Trait StdError 

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, request: &mut Request<'a>) { ... }
}

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");

Error source

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.

In error types that wrap an underlying error, the underlying error should be either returned by the outer error’s Error::source(), or rendered by the outer error’s Display implementation, but not both.

Example

Implementing the Error trait only requires that Debug and Display are implemented too.

use std::error::Error;
use std::fmt;
use std::path::PathBuf;

#[derive(Debug)]
struct ReadConfigError {
    path: PathBuf
}

impl fmt::Display for ReadConfigError {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        let path = self.path.display();
        write!(f, "unable to read configuration at {path}")
    }
}

impl Error for ReadConfigError {}

Provided Methods

fn source(&self) -> Option<&(dyn Error + 'static)>

Returns 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"),
    }
}

fn description(&self) -> &str

👎Deprecated since 1.42.0:

use the Display impl or to_string()

if let Err(e) = "xc".parse::<u32>() {
    // Print `e` itself, no need for description().
    eprintln!("Error: {e}");
}

fn cause(&self) -> Option<&dyn Error>

👎Deprecated since 1.33.0:

replaced by Error::source, which can support downcasting

fn provide<'a>(&'a self, request: &mut Request<'a>)

🔬This is a nightly-only experimental API. (error_generic_member_access)

Provides type-based access to context intended for error reports.

Used in conjunction with Request::provide_value and Request::provide_ref to extract references to member variables from dyn Error trait objects.

Example

#![feature(error_generic_member_access)]
use core::fmt;
use core::error::{request_ref, Request};

#[derive(Debug)]
enum MyLittleTeaPot {
    Empty,
}

#[derive(Debug)]
struct MyBacktrace {
    // ...
}

impl MyBacktrace {
    fn new() -> MyBacktrace {
        // ...
    }
}

#[derive(Debug)]
struct Error {
    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, request: &mut Request<'a>) {
        request
            .provide_ref::<MyBacktrace>(&self.backtrace);
    }
}

fn main() {
    let backtrace = MyBacktrace::new();
    let error = Error { backtrace };
    let dyn_error = &error as &dyn std::error::Error;
    let backtrace_ref = request_ref::<MyBacktrace>(dyn_error).unwrap();

    assert!(core::ptr::eq(&error.backtrace, backtrace_ref));
    assert!(request_ref::<MyLittleTeaPot>(dyn_error).is_none());
}

Delegating Impls

Warning: We recommend implementors avoid delegating implementations of provide to source error implementations.

This method should expose context from the current piece of the source chain only, not from sources that are exposed in the chain of sources. Delegating provide implementations cause the same context to be provided by multiple errors in the chain of sources which can cause unintended duplication of information in error reports or require heuristics to deduplicate.

In other words, the following implementation pattern for provide is discouraged and should not be used for Error types exposed in public APIs to third parties.

struct MyError {
    source: Error,
}

impl std::error::Error for MyError {
    fn source(&self) -> Option<&(dyn std::error::Error + 'static)> {
        Some(&self.source)
    }

    fn provide<'a>(&'a self, request: &mut Request<'a>) {
        self.source.provide(request) // <--- Discouraged
    }
}

Implementations

impl dyn Error

pub fn is<T>(&self) -> bool

where T: Error + 'static,

Returns true if the inner type is the same as T.

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.

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.

impl dyn Error + Send

pub fn is<T>(&self) -> bool

where T: Error + 'static,

Forwards to the method defined on the type dyn Error.

pub fn downcast_ref<T>(&self) -> Option<&T>

where T: Error + 'static,

Forwards to the method defined on the type dyn Error.

pub fn downcast_mut<T>(&mut self) -> Option<&mut T>

where T: Error + 'static,

Forwards to the method defined on the type dyn Error.

impl dyn Error + Send + Sync

pub fn is<T>(&self) -> bool

where T: Error + 'static,

Forwards to the method defined on the type dyn Error.

pub fn downcast_ref<T>(&self) -> Option<&T>

where T: Error + 'static,

Forwards to the method defined on the type dyn Error.

pub fn downcast_mut<T>(&mut self) -> Option<&mut T>

where T: Error + 'static,

Forwards to the method defined on the type dyn Error.

