Seems not possible to override and proxy the downcast_ref of dyn std::error::Error to the inner error, so downcast will not work once Exn is wrapped into a dyn Error.

Seems not possible to override and proxy the downcast_ref of dyn std::error::Error to the inner error, so downcast will not work once Exn is wrapped into a dyn Error.

anyhow does the same--disallowing downcast once boxed into a dyn std::error::Error.

Seems not possible to override and proxy the downcast_ref of dyn std::error::Error to the inner error, so downcast will not work once Exn is wrapped into a dyn Error.

anyhow does the same--disallowing downcast once boxed into a dyn std::error::Error.

Based on our API, one can first downcast the Error to Frame and then call Frame::error to fetch the internal error and call downcast on that error instead?

Based on our API, one can first downcast the Error to Frame and then call Frame::error to fetch the internal error and call downcast on that error instead?

Yes.

Perhaps add a changelog entry?

@andylokandy What if we release a 0.3.0 and handle other issues later?