Re: child wrappers

On Tuesday, April 8, 2003, at 09:03  PM, Adam Megacz wrote:
> When you add a child to a box, it will trigger a template
> application... but templates are only supposed to be applied in a
> *background* thread.  This means you can't add children to a box in
> the foreground thread.  That's not acceptable.

If you add a box to a parent, is the prerender pipeline guaranteed to 
be executed before the next line of code? I always thought not, in 
which case:

Have it check if it's in the foreground thread, and if so use a plain 
box as the wrapper and move the template application into a new 
background thread.

Your only difficulty would be the _0 trap inside the template with the 
child wrapper redirect set. The only options are to either a) execute 
it with the possibility the wrapper template has not been applied, or 
b) move the _0 execution into the new background thread straight after 
the delayed apply.

I can't find anything in the ref that promises the _0 trap gets called 
in the same thread.

There would have to be extra temporary tracking records however, that 
would get a little messy. If the added box were removed in the same 
thread it was created in, you'd have to cancel the background thread. 
And then _0 would never be called.

It's all a lot messier than it should be.

d


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