

In any case, it was a mistake to retain ambiguity where no ambiguity could
usefully be retained - clarifying the spec would have served only to
improve the quality of future user agents by standardising practice, while
the only effect on older user agents would be to retrospectively render
them incompliant (it is hardly as if this hasn't happened before). 

Clarification cannot cause problems with older user agents - it is only a
change that can cause this. As a result, I would suggest the following
changes:
<blockquote>
outside
The marker box is formatted in the same way as :before (or :after
depending on text directionality) {display: marker}.
inside
The marker box is formatted in the same way as :before (or :after
depending on text directionality) {display: inline}; however, user agents
SHOULD give the marker box padding or margin (note that it makes no
difference since they will both be transparent as you cannot specify the
styles of marker boxes created by display: list-item).
</blockquote>

I would also propose a change in:
marker-offset
Applies to:  
elements with 'display: marker'

to
marker-offset
Applies to:  
elements with 'display: marker' and 'display: list-item'

and:
Percentages:  
N/A

to:
Percentages:  
refer to width of principal block box

In addition:
<blockquote
cite="http://www.w3.org/TR/REC-CSS2/generate.html#before-after-content">
The formatting objects (e.g., boxes) generated by an element include
generated content. 
So, for example, changing the above style sheet to:
P.note:before { content: "Note: " }
P.note        { border: solid green }
would cause a solid green border to be rendered around the entire
paragraph, including the initial string.
</blockquote>

This fails to define the rendering of 
P.note:before { content: "Note: " ;
display: block}
P.note        { border: solid green }
- does the border cover the block before.

The spec does not say whether it does. Clearly the best answer is no, but
on the basis that it is also possible to infer the opposite conclusion,
the following examples (or words to the same effect) are omitted:

<EXAMPLE>
P.example:before {display: block}

would produce markup like this:

<BEFORE>
</BEFORE>
<P>
</P>

whereas
P.example:before {/* display: inline implied */}
would produce:

<P>
<BEFORE></BEFORE>
</P>
In both cases, inherited properties are 'inherited', even though in the
former case the BEFORE is not a descendant of the P element.
</EXAMPLE>



=====
----------------------------------------------------------
From Matthew Brealey (http://members.tripod.co.uk/lawnet (for law)or http://members.tripod.co.uk/lawnet/WEBFRAME.HTM (for CSS))
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Received on Wednesday, 26 January 2000 07:25:16 GMT

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