impl dyn Error

pub fn sources(&self) -> Source<'_>

🔬This is a nightly-only experimental API. (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());

impl dyn Error

pub fn downcast<T>(self: Box<dyn Error>) -> Result<Box<T>, Box<dyn Error>>

where T: Error + 'static,

Attempts to downcast the box to a concrete type.

impl dyn Error + Send

pub fn downcast<T>( self: Box<dyn Error + Send>, ) -> Result<Box<T>, Box<dyn Error + Send>>

where T: Error + 'static,

Attempts to downcast the box to a concrete type.

impl dyn Error + Send + Sync

pub fn downcast<T>( self: Box<dyn Error + Send + Sync>, ) -> Result<Box<T>, Box<dyn Error + Send + Sync>>

where T: Error + 'static,

Attempts to downcast the box to a concrete type.

Trait Implementations

impl<'a> From<&str> for Box<dyn Error + Send + Sync + 'a>

Available on non-no_global_oom_handling only.

fn from(err: &str) -> Box<dyn Error + Send + Sync + 'a>

Converts a str into a box of dyn Error + Send + Sync.

Examples

use std::error::Error;

let a_str_error = "a str error";
let a_boxed_error = Box::<dyn Error + Send + Sync>::from(a_str_error);
assert!(
    size_of::<Box<dyn Error + Send + Sync>>() == size_of_val(&a_boxed_error))

impl<'a> From<&str> for Box<dyn Error + 'a>

Available on non-no_global_oom_handling only.

fn from(err: &str) -> Box<dyn Error + 'a>

Converts a str into a box of dyn Error.

Examples

use std::error::Error;

let a_str_error = "a str error";
let a_boxed_error = Box::<dyn Error>::from(a_str_error);
assert!(size_of::<Box<dyn Error>>() == size_of_val(&a_boxed_error))

impl<'a, 'b> From<Cow<'b, str>> for Box<dyn Error + Send + Sync + 'a>

Available on non-no_global_oom_handling only.

fn from(err: Cow<'b, str>) -> Box<dyn Error + Send + Sync + 'a>

Converts a Cow into a box of dyn Error + Send + Sync.

Examples

use std::error::Error;
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!(
    size_of::<Box<dyn Error + Send + Sync>>() == size_of_val(&a_boxed_error))

impl<'a, 'b> From<Cow<'b, str>> for Box<dyn Error + 'a>

Available on non-no_global_oom_handling only.

fn from(err: Cow<'b, str>) -> Box<dyn Error + 'a>

Converts a Cow into a box of dyn Error.

Examples

use std::error::Error;
use std::borrow::Cow;

let a_cow_str_error = Cow::from("a str error");
let a_boxed_error = Box::<dyn Error>::from(a_cow_str_error);
assert!(size_of::<Box<dyn Error>>() == size_of_val(&a_boxed_error))

impl<'a, E> From<E> for Box<dyn Error + 'a>

where E: Error + 'a,

Available on non-no_global_oom_handling only.

fn from(err: E) -> Box<dyn Error + 'a>

Converts a type of Error into a box of dyn Error.

Examples

use std::error::Error;
use std::fmt;

#[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 == size_of_val(&an_error));
let a_boxed_error = Box::<dyn Error>::from(an_error);
assert!(size_of::<Box<dyn Error>>() == size_of_val(&a_boxed_error))

impl<'a, E> From<E> for Box<dyn Error + Send + Sync + 'a>

where E: Error + Send + Sync + 'a,

Available on non-no_global_oom_handling only.

fn from(err: E) -> Box<dyn Error + Send + Sync + 'a>

Converts a type of Error + Send + Sync into a box of dyn Error + Send + Sync.

