The code you presented seems to be an algorithm implementing an
iterator over a tree. Because it maintains its state, it can be
stopped and resumed at will, provided you keep a reference to it.

If LMIter would have a reference to its parent LMIter, and could
return to it after having processed all the siblings, it would realize
such a construct. One could stop the iteration, retain a reference to
the active LMIter, and resume later.

Not being dependent on the Java stack would make the programming
much more robust. One would have more freedom to insert actions,
without the fear to lose the iteration state if one would not
carefully return to the same function.

Such a construct would be equally suitable to pull parsing. The LMIter
call to the LM method preLoadNext would request more child fo nodes,
which the parser would provide on this demand.

On Mon, Dec 13, 2004 at 08:29:43AM -0700, Victor Mote wrote:
> Finn Bock wrote:
> > Did you notice that if a FOTree (or a fragment of it) is 
> > serialized to a preorder sequential representation with end 
> > markers, the preorder, postorder and child events can be 
> > fired directly from the input stream?
> > 
> > IOW the event based layout can work both of a normal 
> > parent/children linked tree and a sequential tree.
> Hmmm. I must have totally misunderstood your original point, which I think
> you expressed much better in your second paragraph above. I certainly didn't
> mean to argue against event-based layout, which, in general, I support, but
> rather against the idea that an FOTree node can necessarily be laid out when
> it is first encountered. And I think I understand now why you have done the
> massive propagation of properties -- am I correct in understanding that you
> are essentially flattening the tree so that inheritance must be captured
> before that flattening takes place? Or are you simply making that an option
> now?

Do you want to traverse the FO tree, without relying on the Java
stack, and drive the layout process from there by firing node events?
Regards, Simon

Simon Pepping
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