Trait gosh_remote::cli::ser::StdError
1.0.0 · source · pub trait StdError: Debug + Display {
// Provided methods
fn source(&self) -> Option<&(dyn Error + 'static)> { ... }
fn description(&self) -> &str { ... }
fn cause(&self) -> Option<&dyn Error> { ... }
fn provide<'a>(&'a self, demand: &mut Demand<'a>) { ... }
}Expand description
Error is a trait representing the basic expectations for error values,
i.e., values of type E in Result<T, E>.
Errors must describe themselves through the Display and Debug
traits. Error messages are typically concise lowercase sentences without
trailing punctuation:
let err = "NaN".parse::<u32>().unwrap_err();
assert_eq!(err.to_string(), "invalid digit found in string");Errors may provide cause information. Error::source() is generally
used when errors cross “abstraction boundaries”. If one module must report
an error that is caused by an error from a lower-level module, it can allow
accessing that error via Error::source(). This makes it possible for the
high-level module to provide its own errors while also revealing some of the
implementation for debugging.
Provided Methods§
1.30.0 · sourcefn source(&self) -> Option<&(dyn Error + 'static)>
fn source(&self) -> Option<&(dyn Error + 'static)>
The lower-level source of this error, if any.
Examples
use std::error::Error;
use std::fmt;
#[derive(Debug)]
struct SuperError {
source: SuperErrorSideKick,
}
impl fmt::Display for SuperError {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
write!(f, "SuperError is here!")
}
}
impl Error for SuperError {
fn source(&self) -> Option<&(dyn Error + 'static)> {
Some(&self.source)
}
}
#[derive(Debug)]
struct SuperErrorSideKick;
impl fmt::Display for SuperErrorSideKick {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
write!(f, "SuperErrorSideKick is here!")
}
}
impl Error for SuperErrorSideKick {}
fn get_super_error() -> Result<(), SuperError> {
Err(SuperError { source: SuperErrorSideKick })
}
fn main() {
match get_super_error() {
Err(e) => {
println!("Error: {e}");
println!("Caused by: {}", e.source().unwrap());
}
_ => println!("No error"),
}
}sourcefn description(&self) -> &str
fn description(&self) -> &str
if let Err(e) = "xc".parse::<u32>() {
// Print `e` itself, no need for description().
eprintln!("Error: {e}");
}sourcefn cause(&self) -> Option<&dyn Error>
fn cause(&self) -> Option<&dyn Error>
sourcefn provide<'a>(&'a self, demand: &mut Demand<'a>)
fn provide<'a>(&'a self, demand: &mut Demand<'a>)
error_generic_member_access)Provides type based access to context intended for error reports.
Used in conjunction with Demand::provide_value and Demand::provide_ref to extract
references to member variables from dyn Error trait objects.
Example
#![feature(provide_any)]
#![feature(error_generic_member_access)]
use core::fmt;
use core::any::Demand;
#[derive(Debug)]
struct MyBacktrace {
// ...
}
impl MyBacktrace {
fn new() -> MyBacktrace {
// ...
}
}
#[derive(Debug)]
struct SourceError {
// ...
}
impl fmt::Display for SourceError {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
write!(f, "Example Source Error")
}
}
impl std::error::Error for SourceError {}
#[derive(Debug)]
struct Error {
source: SourceError,
backtrace: MyBacktrace,
}
impl fmt::Display for Error {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
write!(f, "Example Error")
}
}
impl std::error::Error for Error {
fn provide<'a>(&'a self, demand: &mut Demand<'a>) {
demand
.provide_ref::<MyBacktrace>(&self.backtrace)
.provide_ref::<dyn std::error::Error + 'static>(&self.source);
}
}
fn main() {
let backtrace = MyBacktrace::new();
let source = SourceError {};
let error = Error { source, backtrace };
let dyn_error = &error as &dyn std::error::Error;
let backtrace_ref = dyn_error.request_ref::<MyBacktrace>().unwrap();
assert!(core::ptr::eq(&error.backtrace, backtrace_ref));
}Implementations§
source§impl<'a> dyn Error + 'a
impl<'a> dyn Error + 'a
sourcepub fn request_ref<T>(&'a self) -> Option<&'a T>where
T: 'static + ?Sized,
🔬This is a nightly-only experimental API. (error_generic_member_access)
pub fn request_ref<T>(&'a self) -> Option<&'a T>where
T: 'static + ?Sized,
error_generic_member_access)Request a reference of type T as context about this error.
