[Laszlo-user] What should happen to a datapointer when you delete the node it is pointing to?

[P T Withington]

I think that there is a simple answer here:  If you want your xpath to  
try to match in the face of deletions, you set `rerunxpath`.  If you  
don't have that on, and you delete the node that was matched, you  
should get `null`.  _Maybe_ the intent of the original author was that  
if you have a nextSibling and delete yourself then even without  
rerunxpath you can figure you ought to now bind tothe next sibling,  
but that's really not accurate [you could certainly construct an xpath  
expression that would _not_ match if rerun were on].

Bottom line:  I agree if you delete yourself and don't have rerun on,  
you should be null.  (Which means the documentation and test case need  
to be revised.  Which means you are proposing an API change...)

My 2p.

On 2009-04-03, at 19:57EDT, Henry Minsky wrote:

> Hi Laszlo Users,
>
> This was discussed previously in a thread in Laszlo-Dev, but we  
> realized we
> should probably get people's opinion
> from Laszlo User before deciding on the 'correct' behavior. I need to
> resolve this bug by either changing
> the regression test to match the current behavior or changing the  
> behavior
> of the deleteNode method back to the
> older behavior.
>
> The bug is http://www.openlaszlo.org/jira/browse/LPP-7461
>
> And was discussed on laszlo dev back in December:
> http://www.openlaszlo.org/pipermail/laszlo-dev/2008-December/018410.html
>
> Currently, the documentation says
>
> datapointer.deleteNode();
> Removes the node pointed to by the datapointer. If rerunxpath is  
> true and
> xpath has been set, it will be re-evaluated. Otherwise, if the  
> deleted node
> has a following sibling, the pointer is repositioned at that sibling.
> Otherwise the pointer is set to null.
>
>
> However, the current behavior actually will back up the pointer to a
> previous sibling if there is no next sibling.
>
>
>
>
> -- 
> Henry Minsky
> Software Architect
> hminsky at laszlosystems.com