Re: [css3-lists] Too many list styles and a proposal to simplify them

> [Original Message]
> From: Jungshik Shin <jshin@mailaps.org>
>
> Ernest Cline wrote:
>
> > cjkv-ideographic <string> <string>?
> > This is a generalized version of the "cjk-ideographic"
> > 'list-style-style'. The 'v' got added both because CJKV
>
> ....
>
> > The first string would be required to contain 16 characters,
> > if it did not, then the list style would be treated as if it were
> > "decimal".   The sixteen characters would be in this order:
>
> ...
>
> > Second Group Marker
> > Third Group Marker
> > Fourth Group Marker
> > 
> > The range of values that could be represented is from
> > 1 to 9,999,999,999,999,999. Values outside that range
> > would be treated as if the list style were decimal
>
>  CJKV ideographic system can represent numbers up to 10^72-1 :-) See
>
> http://lists.w3.org/Archives/Public/www-style/2003Apr/0063.html

While going past the 4th Group Marker may be correct, it would be
hard to implement.  There are values using the 5th Group Marker
that cannot be represented using a 64 bit signed integer.  Some
values using the 4th Group Marker cannot be represented by an
IEEE double.  There are values that use the 3rd Group marker
that cannot be represented using a 32 bit signed integer  These
limits are significant because in the HTML DOM, the value for list
markers is of type long which translates to a 32 bit signed integer
in Java and an IEEE double in ECMAScript.  Hence anything
beyond the 4th Group Marker is worthless for current UAs and
even with a 64 bit integer, worrying about anything beyond the
5th Group Marker is pointless.

CSS 3 Generated Content needs to specify the minimum acceptable
range for counter values.  Given the values used in HTML DOM,
the range -2^31 to 2^31-1 (32 bit integer) seems like a reasonable
minimum.  (There is nothing I can see in the DOM that would prevent
using a greater range for CSS counter values if desired, but requiring
a greater range would likely cause some otherwise conformant
implementations to be non-conformant for little gain.)

Received on Tuesday, 16 March 2004 14:20:33 UTC