Re: [css21][css3-background] background-position examples conflict with prose/grammar

On Fri, 05 Mar 2010 01:48:35 +0100, Sylvain Galineau  
<sylvaing@microsoft.com> wrote:

> Update:
>
> #If two values are given and at least one value is not a keyword, then  
> the first value represents the horizontal position #(or offset) and the  
> second represents the vertical position (or offset). <percentage> and  
> <length> values here represent an #offset of the top left corner of the  
> background image from the top left corner of the background positioning  
> area.
>
> ...to:
>
> #If two values are given and one value is not a keyword, then the first  
> value represents the horizontal position #(or #offset) and the second  
> represents the vertical position (or offset). <percentage> and <length>  
> values here represent an #offset of the top left corner of the  
> background image from the top left corner of the background positioning  
> area. If both
> #values are keywords, the vertical and horizontal component can be  
> specified in either order.

That seems more ambiguous, and the presumably intended interpretation  
("exactly one value is not a keyword") is wrong since it wouldn't say how  
to interpret e.g. "background-position: 10px 40px".

Would a different wording be less confusing? E.g. "If two values are  
given, then unless both of them are keywords, the first value represents  
[...]". Or...

If two values are given and they are both keywords, the interpretation is  
given by the keywords and the vertical and horizontal components can be  
specified in either order. For other combinations of two values, the first  
value represents the horizontal position (or offset) and the second  
represents the vertical position (or offset). <percentage> and <length>  
values here represent an offset of the top left corner of the background  
image from the top left corner of the background positioning area.

-- 
Øyvind Stenhaug
Core Norway, Opera Software ASA