Re: Typed CSSOM

On Sun, Sep 6, 2015 at 11:19 AM Alan Stearns <stearns@adobe.com> wrote:

> On 8/9/15, 6:05 PM, "Shane Stephens" <shans@google.com> wrote:
>
> >(2) Numbers
> >
> >
> >Number properties like z-index or opacity should have a very simple
> wrapping:
> >
> >
> >interface NumberValue : StyleValue {
> >  double value;
> >}
> >
> >
> >An open question: where and when does validation happen? What happens if
> I try to set an out-of-range number to opacity? Will this be consistent
> across all properties?
> >
> >
> >(3) Lengths
> >
> >
> >Usually, lengths are simple single-unit values (e.g. 50px or 30em).
> However, it is possible for calc values to be used instead.
>
> Numbers and integers can use calc() as well, which will be important for
> the SpecifiedStylePropertyMap.
>

Yup, good point. I think there's some simplification that goes on in calc
expressions between the text value they are initialized with and the typed
representation (e.g. calc(5% + 50px + 5%) will be represented as {percent:
10, px: 50}). I'm not sure if this means that number calc expressions get
removed completely before arriving at the typed representation.


> >
> >
> >Ideally, I'd like to either start incorporating some of this stuff in the
> CSS Properties and Values specification, or alternatively begin a new ED
> (CSSOM Level 2?) WDYT?
>
> Did we decide on whether this would be a separate spec? I’m using this
> deprecated email thing because I’m not sure if I should raise an issue on
> props and values, or wait for a new CSSOM draft to appear.
>

I *think* we decided separate spec. At any rate, it doesn't matter - having
all of the issues in one repo makes it trivial to relabel them later. So
file away!

Cheers,
    -Shane


>
> Thanks,
>
> Alan
>