error: the trait core::marker::Sized is not implemented for the type std::error::Error + Sized + 'static #33201
Description
The error is not easy to understand for this code:
use std::error::Error;
use std::fmt;
#[derive(Debug, Clone)]
struct SomeError {
cause: String
}
impl fmt::Display for SomeError {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
write!(f, "SomeError")
}
}
impl Error for SomeError {
fn description(&self) -> &str {
"Some Error"
}
fn cause(&self) -> Option<&Error> {
None
}
}
#[derive(Debug, Clone)]
enum NewError {
SomeCause(Error + Sized)
}
fn main() {
let error = NewError::SomeCause(SomeError { cause: "some cause".to_string() });
println!("{:?}", error);
}(it's also in https://play.rust-lang.org/?gist=ec4209f420275037c3f652a7aeae01ff&version=stable&mode=debug)
If I understand properly, the issue is that I should have something like this instead:
enum NewError<T: Error> {
SomeCause(T)
}But the error is very misleading.