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I have a specific problem I'm facing currently,

I'm designing a component system for an engine that I'm writing myself and I'd like to do something like this:

trait BaseComponent {
  fn dimensions(&self) -> Dimensions;
  fn topleftmost_point(&self) -> Point;
  // other methods etc...
}

I want all components to implement this trait, but also one or more of these subtraits:


trait Component: BaseComponent {
   type State;
    
   fn draw(&mut self, ctx: &mut RenderContext<Self::State>) -> crate::Result<()>;
}

trait DynamicComponent: Component {
   fn update(&mut self, ctx: &mut RenderContext<<Self as Component>::State>) -> crate::Result<()>;
}

trait AsyncComponent: BaseComponent {
   type State;

   fn poll_draw(self: Pin<&mut Self>, ctx: &mut AsyncRenderContext<'_, Self::State>) -> Poll<crate::Result<()>; 
}

I also have planned for a async and blocking version of a stateless component, which is similar without the extra ctx parameter.

My question is, would there be a way to automatically require any object that implements the BaseComponent trait also implement one or more of these subtraits? It's not entirely necessary, but I feel like it could for sure eliminate some dumb errors I could potentially make.

UPDATE:

after about a day of trying different solutions, I found a system that at least partially works (it works for marker traits)

#![feature(marker_trait_attr)]

use core::marker::{PhantomData};

trait A 
where
    Comp<Self>: Coerce<dyn A>
{}

trait B: A {}

trait C: A {}

#[marker] trait Coerce<T: ?Sized> {}

impl<T: ?Sized + B> Coerce<dyn A> for Comp<T> {}

impl<T: ?Sized + C> Coerce<dyn A> for Comp<T> {}

struct Comp<T: ?Sized>(PhantomData<T>);

struct D;

struct E;

impl A for D {}
impl B for D {}

impl A for E {}
impl C for E {}




fn main() {}

the main issue of this, however, is that it is based off of unstable features, due to the marker trait attribute.

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