sourcepub fn request_value<T>(&'a self) -> Option<T>where
T: 'static,
🔬This is a nightly-only experimental API. (error_generic_member_access)
pub fn request_value<T>(&'a self) -> Option<T>where
T: 'static,
error_generic_member_access)Request a value of type T as context about this error.
source§impl dyn Error + 'static
impl dyn Error + 'static
1.3.0 · sourcepub fn is<T>(&self) -> boolwhere
T: Error + 'static,
pub fn is<T>(&self) -> boolwhere
T: Error + 'static,
Returns true if the inner type is the same as T.
1.3.0 · sourcepub fn downcast_ref<T>(&self) -> Option<&T>where
T: Error + 'static,
pub fn downcast_ref<T>(&self) -> Option<&T>where
T: Error + 'static,
Returns some reference to the inner value if it is of type T, or
None if it isn’t.
1.3.0 · sourcepub fn downcast_mut<T>(&mut self) -> Option<&mut T>where
T: Error + 'static,
pub fn downcast_mut<T>(&mut self) -> Option<&mut T>where
T: Error + 'static,
Returns some mutable reference to the inner value if it is of type T, or
None if it isn’t.
source§impl dyn Error + Send + 'static
impl dyn Error + Send + 'static
1.3.0 · sourcepub fn is<T>(&self) -> boolwhere
T: Error + 'static,
pub fn is<T>(&self) -> boolwhere
T: Error + 'static,
Forwards to the method defined on the type dyn Error.
1.3.0 · sourcepub fn downcast_ref<T>(&self) -> Option<&T>where
T: Error + 'static,
pub fn downcast_ref<T>(&self) -> Option<&T>where
T: Error + 'static,
Forwards to the method defined on the type dyn Error.
1.3.0 · sourcepub fn downcast_mut<T>(&mut self) -> Option<&mut T>where
T: Error + 'static,
pub fn downcast_mut<T>(&mut self) -> Option<&mut T>where
T: Error + 'static,
Forwards to the method defined on the type dyn Error.
sourcepub fn request_ref<T>(&self) -> Option<&T>where
T: 'static + ?Sized,
🔬This is a nightly-only experimental API. (error_generic_member_access)
pub fn request_ref<T>(&self) -> Option<&T>where
T: 'static + ?Sized,
error_generic_member_access)Request a reference of type T as context about this error.
sourcepub fn request_value<T>(&self) -> Option<T>where
T: 'static,
🔬This is a nightly-only experimental API. (error_generic_member_access)
pub fn request_value<T>(&self) -> Option<T>where
T: 'static,
error_generic_member_access)Request a value of type T as context about this error.
source§impl dyn Error + Sync + Send + 'static
impl dyn Error + Sync + Send + 'static
1.3.0 · sourcepub fn is<T>(&self) -> boolwhere
T: Error + 'static,
pub fn is<T>(&self) -> boolwhere
T: Error + 'static,
Forwards to the method defined on the type dyn Error.
1.3.0 · sourcepub fn downcast_ref<T>(&self) -> Option<&T>where
T: Error + 'static,
pub fn downcast_ref<T>(&self) -> Option<&T>where
T: Error + 'static,
Forwards to the method defined on the type dyn Error.
