I wanted to create a derived macro of a trait to ensure that I could retrieve important values from my windows. This is the trait:

pub trait WindowValues<B>: 'static + Sized + Component + Default
where
    B: 'static + Sized + Hash + Component + Clone + EnumWindowColor + States,
{
    fn get_height(&self) -> f32;
    fn get_left(&self) -> f32;
    fn get_width(&self) -> f32;
    fn get_button(&self) -> B;
}

That's how I regularly use it:

#[derive(Component)]
pub struct CreditsWindow(f32, f32, f32, Buttons);
impl WindowValues<Buttons> for CreditsWindow {
    fn get_height(&self) -> f32 {
        self.0
    }
    fn get_left(&self) -> f32 {
        self.1
    }
    fn get_width(&self) -> f32 {
        self.2
    }
    fn get_button(&self) -> Buttons {
        self.3.clone()
    }
}

impl Default for CreditsWindow {
    fn default() -> Self {
        Self(15.0, 15.0, 0.5, Buttons::Credits)
    }
}

This is a derivable macro, I've implemented myself:

#[proc_macro_derive(TextInfo)]
pub fn derive_text_info(input: TokenStream) -> TokenStream {
    let name = parse_macro_input!(input as DeriveInput).ident;
    TokenStream::from(quote! {
        impl TextInfo for #name {
            fn get_x(&self) -> f32 {self.0}
            fn get_y(&self) -> f32 {self.1}
            fn get_name(&self) -> String {self.2.clone()}

        }
    })
}

The problem for me now is that I haven't quite figured out how to derive a generic one from my previous experience with procedural macros.

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