Examples

use std::error::Error;
use std::fmt;

#[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 == size_of_val(&an_error));
let a_boxed_error = Box::<dyn Error + Send + Sync>::from(an_error);
assert!(
    size_of::<Box<dyn Error + Send + Sync>>() == size_of_val(&a_boxed_error))

impl From<Error> for Box<dyn Error + Send + Sync>

fn from(error: Error) -> Box<dyn Error + Send + Sync>

Converts to this type from the input type.

impl From<Error> for Box<dyn Error + Send>

fn from(error: Error) -> Box<dyn Error + Send>

Converts to this type from the input type.

impl From<Error> for Box<dyn Error>

fn from(error: Error) -> Box<dyn Error>

Converts to this type from the input type.

impl<'a> From<String> for Box<dyn Error + Send + Sync + 'a>

Available on non-no_global_oom_handling only.

fn from(err: String) -> Box<dyn Error + Send + Sync + 'a>

Converts a String into a box of dyn Error + Send + Sync.

Examples

use std::error::Error;

let a_string_error = "a string error".to_string();
let a_boxed_error = Box::<dyn Error + Send + Sync>::from(a_string_error);
assert!(
    size_of::<Box<dyn Error + Send + Sync>>() == size_of_val(&a_boxed_error))

impl<'a> From<String> for Box<dyn Error + 'a>

Available on non-no_global_oom_handling only.

fn from(str_err: String) -> Box<dyn Error + 'a>

Converts a String into a box of dyn Error.

Examples

use std::error::Error;

let a_string_error = "a string error".to_string();
let a_boxed_error = Box::<dyn Error>::from(a_string_error);
assert!(size_of::<Box<dyn Error>>() == size_of_val(&a_boxed_error))

impl Value for dyn Error

Available on crate feature std only.

fn record(&self, key: &Field, visitor: &mut dyn Visit)

Visits this value with the given Visitor.

impl Value for dyn Error + Send

Available on crate feature std only.

fn record(&self, key: &Field, visitor: &mut dyn Visit)

Visits this value with the given Visitor.

impl Value for dyn Error + Sync

Available on crate feature std only.

fn record(&self, key: &Field, visitor: &mut dyn Visit)

Visits this value with the given Visitor.

impl Value for dyn Error + Send + Sync

Available on crate feature std only.

fn record(&self, key: &Field, visitor: &mut dyn Visit)

Visits this value with the given Visitor.

Dyn Compatibility

This trait is dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety".

Implementors

impl !Error for &str

impl Error for !

impl Error for ASN1Error

Available on crate feature std only.

impl Error for Aborted

Available on crate feature std only.

impl Error for AccessError

impl Error for AcquireError

impl Error for core::net::parser::AddrParseError

impl Error for ipnet::parser::AddrParseError

impl Error for AddrParseError

Available on crate feature std only.

impl Error for AllocError

impl Error for AnyDelimiterCodecError

impl Error for AttrError

impl Error for BernoulliError

Available on crate feature std only.

impl Error for BindError

impl Error for BlockError

impl Error for BorrowError

impl Error for BorrowMutError

impl Error for BoxErrorWrapper

impl Error for BuildError

Available on crate feature std only.

impl Error for BuildError

Available on crate feature std only.

impl Error for BuildError

Available on crate feature std only.

impl Error for BuildError

Available on crate feature std only.

impl Error for BuildError

Available on crate feature std only.

impl Error for BuilderError

impl Error for CacheError

Available on crate feature std only.

impl Error for CalendarError

impl Error for CalibrightError

impl Error for Canceled

Available on crate feature std only.

impl Error for CapacityOverflowError

Available on crate feature std only.

impl Error for CaseFoldError

Available on crate feature std only.

impl Error for CharTryFromError

impl Error for ClearEnvError

impl Error for Code

impl Error for CommandError

impl Error for ComponentRange

impl Error for ConfigurationError

impl Error for ConnectError

impl Error for ConnectError

Available on crate feature std only.

impl Error for ConnectionError

impl Error for ConversionRange

impl Error for DataError

impl Error for DateAddError

impl Error for DateError

impl Error for DateFromFieldsError

impl Error for DateNewError

impl Error for DateTimeFormatterLoadError

impl Error for DatetimeParseError

impl Error for DeError

impl Error for DeError

impl Error for DecodeError

Available on crate features std only.

impl Error for DecodeError

Available on crate feature std only.

impl Error for DecodeSliceError

Available on crate features std only.

impl Error for DecodeUtf16Error

impl Error for DerConstraint

Available on crate feature std only.

impl Error for DeserializeError

Available on crate feature std only.

