Comment by the__alchemist
19 hours ago
What's the standard? I'm not being snarky; I'm going down the thought process of how this would work in practice.
I am on team Io Error [on std rust]", somewhat arbitrarily. If I call a lib that is on Team Anyhow, or Team Custom Error Enum, I will have to do some (Straightfoward, but a little clumsy) conversions if I want ? to work. This is complicated by being able to impl From<ErrorType1> for ErrorType2 only in one direction if you don't control the other crate. (due to the orphan rule)
By standard I meant an error type that implements std::error::Error.
EDIT: Which I assume all my dependencies have done, given that anyhow is able to consume all of them.
I specifically called out writing applications as my use case: my only objection to tptacek's note is the somewhat universal "in practice". The burden for designing errors for a library that others will use is higher, but that's far from the default/universal experience.
Many more people are going to consume libraries & not produce any of their own, and I think my experience is representative there.
There is no team io::Error. There is only one standard: https://doc.rust-lang.org/core/error/trait.Error.html