@iari are you trying to do something like this?

@carlw more like this

The sealed class basically represents a node in a Tree. Nodes should know their Parent-nodes. Parents should also know their children.

I want the (implemented) Nodes to be data classes, so they can easily be copied and modified

Node is a Sealed Type, because there are going to be just two different Node Types that hold different data

Upon createion i want a node to register with its parent node as a child.

one of the sides needs to give way when the GC is called

maybe you're right - to be honest so far I have really not given any thought at all about memory stuff - i think right now my app has tons of leaks ^^

for my tree structure i had made an ObsevableMutableList .... which probably already exists somewhere, but whatever. So when children are added to a parent, it can be notified and set itself as the parent, or remove itself upon removal. so far it has worked, but like honestly i haven't done a lot of "delete" yet so 😄 could not be working as intended

im using these trees just as part of the generation of some ID's, they're quite short lived, and I don't really need to display them... so going the full observable route seemed a bit overkill to me

seems like one of those applications where the children shouldn't need to know about their parents

They're just used to transform an existing tree, keep part of its structure, but remove levels that have only one node without siblings

yep probably also true ... particularly with regard to the memory issue pointed out by @carlw

off to work 😞

I use the Event Bus (or my JavaFX custom equivalent) to get rid of parent references

...In the end I just need to know the sibling-count for any node

i could implement it without parent references, but then Id have to check the sibling count separatly in the end.. i dont know, for now it just works and the code is rather easy to read

do you think that the abstract val might be just a simple constructor arg?

yep ... I was thinking that too - for some reason that didn't work out though - I think it had to do with the implementation classes being data classes ... let me check again

constructor_arg.kt

where line number 3 is your keyholder add argument

hm, that might actually work

yep, works like a charm!

thats a nice and easy dirty hack to trick the order of execution and have things available at init of a parent class 😄

I'll keep that in mind

Here's a WeakReference example @iari

thx - im confused a bit though by the separation of the container from the node

just guessing at your problem. the key is that one side of the parent/child relationship will give way with the weak reference

yes, thanks again - the concept using the weak reference is clear to me I think

the problem is actually that I'm parsing a javascript file which, for the most part, contains a literal object, which is the tree structure