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Published 20 hours ago • verified publisher icon JelteF

open for a IntoBox derive?

Open extrawurst opened this issue 6 months ago • 2 comments
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It would be great to have a simple derive for Boxed newtypes to just use <MyError>.into with:

#[derive(IntoBox)]
struct BoxedError(Box<MyError>);

The specific use case is that with thiserror its easy to compose complex error types and if one inner error exceeds a certain size you naturally want to Box only that one instead of making the whole compound error type boxed, now you have to write a custom From.

This comes up a lot in thiserror:

  • https://github.com/dtolnay/thiserror/issues/57
  • https://github.com/dtolnay/thiserror/issues/90
  • https://github.com/dtolnay/thiserror/issues/302
  • https://github.com/dtolnay/thiserror/issues/415

and it keeps referencing this crate for a solution wich it does not currently supply (to my knowledge). Would you be open for such a IntoBox (or FromInner, I am open regarding the naming)?

extrawurst avatar May 03 '25 08:05 extrawurst