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Re: [css3-background] Nitpick on interpretation of one keyword+offset in background-position

From: Řyvind Stenhaug <oyvinds@opera.com>
Date: Thu, 07 Jan 2010 12:03:37 +0100
To: fantasai <fantasai.lists@inkedblade.net>
Cc: "www-style@w3.org" <www-style@w3.org>
Message-ID: <op.u55s0b0nru61ud@oyvinds-desktop>
On Thu, 07 Jan 2010 02:37:31 +0100, fantasai  
<fantasai.lists@inkedblade.net> wrote:

> On 01/06/2010 09:19 AM, Řyvind Stenhaug wrote:
>> The current text says "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)". There are a couple of cases where this is nonsensical, since
>> one can have
>>
>> <bg-position> = [ top | bottom ] [ <percentage> | <length> ]
>>
>> (e.g. "background-position: top 10px"), where the first value clearly
>> can't represent the horizontal position.
>
> That combination is forbidden by the property's value grammar:
>    http://www.w3.org/TR/css3-background/#the-background-position
> (This restriction is inherited from CSS2 and cannot be changed.)

As far as I can see the grammar does allow it. Drill down three times  
taking the second option each time and (after omitting the question mark)  
you get what I cited above. It's part of the fourth line (and the double  
bar doesn't need both options to be present).

-- 
Řyvind Stenhaug
Core Norway, Opera Software ASA
Received on Thursday, 7 January 2010 11:04:32 GMT

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