Re: [css-variables] ...let's change the syntax

_property is a common CSS hack targeting IE6. So those in-the-wild stylesheets would suddenly start being interpreted as variables by modern browsers.

Maybe not a big deal...

Aesthetically, I find underscores in CSS files displeasing.

An issue we're bumping into in the sass community now is namespace collisions from 3rd-party libraries. It would be nice if CSS could avoid our mistake by forcing a namespace for custom properties.

Is there any reason we can't use dot notation for this?

div {
  my.color: red;
  bootstrap.color: blue;
  color: my.color;
  background-color: bootstrap.color;
}

And yes, I think we should have right hand side symmetry with the declaration. 

Chris



> On Mar 12, 2014, at 8:38 PM, "Tab Atkins Jr." <jackalmage@gmail.com> wrote:
> 
> I've been thinking.
> 
> At the last f2f, I proposed custom MQs and pseudo-classes.  To
> distinguish them from CSS-defined ones, I mandated that they had to
> start with (or perhaps just contain) an underscore character, because
> this is a valid character that CSS is nevertheless never going to use
> in language-defined names.
> 
> This, while a little ugly, seems to do the job pretty well.
> 
> Simultaneously, I'm wrestling with the fact that basically nobody
> understands that one of the primary use-cases of Custom Properties is
> to do CSS polyfills, where you write your own properties with a "var-"
> prefix and interpret them with JS.  This avoids the "have to re-parse
> the whole stylesheet yourself, and woe unto you if it's cross-origin"
> problem that today's CSS polyfills have.  From what I can tell, it's
> the "var-" prefix that's misleading everyone - it's *so* closely tied
> to var(), mentally, that it prevents people from imagining any other
> use.
> 
> Given that "tie it to var()" was one of my explicit justifications for
> sticking with the "var-" prefix, I'm very aware of how much I've
> hoisted myself by my own petard.
> 
> So, suggestion.  Assuming that we're sticking with the underscore
> thing for custom MQs/pseudo-classes/etc, I think we should move the
> syntax of Custom Properties to "any ident starting with/containing an
> underscore" as well.  This'll tie the syntax more closely to the
> *other* "custom" things, which hopefully will lead to it being more
> obvious that this is literally a CUSTOM PROPERTY, not just a variable
> definition.
> 
> The var() syntax is unchanged - the argument just switches to being
> literally the property name, rather than the property name minus the
> prefix.
> 
> I talked to heycam about this a few hours ago, and he said that
> Firefox is ready to ship Variables Real Soon Now, but this is a minor
> enough change that it can be swapped in real quick and not delay
> shipping if we decide on it quickly.
> 
> I've given myself a self-imposed deadline of until the next conf call
> to decide on this; if we say nay, or just don't decide, I'll happily
> stick with what's currently in the draft, and let Firefox ship with
> it.  However, I'd like to spend the next week deciding whether we
> should change the spec on this or not.
> 
> Thoughts?
> 
> ~TJ
>

Received on Thursday, 13 March 2014 04:40:32 UTC