Ohhh, I think this is pretty much the last change to Failure I need! If I'm reading it correctly, it allows you write plain-text error messages, and then upcast them to a custom error type. This would allow combining custom error messages + error types! https://github.com/rust-lang-nursery/failure/pull/260 …
Oh wait, no there's some other things* I'd like to see too. But yeah, this is a great first step! :D * try blocks on stable, mostly. Probably also more guides because errors are a complex topic. Oh also backtraces in core. And better ecosystem adoption. Oh well.