- From: Dirk Schulze <dschulze@adobe.com>
- Date: Mon, 25 Mar 2013 11:51:13 -0700
- To: Simon Sapin <simon.sapin@exyr.org>
- CC: "www-style@w3.org" <www-style@w3.org>
Hi, On Mar 25, 2013, at 9:02 AM, Simon Sapin <simon.sapin@exyr.org> wrote: > Kind of related to the rest of this thread. > > In the Level 3 spec for background-position: >> Note that a pair of keywords can be reordered while a combination of >> keyword and length or percentage cannot. So ‘center left’ is valid >> while ‘50% left’ is not. > > This is indeed reflected in the grammar: > (This is only the relevant part.) >> [ left | center | right | <percentage> | <length> ] >> [ top | center | bottom | <percentage> | <length> ] > > In CSS 2.1, the grammar also has this restriction. I checked the behavior of browsers and I checked the test suite for CSS Transforms. Both use/assume the syntax of CSS3 Background and Borders (with the exception of the missing offset). Not sure why the later one assumes it :P. Therefore, it should be no problem to fix that. I'll go ahead and do the change. Note that the syntax of perspective-origin is not different from transform-origin with the exception of the missing, third, optional value. > > transform-origin however removed this restriction: > >> [ <percentage> | <length> | left | center | right ] >> && >> [ <percentage> | <length> | top | center | bottom ] > > > Was there a reason to remove the restriction on one property but keep it > in others? I assume that this was an mistake. Thanks for noting. Greetings, Dirk > > -- > Simon Sapin >
Received on Monday, 25 March 2013 18:51:46 UTC