1.3.0 · sourcepub fn downcast_mut<T>(&mut self) -> Option<&mut T>where
T: Error + 'static,
pub fn downcast_mut<T>(&mut self) -> Option<&mut T>where
T: Error + 'static,
Forwards to the method defined on the type dyn Error.
sourcepub fn request_ref<T>(&self) -> Option<&T>where
T: 'static + ?Sized,
🔬This is a nightly-only experimental API. (error_generic_member_access)
pub fn request_ref<T>(&self) -> Option<&T>where
T: 'static + ?Sized,
error_generic_member_access)Request a reference of type T as context about this error.
sourcepub fn request_value<T>(&self) -> Option<T>where
T: 'static,
🔬This is a nightly-only experimental API. (error_generic_member_access)
pub fn request_value<T>(&self) -> Option<T>where
T: 'static,
error_generic_member_access)Request a value of type T as context about this error.
source§impl dyn Error + 'static
impl dyn Error + 'static
sourcepub fn sources(&self) -> Source<'_>
🔬This is a nightly-only experimental API. (error_iter)
pub fn sources(&self) -> Source<'_>
error_iter)Returns an iterator starting with the current error and continuing with
recursively calling Error::source.
If you want to omit the current error and only use its sources,
use skip(1).
Examples
#![feature(error_iter)]
use std::error::Error;
use std::fmt;
#[derive(Debug)]
struct A;
#[derive(Debug)]
struct B(Option<Box<dyn Error + 'static>>);
impl fmt::Display for A {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
write!(f, "A")
}
}
impl fmt::Display for B {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
write!(f, "B")
}
}
impl Error for A {}
impl Error for B {
fn source(&self) -> Option<&(dyn Error + 'static)> {
self.0.as_ref().map(|e| e.as_ref())
}
}
let b = B(Some(Box::new(A)));
// let err : Box<Error> = b.into(); // or
let err = &b as &(dyn Error);
let mut iter = err.sources();
assert_eq!("B".to_string(), iter.next().unwrap().to_string());
assert_eq!("A".to_string(), iter.next().unwrap().to_string());
assert!(iter.next().is_none());
assert!(iter.next().is_none());Trait Implementations§
1.6.0 · source§impl From<&str> for Box<dyn Error + 'static, Global>
impl From<&str> for Box<dyn Error + 'static, Global>
source§impl<'a> From<&str> for Box<dyn Error + Sync + Send + 'a, Global>
impl<'a> From<&str> for Box<dyn Error + Sync + Send + 'a, Global>
1.22.0 · source§impl<'a> From<Cow<'a, str>> for Box<dyn Error + 'static, Global>
impl<'a> From<Cow<'a, str>> for Box<dyn Error + 'static, Global>
1.22.0 · source§impl<'a, 'b> From<Cow<'b, str>> for Box<dyn Error + Sync + Send + 'a, Global>
impl<'a, 'b> From<Cow<'b, str>> for Box<dyn Error + Sync + Send + 'a, Global>
source§fn from(err: Cow<'b, str>) -> Box<dyn Error + Sync + Send + 'a, Global>
fn from(err: Cow<'b, str>) -> Box<dyn Error + Sync + Send + 'a, Global>
Converts a Cow into a box of dyn Error + Send + Sync.
Examples
use std::error::Error;
use std::mem;
use std::borrow::Cow;
let a_cow_str_error = Cow::from("a str error");
let a_boxed_error = Box::<dyn Error + Send + Sync>::from(a_cow_str_error);
assert!(
mem::size_of::<Box<dyn Error + Send + Sync>>() == mem::size_of_val(&a_boxed_error))source§impl<'a, E> From<E> for Box<dyn Error + 'a, Global>where
E: Error + 'a,
impl<'a, E> From<E> for Box<dyn Error + 'a, Global>where
E: Error + 'a,
source§fn from(err: E) -> Box<dyn Error + 'a, Global>
fn from(err: E) -> Box<dyn Error + 'a, Global>
Converts a type of Error into a box of dyn Error.
