- From: Tab Atkins Jr. <jackalmage@gmail.com>
- Date: Mon, 25 Mar 2013 11:11:12 -0700
- To: Simon Sapin <simon.sapin@exyr.org>
- Cc: www-style list <www-style@w3.org>
On Mon, 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. > > > 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? Sigh, no, that's just what happens when you redefine the same grammar production in multiple places - random mutations end up making them drift. ~TJ
Received on Monday, 25 March 2013 18:12:02 UTC