Ewoc for trees

[Eric.Belpaire@equant.com]

Hello,

I'm looking for a way to manipulate trees of lisp objects and save those to
a file so that I can 'load' them again later.
I'm wondering whether ewoc.el could be extended or used as a stepping stone
to do this.

A tree's node can have zero, one or more children.
A tree's node can have zero, one or more parents.
A tree has a starting node, which usually has no parents.
Nodes without children are leaves.
There can be circular routes, i.e. links from a node back to the starting
node.

Instead of 'left', a tree would have 'parents' (defined as a list of
nodes).
Instead of 'right', a tree would have 'children' (defined as a list of
nodes).

I've drafted below the correspondence I envisage.

Can someone tell whether this makes sense?
Does someone know whether this has already been implemented?
Any suggestions?

Thanks in advance for any feedback provided.
Eric

;;   collection ==>  ewoc        ==> tree
;;   tin        ==>  ewoc--node  ==> tree_node
;;   cookie     ==>  data or element or elem ==> node_content

Eric BELPAIRE
Equant - CS&N / Access Technology
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