impl Error for DifferentVariant

impl Error for DisplayParsingError

Available on crate feature std only.

impl Error for EarlyDataError

Available on crate feature std only.

impl Error for Elapsed

impl Error for Elapsed

impl Error for EncodeError

Available on crate feature std only.

impl Error for EncodeSliceError

Available on crate features std only.

impl Error for EncodingError

impl Error for EncryptError

Available on crate feature std only.

impl Error for EnterError

impl Error for Errno

Available on error_in_core or crate feature std only.

impl Error for Errno

impl Error for Errno

impl Error for core::fmt::Error

impl Error for core::io::error::Error

impl Error for serde_core::de::value::Error

Available on crate feature std only.

impl Error for Error

impl Error for Error

impl Error for Error

impl Error for Error

Available on crate feature std only.

impl Error for Error

Available on crate feature std only.

impl Error for Error

Available on crate feature std only.

impl Error for Error

Available on crate feature std only.

impl Error for Error

impl Error for Error

impl Error for Error

impl Error for Error

impl Error for serde_json::error::Error

impl Error for Error

impl Error for Error

impl Error for Error

impl Error for Error

impl Error for syn::error::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 rand_core::error::Error

Available on crate feature std only.

impl Error for getrandom::error::Error

impl Error for Error

impl Error for Error

impl Error for Error

impl Error for Error

impl Error for Error

Available on crate feature std only.

impl Error for Error

Available on crate feature std only.

impl Error for Error

Available on crate feature std only.

impl Error for Error

Available on crate feature std only.

impl Error for Error

Available on crate feature std only.

impl Error for Error

Available on crate feature std only.

impl Error for Error

Available on crate feature std only.

impl Error for Error

impl Error for uuid::error::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

Available on crate feature std only.

impl Error for Error

Available on crate feature std only.

impl Error for Error

Available on crate feature std only.

impl Error for Error

impl Error for Error

Available on crate feature std only.

impl Error for Error

Available on crate feature std only.

impl Error for Error

Available on crate feature std only.

impl Error for Error

Available on crate feature std only.

impl Error for Error

Available on crate feature std only.

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 i3status_rs::errors::Error

impl Error for ErrorKind

Available on crate feature std only.

impl Error for bincode::error::ErrorKind

impl Error for ErrorStack

impl Error for Errors

Available on crate feature std only.

impl Error for proc_macro::EscapeError

impl Error for EscapeError

impl Error for ExitStatusError

impl Error for ExpandError

impl Error for Format

impl Error for FormatError

impl Error for FromBytesUntilNulError

impl Error for FromBytesWithNulError

impl Error for FromHexError

Available on crate feature std only.

impl Error for FromUtf8Error

impl Error for FromUtf16Error

impl Error for FromVecWithNulError

impl Error for GenError

Available on crate feature std only.

impl Error for GetDisjointMutError

impl Error for GetTimezoneError

impl Error for GlobError

impl Error for GroupInfoError

Available on crate feature std only.

impl Error for I32CastError

impl Error for IdsExhausted

Available on crate feature std only.

impl Error for IllFormedError

impl Error for Infallible

impl Error for IntoStringError

impl Error for InvalidBackoff

impl Error for InvalidBufferSize

Available on crate feature std only.

impl Error for InvalidDnsNameError

Available on crate feature std only.

impl Error for InvalidEncodingError

impl Error for InvalidFormatDescription

impl Error for InvalidHeaderName

impl Error for InvalidHeaderValue

impl Error for InvalidLength

Available on crate feature std only.

impl Error for InvalidLengthError

impl Error for InvalidMethod

impl Error for InvalidNameError

impl Error for InvalidOutputSize

Available on crate feature std only.

impl Error for InvalidStatusCode

impl Error for InvalidUri

impl Error for InvalidUriParts

impl Error for InvalidVariant

impl Error for JoinError

impl Error for JoinPathsError

impl Error for KeyingMaterialExporterError

impl Error for LayoutError

impl Error for LengthDelimitedCodecError

impl Error for LengthError

impl Error for LengthLimitError

impl Error for proc_macro::LexError

impl Error for proc_macro2::LexError

impl Error for LibsensorsError

impl Error for LinesCodecError

impl Error for LocationOutOfBoundsError

impl Error for LunisolarDateError

impl Error for MacError

Available on crate feature std only.

