Derive Macro Module 

#[derive(Module)]
{
    // Attributes available to this derive:
    #[tree]
    #[module]
}

Derives Tree for a model (it emits no impl Module: Module is implemented for every tree), with one more check: a field typed Array (directly or in Option, Vec or Box) without buffer or skip is an error suggesting Param. The check is syntactic: a type alias of Array is not caught.