Re: question about rules attributes...

> Setting flag : "dont-build-content" AND attribute parent="tree" just 
> don't draw anything ?
> Removing parent="tree" allows to draw an empty container that is 
> considered as a container... And is not, then the label disappear I 
> don't know why.
> 

It should work.

> IT SEEM IMPOSSIBLE to ask to draw only the first element WITHOUT 
> recursion... is this normal ?
> 

Currently, yes.

> Removing the "dont-build-content" flags allows to draw the correct 
> element without recursing...
> 
> And removing both make firefox enter an infinite loop and finally crash. 
> While this is understandable, it could be detected easily and quickly 
> with a recursion depth limit (as it is detected in javascript I suppose) 
> or a simple path checker.
> 
> I'm willing to help with this as I really need a little bit more solid 
> implementation of templates. Is someone willing to spend a little time 
> to present me how this works and is related to the rest of gecko's code, 
> and where I should look if I want to help ? Who is reviewer / 
> super-reviewer that are able to look on template code ?
> 

The issues you've mentioned in various posts are generally covered by 
the patch in bug 285631. It has support for conditional checks and 
disabling recursion.

/ Neil