Macro decorator 

macro_rules! decorator {
    ($plugin_name:ident : $name:expr; child($child_binding:ident),create: $create:expr,) => { ... };
    (
        $plugin_name:ident :
        $name:expr; child($child_binding:ident),params($params_binding:ident):
        $params_ty:path,create:
        $create:expr,
    ) => { ... };
}

Creates a decorator plugin for nodes that wrap a single child.

Minimal example with a bound child node:

struct Invert<N>
{
    child: N,
}

impl<N> Invert<N>
where
    N: Node,
{
    fn new(child: N) -> Self {
        Self { child }
    }
}

impl<N> Node for Invert<N>
where
    N: Node,
{
    fn tick(&mut self) -> TickStatus {
    }
}

decorator!(
    InvertPlugin: "Invert";
    child(child),
    create: Invert::new(child),
);

Parameters can be attached the same way as in action!.