如何将anywhere错误转换为std错误

Question

我是anywhere的新手，我想知道是否有办法将anywhere错误转换为std错误

代码

fn m() {
let a: anyhow::Result<String> = Ok("".into());
n(a);
}
fn n(r: std::result::Result<String, impl std::error::Error>) {
println!("{:?}", r);
}

错误消息

error[E0277]: the trait bound `anyhow::Error: std::error::Error` is not satisfied
--> srcmain.rs:82:7
|
82 |     n(a);
|     - ^ the trait `std::error::Error` is not implemented for `anyhow::Error`
|     |
|     required by a bound introduced by this call

Answer 1

使用Deref或AsRefimpl:

match a {
Ok(v) => n(Ok::<_, &dyn std::error::Error>(v)),
Err(e) => n(Err::<_, &dyn std::error::Error>(e.as_ref())),
}
// Or
match a {
Ok(v) => n(Ok::<_, &dyn std::error::Error>(v)),
Err(e) => n(Err::<_, &dyn std::error::Error>(&*e)),
}