Examples
use std::error::Error;
use std::fmt;
use std::mem;
#[derive(Debug)]
struct AnError;
impl fmt::Display for AnError {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
write!(f, "An error")
}
}
impl Error for AnError {}
let an_error = AnError;
assert!(0 == mem::size_of_val(&an_error));
let a_boxed_error = Box::<dyn Error>::from(an_error);
assert!(mem::size_of::<Box<dyn Error>>() == mem::size_of_val(&a_boxed_error))source§impl<'a, E> From<E> for Box<dyn Error + Sync + Send + 'a, Global>where
E: Error + Send + Sync + 'a,
impl<'a, E> From<E> for Box<dyn Error + Sync + Send + 'a, Global>where
E: Error + Send + Sync + 'a,
source§fn from(err: E) -> Box<dyn Error + Sync + Send + 'a, Global>
fn from(err: E) -> Box<dyn Error + Sync + Send + 'a, Global>
Converts a type of Error + Send + Sync into a box of
dyn Error + Send + Sync.
Examples
use std::error::Error;
use std::fmt;
use std::mem;
#[derive(Debug)]
struct AnError;
impl fmt::Display for AnError {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
write!(f, "An error")
}
}
impl Error for AnError {}
unsafe impl Send for AnError {}
unsafe impl Sync for AnError {}
let an_error = AnError;
assert!(0 == mem::size_of_val(&an_error));
let a_boxed_error = Box::<dyn Error + Send + Sync>::from(an_error);
assert!(
mem::size_of::<Box<dyn Error + Send + Sync>>() == mem::size_of_val(&a_boxed_error))1.6.0 · source§impl From<String> for Box<dyn Error + 'static, Global>
impl From<String> for Box<dyn Error + 'static, Global>
source§impl From<String> for Box<dyn Error + Sync + Send + 'static, Global>
impl From<String> for Box<dyn Error + Sync + Send + 'static, Global>
source§fn from(err: String) -> Box<dyn Error + Sync + Send + 'static, Global>
fn from(err: String) -> Box<dyn Error + Sync + Send + 'static, Global>
Converts a String into a box of dyn Error + Send + Sync.
Examples
use std::error::Error;
use std::mem;
let a_string_error = "a string error".to_string();
let a_boxed_error = Box::<dyn Error + Send + Sync>::from(a_string_error);
assert!(
mem::size_of::<Box<dyn Error + Send + Sync>>() == mem::size_of_val(&a_boxed_error))Implementors§
impl !Error for &str
impl Error for webpki::error::Error
Requires the std feature.
impl Error for Infallible
impl Error for VarError
impl Error for std::sync::mpsc::RecvTimeoutError
impl Error for std::sync::mpsc::TryRecvError
impl Error for time::ParseError
impl Error for ExtensionRejection
impl Error for FormRejection
impl Error for JsonRejection
impl Error for MatchedPathRejection
impl Error for PathRejection
impl Error for QueryRejection
impl Error for RoundingError
impl Error for clap::parser::error::MatchesError
impl Error for clap::parser::error::MatchesError
impl Error for crossbeam_channel::err::RecvTimeoutError
impl Error for crossbeam_channel::err::TryRecvError
impl Error for FromHexError
impl Error for nix::Error
impl Error for nix::Error
impl Error for nix::errno::consts::Errno
impl Error for nix::errno::consts::Errno
impl Error for nix::errno::consts::Errno
impl Error for BernoulliError
impl Error for WeightedError
impl Error for AnyDelimiterCodecError
impl Error for LinesCodecError
impl Error for TryAcquireError
impl Error for tokio::sync::broadcast::error::RecvError
impl Error for tokio::sync::broadcast::error::TryRecvError
impl Error for tokio::sync::mpsc::error::TryRecvError
impl Error for tokio::sync::oneshot::error::TryRecvError
impl Error for url::parser::ParseError
impl Error for rand_distr::binomial::Error
impl Error for rand_distr::cauchy::Error
impl Error for rand_distr::dirichlet::Error
impl Error for rand_distr::exponential::Error
impl Error for rand_distr::frechet::Error
impl Error for BetaError
impl Error for ChiSquaredError
impl Error for rand_distr::gamma::Error
impl Error for FisherFError
impl Error for rand_distr::geometric::Error
impl Error for rand_distr::gumbel::Error
impl Error for rand_distr::hypergeometric::Error
impl Error for rand_distr::inverse_gaussian::Error
impl Error for rand_distr::normal::Error
impl Error for rand_distr::normal_inverse_gaussian::Error
impl Error for rand_distr::pareto::Error
impl Error for PertError
impl Error for rand_distr::poisson::Error
impl Error for rand_distr::skew_normal::Error
impl Error for TriangularError
impl Error for rand_distr::weibull::Error
impl Error for ZetaError
impl Error for ZipfError
impl Error for !
