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Derivations for recursive types

It seems like the derivation rules head out into crazy-land when we have type that may contain themselves, like

#[derive(Abomonation)]
struct TreeNode<D> {
    data: D,
    children: Vec<TreeNode<D>>,
}

When one attempts to use such a type with the T: Abomonation constraint, Rust complains thusly:

error[E0275]: overflow evaluating the requirement `TreeNode<i32>: abomonation::Abomonation`                                                                                          
  --> examples/types.rs:33:5                                                                                                                                                         
   |                                                                                                                                                                                 
33 |     test(&TreeNode::new(0));                                                                                                                                                    
   |     ^^^^                                                                                                                                                                        
   |                                                                                                                                                                                 
   = note: required because of the requirements on the impl of `abomonation::Abomonation` for `std::vec::Vec<TreeNode<i32>>`                                                         
   = note: required because of the requirements on the impl of `abomonation::Abomonation` for `TreeNode<i32>`

This doesn't seem to be a problem for serde, whose Serialize and Deserialize traits derive correctly enough to allow Rust to make progress. The unsafe_abomonate! macro produces implementations, but doesn't work with generic parameters.

Is this something that is expected to work, or perhaps annoying and non-trivial using syn, or .. any input you have would be great!

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