Re: [css-counter-styles] speak-as: auto and the override system

On Saturday 2014-05-10 10:23 +1000, Xidorn Quan wrote:
> On Thu, May 8, 2014 at 9:08 AM, L. David Baron <dbaron@dbaron.org> wrote:
> 
> > http://dev.w3.org/csswg/css-counter-styles/#counter-style-speak-as
> > says, when describing the 'auto' value:
> >   # If the system is override, this value has the same effect as the
> >   # overridden style’s speak-as.
> >
> > This has an unusual interaction with the definition of the override
> > system, which says in
> > http://dev.w3.org/csswg/css-counter-styles/#valuedef-override that:
> >   # If a counter style uses the override system, any unspecified
> >   # descriptors must be taken from the overridden counter style
> >   # specified, rather than taking their initial values.
> >
> > It means that when the override system is used, speak-as: auto is
> > equivalent to having an omitted speak-as, and is *not* equivalent to
> > the overridden system having speak-as: auto.  Both of these seem
> > wrong to me.
> >
> > Instead, I would propose that the 'auto' value say:
> >   # If the system is override, this value has the same effect that
> >   # 'auto' would have for the overridden counter style.
> > which seems more consistent with how the override system otherwise
> > works.
> >
> 
> To my understanding, there is no difference between your proposal and the
> current spec, though your wording seems to be clearer.

The difference is that given:

@counter-style base {
  system: cyclic;
  symbols: ‣;
  speak-as: numeric;
}

@counter-style derived {
  system: override base;
  speak-as: auto;
}

The current spec says that the counter style 'derived' is spoken as
numeric, whereas I propose that it be spoken as bullet (which is
what 'auto' means for the cyclic system).

(This is what your patches in [1] implement for 'speak-as', although
you followed the spec for the equivalent wording for 'range'.)

-David

[1] https://bugzilla.mozilla.org/show_bug.cgi?id=966166

-- 
𝄞   L. David Baron                         http://dbaron.org/   𝄂
𝄢   Mozilla                          https://www.mozilla.org/   𝄂
             Before I built a wall I'd ask to know
             What I was walling in or walling out,
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