impl Error for MailEntryError

impl Error for MailParseError

impl Error for MaildirError

impl Error for MatchError

Available on crate feature std only.

impl Error for MatchError

Available on crate feature std only.

impl Error for MatchesError

impl Error for MaxSizeReached

impl Error for MaybePayloadError

impl Error for MismatchedCalendarError

impl Error for MismatchedCalendarError

impl Error for NamespaceError

impl Error for None

impl Error for NormalizeError

impl Error for NulError

impl Error for OtherError

Available on crate feature std only.

impl Error for OutOfRange

Available on crate feature std only.

impl Error for OutOfRangeError

Available on crate features core-error or std only.

impl Error for PAErr

impl Error for PEMError

impl Error for Parse

impl Error for ParseAlphabetError

Available on crate features std only.

impl Error for ParseBigIntError

Available on crate feature std only.

impl Error for ParseBoolError

impl Error for ParseCharError

impl Error for ParseCharRefError

impl Error for chrono::format::ParseError

Available on crate features core-error or std only.

impl Error for ParseError

Available on crate feature std only.

impl Error for ParseError

impl Error for ParseError

impl Error for ParseError

impl Error for ParseError

Available on crate feature std only.

impl Error for ParseError

impl Error for url::parser::ParseError

Available on crate feature std only.

impl Error for ParseError

impl Error for ParseError

Available on crate feature std only.

impl Error for ParseFloatError

impl Error for ParseFromDescription

impl Error for core::num::error::ParseIntError

impl Error for ParseIntError

impl Error for log::ParseLevelError

Available on crate feature std only.

impl Error for ParseLevelError

Available on crate feature std only.

impl Error for ParseLevelFilterError

Available on crate feature std only.

impl Error for ParseMonthError

Available on crate feature std only.

impl Error for ParseOidError

Available on crate feature std only.

impl Error for ParseValueError

impl Error for ParseWeekdayError

Available on crate feature std only.

impl Error for PatternError

impl Error for PatternError

impl Error for glob::PatternError

impl Error for PatternIDError

Available on crate feature std only.

impl Error for PatternIDError

Available on crate feature std only.

impl Error for PatternLoadError

impl Error for PatternSetInsertError

Available on crate feature std only.

impl Error for PeekHeaderError

impl Error for PemError

Available on crate features std only.

impl Error for PopError

Available on crate feature std only.

impl Error for PreferencesParseError

impl Error for PrefixLenError

impl Error for QuotedPrintableError

Available on crate feature std only.

impl Error for RRuleError

impl Error for RangeError

impl Error for RateLimited

impl Error for ReadError

impl Error for RecurrenceError

impl Error for std::sync::mpsc::RecvError

impl Error for RecvError

impl Error for RecvError

impl Error for RecvError

impl Error for RecvError

impl Error for RecvError

Available on crate feature std only.

impl Error for RecvMessageError

impl Error for std::sync::mpsc::RecvTimeoutError

impl Error for ReplyError

impl Error for ReplyOrIdError

impl Error for ReuniteError

impl Error for ReuniteError

impl Error for RoundingError

Available on crate feature std only.

impl Error for SeError

impl Error for SendError

impl Error for SerError

impl Error for SerializeError

Available on crate feature std only.

impl Error for SerializeError

impl Error for SetGlobalDefaultError

Available on crate feature std only.

impl Error for SetLoggerError

Available on crate feature std only.

impl Error for SmallIndexError

Available on crate feature std only.

impl Error for SpawnError

Available on crate feature std only.

impl Error for SpecificationError

Available on crate feature std only.

impl Error for StartError

Available on crate feature std only.

impl Error for StateIDError

Available on crate feature std only.

impl Error for StateIDError

Available on crate feature std only.

