bonded<> recursive usage question

[codespare]

Hello, I am trying to get a combination of the generic_tree and polymorphic_container samples to obtain a polymorphic tree. But I cannot figure out how to serialize nested bonded<> fields, and I was wondering if that is supported?

[sapek]

You could define polymorphic tree like this:

struct Data
{}

struct Node;
struct Node
{
    0: nullable<Node> left;
    1: nullable<Node> right;
    2: bonded<Base> data;
}

You will need to serialize each node data to initialize the data field, like in the polymorphic_container example. You can also use generic Node<T>, either defining the data field as 2: bonded<T> data; or as 2: T data;. In the latter case you would use Node<bonded<Data>> instance.

[codespare]

Thank you, that got me unstuck. Ironically, that is much closer to the structure I am experimenting with(GumboParser) as opposed to the inheritance based model I was trying initially (conventional OO bias probably).
I have also tried the approach briefly mentioned in the 'Why Bond' article to emulate union with nullable<> and that works too. I still need to dig further to figure out the trade-offs in each approach.
Also, I am curious to understand when a mapping between a C and Bond model such as this one mandates the use of bonded<> and an interim serialization, versus when it can be made blittable, possibly using transforms, but no intermediate copy.