Hi, in my project I made a trait (CanWriteBox) that I want to implement on my struct. Even though the function signature of the write_box_of function is identical between the trait definition and the implementation, I still get a impl has stricter requirements than trait error.
Below is the code in question isolated:

use std::hash::Hash;
use std::io::{Seek, Write};
use std::marker::PhantomData;

pub trait WriteDomain: Sized {
    type Pointer;
    type Cat: Eq + Hash + Ord + Default + Clone;
    
    // ...
}

pub trait WriteCtx<Cat>
where
    Cat: Eq + Hash + Ord + Default + Clone,
{
    type Writer: Write + Seek;
    type InnerCtx<'a>: WriteCtx<Cat, Writer = Self::Writer> where Self: 'a;
    
    // ...
}

pub trait CanWriteBox: WriteDomain {
    fn write_box_of<W: WriteCtx<Self::Cat>>(
        &mut self,
        ctx: &mut W,
        write_content: impl FnOnce(&mut Self, &mut W::InnerCtx<'_>),
    );
}

struct FormatCgfx<C: Eq + Hash + Ord + Default + Clone> {
    _marker: PhantomData<C>,
}

impl<C: Eq + Hash + Ord + Default + Clone> WriteDomain for FormatCgfx<C> {
    type Pointer = u32;
    type Cat = C;
}

impl<C: Eq + Hash + Ord + Default + Clone> CanWriteBox for FormatCgfx<C> {
    fn write_box_of<W: WriteCtx<Self::Cat>>(
        &mut self,
        _ctx: &mut W,
        _write_content: impl FnOnce(&mut Self, &mut W::InnerCtx<'_>),
    ) {
        // ...
    }
}

(Playground)

I would appreciate help.

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