Re: [css-containment] Splitting the "sizing" part from "layout" containment

On Mon, Mar 21, 2016 at 2:29 AM Florian Rivoal <> wrote:

> Splitting sizing from layout makes sense to me.
> As for one property vs two, I think the key question is, as it often is
> when we run into this debate, do these two things benefit from the ability
> to cascade separately.
> If you're using them on (web) components, I don't think there's a benefit.
> Which type of containing might be different on different components, but
> for each component you'll want to decide on all 4 aspects of containment.
> On the other hand, if you do want to use the containments other than
> sizing in a heavy handed way all across your page, and separately add
> sizing containment without changing the other aspects of containment, then
> it makes sense.
> Would you? I can see adding all-but-sizing all over the place, and
> specifying some-specific-combo-which-may-include-sizing on components in
> the same page. But would you do all-but-sizing all over the place, and ADD
> sizing without wanting to change whatever the rest was in specific parts?
> If the answer's yes, then two properties are better, but what's the use
> case?

This seems extremely rare to me. I think the 99.99% use case is to use one
of strict or strict-compatible. Hence my thinking that we should have a
single property.

>  - Florian
> On Mar 19, 2016, at 09:50, Ojan Vafai <> wrote:
> There are two important use-cases here:
> 1. A simple way to get strong containment without needing to understand
> the intricacies of the platform and of each vendor's implementation. This
> is "style layout paint size".
> 2. A simple way to get soft containment that can be used broadly (e.g. via
> "* { contain: strict }"). This is "style layout paint".
> #1 is an extension of #2 and I think it should read that way. Also, it's
> really critical that #1 be very simple. It's just so draconian that it
> can't be used as the 90% use-case. But it's really critical for that other
> 10%.
> It seems to me that we just have a naming problem here, but that we can
> still have a single property. I think "strict" is a good name for #1. We
> just need to make a name for #2 that sounds like the pre-cursor to #1.
> Here's a few proposals:
> a) strictish
> b) strictable
> c) strict-candidate
> d) pre-strict
> I prefer (c), but would be happier with any of these than splitting this
> up into two properties.
> On Fri, Mar 18, 2016 at 11:24 AM Paul Lewis <> wrote:
>> Thanks for the clarification! SGTM.
>> Seems like a good addition irrespective of containment. Mainly I'm happy
>> if strict doesn't require explicit widths and heights. If there's a way to
>> ensure that independently then yay.
>> On Fri, 18 Mar 2016, 18:18 Tab Atkins Jr., <> wrote:
>>> On Fri, Mar 18, 2016 at 11:14 AM, Paul Lewis <> wrote:
>>> > If we go with a separate property then that restores the clarity of
>>> contain,
>>> > which is good.
>>> >
>>> > The concern I would have then is what this other property looks like. I
>>> > guess it comes like flex properties, which only apply when the parent
>>> is
>>> > display: flex?
>>> >
>>> > So I guess, yeah, if a developer sets this additional property along
>>> with
>>> > width and height (does it need both?) then there's an extra constraint
>>> > applied, but for the main case "strict-ish" just got promoted to
>>> "strict"
>>> > and we make this sizing property, in conjunction with the other, the
>>> "super
>>> > strict" option? :)
>>> Nah, the idea is that you'd have something like "height-foo: auto |
>>> pretend-you-are-empty;" (all names subject to change, obviously).  It
>>> would be completely disconnected from 'contain', and it applies to all
>>> elements at all times.  If you set it to "pretend-you-are-empty", then
>>> you need to either provide a value for 'height' as well, or your
>>> element will break in an obvious way, as it immediately collapses to
>>> zero height.  Similar for 'width'.
>>> ~TJ

Received on Monday, 21 March 2016 19:07:36 UTC