Re: Backwards and Forwards Compatability

Orion Adrian wrote:

>To sum up: CSS can do advanced layouts using both contstant and
>percentage based values, but you shouldn't because it's short-sighted.
>  
>
No, in many cases it can be used just fine, it’s just not perfect yet 
for all situations. Some examples:

+-+-+-----+
|5|5|     |
+-+-+-----+

+---+-+
|10%|5|
+---+-+

+-+-+-----+--+
|5|5|     |5%|
+-+-+-----+--+

+-+----+---+--+
|5|    |10%|5%|
+-+----+---+--+

Those are all no problem to define with absolute positioning.

>I'm saying that there was this big argument that CSS could do certain
>layouts and didn't need changing. Well it can, but you shouldn't.
>  
>
No-one said that CSS didn’t need improvements.

What you were proposing however was a *replacement* for something that 
CSS for the most part can do already, and with a few changes could be 
further made to do so. That is what people (or at least I) were 
objecting against.

If you had made any constructive suggestions on how to improve absolute 
positioning as we currently have it, instead of saying that it sucks 
without even fully knowing how it works and considering such 
improvements first before throwing it all down the drain, I am sure 
people would have been happy to see those.

If you instead propose something that is supposed to be a replacement 
while it has certainly got a lot of overlap with what exists *right 
now*, whose main vantage point is the ability for ‘dynamic growth’ which 
*will never be used in practice*, and which in addition to that also 
*misses a lot of functionality that we currently have* (offset from the 
right, non-em units). Then yeah, it will be critisised, and discarded.

>I'm saying that CSS is in a state that it must be abused to get the
>desired output.
>  
>
Well, yes, depending on what you want. CSS can *not* do everything. 
Nothing probably will. CSS currently facilitates for a certain amount of 
things, but authors want to do things beyond what is currently possible 
in CSS, and start using properties for different things than they were 
originally intended for (e.g. margins and floats).

As CSS matures further, it will be able to do more. But it is a 
specification that is developed incrementally, with a number of 
in-progress milestone specifications that are implemented by user 
agents, but which do not have the full spectrum of abilities yet.

And that is only logical! After all, if CSS were able to do everything 
already, there would be no need to develop it further anymore.

Besides, it also benefits from implementation experience. It is likely 
that in order to get a good impression of what was still missing for 
absolute positioning, it would first need implementations and see some 
use. It is always easy critisising on hindsight.

>Secondly because the mechanisms (i.e. left, right, top, bottom) aren't
>tied together it's possible to have only two work and end up with
>something totally non-sensicle.
>  
>
That’s nonsense. No sensible implementor will implement absolute 
positioning without left, right, etcetera. Similarly no implementor will 
only implement left and bottom.

Or, well, actually... IE does, with width: and height: auto. Hehe. Not 
funny, really. The specification has a whole section dedicated to how 
width should work in an absolute positioning context [1], and still IE 
failed to implement it right, severely harming the usability of absolute 
positioning.

But I wouldn’t be surprised if that can be blamed on the lack of a good 
test suite, back then.

Anyways, they are also all in the same section of the CSS 2.1 
specification [2], and left/right/top/bottom are explicitly referenced 
in the absolute positioning definition, so I do not think the CSS 
specification lacks in clarity in this respect, that you cannot 
implement the one without the other.


~Grauw

[1] http://www.w3.org/TR/CSS21/visudet.html#abs-non-replaced-width
[2] http://www.w3.org/TR/CSS21/visuren.html#positioning-scheme

-- 
Ushiko-san! Kimi wa doushite, Ushiko-san!!
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Laurens Holst, student, university of Utrecht, the Netherlands.
Website: www.grauw.nl. Backbase employee; www.backbase.com.

Received on Wednesday, 13 July 2005 15:32:23 UTC