Re: [tcljava-user] (no subject)

[Mo D. <mo...@mo...>]

Dan Diolosa wrote:
>
> Hi,
>
>
> I am wondering why I need to "preserve" a TclList that I don't return 
> to TCL, nor need/use after the function returns.
>
> I am trying to return just one sub-list from a list of sub-lists.   If 
> I have just a list of normal TclObjects I can return one item without 
> a problem.   What is wrong with this:
>
Hi Dan

It is kind of odd, and the way you are using the list object is kind of 
odd too. I am sure there is some reason for it in your code, but
in this example you should be able to just set the interp result to 
list1 without having to create another container list. I don't see why
your code would need to preserve() the "list" variable, but it would 
need to release it after the interp.setResult() call in order to avoid
leaking memory. When a TclObject is created it should have a ref count 
of 0, if you then release() it is should then be deallocated. The
safest thing to do is to preserve() the container list, and then 
release() it (which will release any contained objects) after the 
interp.setResult()
call. The release should be in a finally block, in case an exception is 
thrown.

I hope that helps
Mo DeJong