Module trackable::error [−][src]
Functionalities for implementing trackable errors and operating on those.
You can easily define your own trackable error types as follows:
#[macro_use] extern crate trackable; use trackable::error::{TrackableError, ErrorKind, ErrorKindExt}; #[derive(Debug, TrackableError)] #[trackable(error_kind = "MyErrorKind")] struct MyError(TrackableError<MyErrorKind>); impl From<std::io::Error> for MyError { fn from(f: std::io::Error) -> Self { // Any I/O errors are considered critical MyErrorKind::Critical.cause(f).into() } } #[derive(Debug, PartialEq, Eq)] enum MyErrorKind { Critical, NonCritical, } impl ErrorKind for MyErrorKind {} fn main() { // Tracks an error let error: MyError = MyErrorKind::Critical.cause("something wrong").into(); let error = track!(error); let error = track!(error, "I passed here"); assert_eq!(format!("\nError: {}", error).replace('\\', "/"), r#" Error: Critical (cause; something wrong) HISTORY: [0] at src/error.rs:27 [1] at src/error.rs:28 -- I passed here "#); // Tries to execute I/O operation let result = (|| -> Result<_, MyError> { let f = track!(std::fs::File::open("/path/to/non_existent_file") .map_err(MyError::from))?; Ok(f) })(); let error = result.err().unwrap(); let cause = error.concrete_cause::<std::io::Error>().unwrap(); assert_eq!(cause.kind(), std::io::ErrorKind::NotFound); }
TrackableError
drive macro
If it is specified (i.e., #[derive(TrackableError)]
),
the following traits will be automatically implemented in the target error type:
Trackable
Error
Display
Deref<Target = TrackableError<$error_kind>>
From<$error_kind>
From<TrackableError<$error_kind>>
From<$target_error_type> for TrackableError<$error_kind>
The default value of $error_kind
is ErrorKind
.
It can be customized by using #[trackable(error_type = "$error_kind")]
attribute.
The target error type must be a newtype (i.e., a tuple struct that has a single element) of TrackableError
.
Structs
Failed | Built-in |
Failure |
|
IoError | A variant of |
TopLevelError | An |
TrackableError | Trackable error. |
Traits
ErrorKind | This trait represents an error kind which |
ErrorKindExt | An extention of |
Type Definitions
BoxError | Boxed |
BoxErrorKind | Boxed |
History |
|
MainError | An |
TestError | An |