impl Error for gosh_remote::cli::de::value::Error
impl Error for webpki::name::dns_name::InvalidDnsNameError
Requires the std feature.
impl Error for TryReserveError
impl Error for FromVecWithNulError
impl Error for IntoStringError
impl Error for NulError
impl Error for alloc::string::FromUtf8Error
impl Error for FromUtf16Error
impl Error for LayoutError
impl Error for AllocError
impl Error for TryFromSliceError
impl Error for BorrowError
impl Error for BorrowMutError
impl Error for CharTryFromError
impl Error for ParseCharError
impl Error for DecodeUtf16Error
impl Error for TryFromCharError
impl Error for FromBytesUntilNulError
impl Error for FromBytesWithNulError
impl Error for core::fmt::Error
impl Error for ParseFloatError
impl Error for ParseIntError
impl Error for TryFromIntError
impl Error for ParseBoolError
impl Error for core::str::error::Utf8Error
impl Error for TryFromFloatSecsError
impl Error for JoinPathsError
impl Error for WriterPanicked
impl Error for std::io::error::Error
impl Error for std::net::parser::AddrParseError
impl Error for StripPrefixError
impl Error for ExitStatusError
impl Error for std::sync::mpsc::RecvError
impl Error for AccessError
impl Error for SystemTimeError
impl Error for OutOfRangeError
impl Error for FailedToDeserializePathParams
impl Error for FailedToDeserializeQueryString
impl Error for InvalidFormContentType
impl Error for InvalidJsonBody
impl Error for axum::extract::rejection::LengthRequired
impl Error for MatchedPathMissing
impl Error for axum::extract::rejection::MissingExtension
impl Error for MissingJsonContentType
impl Error for MissingPathParams
impl Error for axum::extract::rejection::PayloadTooLarge
impl Error for chrono::format::ParseError
impl Error for ParseWeekdayError
impl Error for clap::error::Error
impl Error for crossbeam_channel::err::RecvError
impl Error for SelectTimeoutError
impl Error for TrySelectError
impl Error for CompressError
impl Error for DecompressError
impl Error for getrandom::error::Error
impl Error for h2::error::Error
impl Error for RenderError
impl Error for TemplateError
impl Error for headers_core::Error
impl Error for LengthLimitError
impl Error for http::error::Error
impl Error for InvalidHeaderName
impl Error for InvalidHeaderValue
impl Error for ToStrError
impl Error for InvalidMethod
impl Error for InvalidStatusCode
impl Error for InvalidUri
impl Error for InvalidUriParts
impl Error for PrefixLenError
impl Error for ipnet::parser::AddrParseError
impl Error for log::ParseLevelError
impl Error for SetLoggerError
impl Error for FromStrError
impl Error for ClearEnvError
impl Error for ReadError
impl Error for reqwest::error::Error
impl Error for serde_json::error::Error
impl Error for PathPersistError
impl Error for PersistError
impl Error for tera::errors::Error
impl Error for LengthDelimitedCodecError
impl Error for tokio::net::tcp::split_owned::ReuniteError
impl Error for tokio::net::unix::split_owned::ReuniteError
impl Error for TryCurrentError
impl Error for JoinError
impl Error for AcquireError
impl Error for tokio::sync::mutex::TryLockError
impl Error for tokio::sync::oneshot::error::RecvError
impl Error for tokio::sync::watch::error::RecvError
impl Error for Elapsed
impl Error for tokio::time::error::Error
impl Error for SetGlobalDefaultError
impl Error for tracing_core::metadata::ParseLevelError
impl Error for ParseLevelFilterError
impl Error for warp::error::Error
impl Error for BodyDeserializeError
impl Error for CorsForbidden
impl Error for warp::filters::ext::MissingExtension
impl Error for MissingConnectionUpgrade
