Re: [CSS Intrinsic & Extrinsic Sizing] sizing of absolutely positioned elements

On Tue, Oct 9, 2012 at 3:56 PM, Anton Prowse <> wrote:
> On 10/10/2012 00:05, Boris Zbarsky wrote:
>> There's an unfortunate tendency to use the term "containing block" to
>> refer interchangeably to "the rectangle defined as the containing block"
>> (which is not itself a block in any way; it's just a rectangle) and "the
>> element which was used when defining the containing block" (assuming
>> there was one at all; see initial containing block) and maybe a few
>> other things.
>> As defined, right now, the containing block is a rectangle.  The other
>> uses are just confused, to a greater or lesser extent.
> Yup. Various people have raised these confused uses in CSS21 over the years.
> When I last looked through (in response to a detailed post by Peter Moulder,
> IIRC) I got the distinct impression that the containing block used to refer
> to a real block (box) in times gone by... but then, I imagine, the
> definition got repeatedly tweaked to account for eg abspos, and suddenly the
> containing block became a mere rectangle and various bits of existing spec
> text became out-of-kilter (not to mention that the term itself became
> seriously misleading).
> No post-CSS21 spec should be using the term to mean anything other than a
> rectangle, though (modulo the pending issue about containing blocks
> established by a principal inline box that's split across multiple lines).

We've got two options for rewording in the spec now, hidden behind a
comment below the existing text.  fantasai will work on them a bit
more to sanity-check, and then we'll bring them up here to see what we
want to do.


Received on Wednesday, 10 October 2012 00:22:14 UTC