On Sat, Jun 7, 2008 at 7:41 AM, fantasai <fant...@inkedblade.net> wrote:

It's more complicated than that because of the rules for negative margin collapsing. You'll actually need at least three values, the min-negative, the max-positive, and the flex.

There will also be interesting interactions between flex-units and clearance. <div style="overflow:auto;" class="block-formatting-context"> <div style="height:1*;">Hello</div> <div style="float:left;">Kitty</div> <div style="clear:left;">Kitty</div> </div> Since we don't know the vertical positions until the end, we can't know whether to clear or not. If we treat 1* as auto while we compute clearance, the results are going to be really bad when we apply flex at the end.

I'm not saying these difficulties are insurmountable. But I hope it's clear that integrating flex-units into the existing CSS layout specs would create many issues that have to be analyzed and specified. It's not good enough just to wave our hands and say it's all obvious; the issues raised already are not obvious and we've only just scratched the surface.

(It's great that Andrew has an implementation, but it's often easier to implement a feature and say that whatever the implementation does is the desired behaviour, than it is to write a real spec with all the interactions worked out.)

So, we need a spec proposal that carefully considers all the possible interactions between flex-units and CSS layout where flex-units can be used, and describes how issues (such as the ones already raised) are resolved.

Rob