Trait error_trace::ErrorTrace

pub trait ErrorTrace: Error {
    // Required method
    fn trace(&self) -> ErrorTraceFormatter<'_, '_>;
}

Allows one to write an error and all of its dependencies.

Example

use std::error::Error;
use std::fmt::{Display, Formatter, Result as FResult};

use error_trace::ErrorTrace as _;

#[derive(Debug)]
struct SomeError {
    msg: String,
}
impl Display for SomeError {
    fn fmt(&self, f: &mut Formatter<'_>) -> FResult { write!(f, "{}", self.msg) }
}
impl Error for SomeError {}

#[derive(Debug)]
struct HigherError {
    msg:   String,
    child: SomeError,
}
impl Display for HigherError {
    fn fmt(&self, f: &mut Formatter<'_>) -> FResult { write!(f, "{}", self.msg) }
}
impl Error for HigherError {
    fn source(&self) -> Option<&(dyn 'static + Error)> { Some(&self.child) }
}



let err = HigherError {
    msg:   "Oh no, something went wrong!".into(),
    child: SomeError { msg: "A specific reason".into() },
};
assert_eq!(
    err.trace().to_string(),
    r#"Oh no, something went wrong!

Caused by:
 o A specific reason

"#
);

Required Methods

fn trace(&self) -> ErrorTraceFormatter<'_, '_>

Returns a formatter for showing this Error and all its sources.

This function can be used similarly to Path::display(), since its result implements both Debug and Display.

Returns

A new ErrorTraceFormatter that implements Debug and Display.

Example

use error_trace::ErrorTrace as _;

let err = HigherError { msg: "Oh no, something went wrong!".into(), child: SomeError { msg: "A specific reason".into() } };
assert_eq!(err.trace().to_string(), r#"Oh no, something went wrong!

Caused by:
 o A specific reason

"#);

Implementors

impl<T: ?Sized + Error> ErrorTrace for T