impl Error for InvalidHeader
impl Error for InvalidQuery
impl Error for warp::reject::LengthRequired
impl Error for MethodNotAllowed
impl Error for MissingCookie
impl Error for MissingHeader
impl Error for warp::reject::PayloadTooLarge
impl Error for UnsupportedMediaType
impl Error for WsError
impl Error for rand_core::error::Error
impl Error for Aborted
impl Error for BodyAlreadyExtracted
impl Error for BytesRejection
impl Error for Canceled
impl Error for CapacityError
impl Error for CaseFoldError
impl Error for Closed
impl Error for ColorChoiceParseError
impl Error for ColorError
impl Error for CommandError
impl Error for ComponentRange
impl Error for ConfigError
impl Error for ConversionRange
impl Error for DatetimeParseError
impl Error for DecodeError
impl Error for DecodeError
impl Error for DecodeError
impl Error for DecodeSliceError
impl Error for DifferentVariant
impl Error for EncodeSliceError
impl Error for EncodingError
impl Error for Errno
impl Error for Error
impl Error for Error
impl Error for Error
impl Error for Error
impl Error for Error
impl Error for Error
impl Error for Error
impl Error for Error
impl Error for Error
impl Error for Error
impl Error for Error
impl Error for Error
impl Error for Error
impl Error for Error
impl Error for Error
impl Error for Error
impl Error for Error
impl Error for Error
impl Error for Error
impl Error for Error
impl Error for Error
impl Error for Error
impl Error for Error
impl Error for Error
impl Error for Errors
impl Error for ExtensionsAlreadyExtracted
impl Error for FailedToBufferBody
impl Error for FloatIsNan
impl Error for FromUtf8Error
impl Error for GetTimezoneError
impl Error for GlobError
impl Error for HeadersAlreadyExtracted
impl Error for InsertError
impl Error for InvalidBufferSize
impl Error for InvalidDnsNameError
impl Error for InvalidLength
impl Error for InvalidNameError
impl Error for InvalidOutputSize
impl Error for InvalidPatternError
impl Error for InvalidUtf8
impl Error for InvalidVariant
impl Error for MatchError
impl Error for NoError
impl Error for None
impl Error for ParseAlphabetError
impl Error for ParseAlphabetError
impl Error for ParseColorError
impl Error for ParseQuantityError
impl Error for ParseSizeError
impl Error for ProcError
impl Error for ProtocolError
impl Error for RequestAlreadyExtracted
impl Error for RequestPartsAlreadyExtracted
impl Error for SendError
impl Error for ServiceError
impl Error for SignError
impl Error for SpawnError
impl Error for StrSimError
impl Error for StringRejection
impl Error for ThreadPoolBuildError
impl Error for TlsError
impl Error for TryRecvError
impl Error for UnicodeWordError
impl Error for UrlError
impl Error for Utf8Error
impl<'a> Error for BufReadDecoderError<'a>
impl<'a> Error for DecodeError<'a>
impl<'a, K, V> Error for alloc::collections::btree::map::entry::OccupiedError<'a, K, V, Global>where
K: Debug + Ord,
V: Debug,
impl<'a, K, V> Error for std::collections::hash::map::OccupiedError<'a, K, V>where
K: Debug,
V: Debug,
impl<'a, T> Error for &'a Twhere
T: Error + ?Sized,
impl<E> Error for Err<E>where
E: Debug,
impl<E> Error for ParseNotNanError<E>where
E: Debug + Error + 'static,
impl<F> Error for clap::error::Error<F>where
F: ErrorFormatter,
impl<I> Error for ExactlyOneError<I>where
I: Iterator + Debug,
<I as Iterator>::Item: Debug,
impl<I> Error for Error<I>where
I: Debug + Display,
impl<I> Error for VerboseError<I>where
I: Debug + Display,
impl<L, R> Error for Either<L, R>where
L: Error,
R: Error,
Either implements Error if both L and R implement it.