impl Error for Status

impl Error for StripPrefixError

impl Error for SymbolError

impl Error for SyntaxError

impl Error for SystemTimeError

impl Error for ToStrError

impl Error for TomlError

impl Error for TryAcquireError

impl Error for TryCurrentError

impl Error for TryFromCharError

impl Error for TryFromFloatSecsError

impl Error for core::num::error::TryFromIntError

impl Error for TryFromIntError

impl Error for TryFromParsed

impl Error for TryFromSliceError

impl Error for TryGetError

Available on crate feature std only.

impl Error for std::fs::TryLockError

impl Error for TryLockError

impl Error for std::sync::mpsc::TryRecvError

impl Error for TryRecvError

impl Error for TryRecvError

impl Error for TryRecvError

impl Error for TryRecvError

impl Error for TryRecvError

impl Error for TryRecvError

Available on crate feature std only.

impl Error for alloc::collections::TryReserveError

impl Error for TryReserveError

Available on crate feature std only.

impl Error for UleError

impl Error for UnicodeWordBoundaryError

Available on crate feature std only.

impl Error for UnicodeWordError

Available on crate feature std only.

impl Error for UnorderedKeyError

impl Error for UnsupportedCalendarError

impl Error for UnsupportedOperationError

Available on crate feature std only.

impl Error for Utf8Error

impl Error for ValidationError

impl Error for VarError

impl Error for VerifierBuilderError

Available on crate feature std only.

impl Error for WeightedError

Available on crate feature std only.

impl Error for WrappedError

impl Error for WriterPanicked

impl Error for X509Error

impl Error for X509VerifyError

impl Error for ZeroTrieBuildError

impl<'a, T> Error for &'a T

where T: Error + ?Sized,

impl<E> Error for Box<E>

where E: Error,

impl<E> Error for Err<E>

where E: Debug,

Available on crate feature std only.

impl<E> Error for Err<E>

where E: Debug,

Available on crate feature std only.

impl<E> Error for serde_path_to_error::Error<E>

where E: Error,

impl<E> Error for LookupError<E>

where E: Error + 'static,

impl<E> Error for ParserError<E>

where E: Debug,

impl<F> Error for Error<F>

where F: ErrorFormatter,

impl<I, C> Error for TreeError<I, C>

where I: Stream + Clone + Debug + Display + Sync + Send + 'static, C: Display + Debug,

Available on crate feature std only.

impl<I> Error for Error<I>

where I: Debug + Display,

Available on crate feature std only.

impl<I> Error for Error<I>

where I: Debug + Display,

Available on crate feature std only.

impl<I> Error for ExactlyOneError<I>

where I: Iterator + Debug, <I as Iterator>::Item: Debug,

Available on crate feature use_std only.

impl<I> Error for InputError<I>

where I: Clone + Debug + Display + Sync + Send + 'static,

Available on crate feature std only.

impl<I> Error for VerboseError<I>

where I: Debug + Display,

impl<I> Error for VerboseError<I>

where I: Debug + Display,

Available on crate feature std only.

impl<L, R> Error for Either<L, R>

where L: Error, R: Error,

Available on crate features use_std only.

Either implements Error if both L and R implement it.

Requires crate feature "use_std"

impl<RE, T> Error for RequestTokenError<RE, T>

where RE: Error + 'static, T: ErrorResponse + 'static, RequestTokenError<RE, T>: Debug + Display,

impl<RE> Error for HttpClientError<RE>

where RE: Error + 'static, Box<RE>: Error + 'static, HttpClientError<RE>: Debug + Display,

impl<S> Error for HandshakeError<S>

where S: Debug,

impl<S> Error for HandshakeError<S>

where S: Debug,

impl<T, E> Error for TryChunksError<T, E>

where E: Debug + Display,

Available on crate feature std only.

impl<T, E> Error for TryReadyChunksError<T, E>

where E: Debug + Display,

Available on crate feature std only.

impl<T, Item> Error for ReuniteError<T, Item>

where T: Any,

Available on crate feature std only.

impl<T, P> Error for NlError<T, P>

where T: Debug, P: Debug,

impl<T, P> Error for Nlmsgerr<T, P>

where T: Debug, P: Debug,

impl<T> Error for Arc<T>

where T: Error + ?Sized,

impl<T> Error for AsyncFdTryNewError<T>

impl<T> Error for CreationError<T>

where T: Debug,

Available on crate feature std only.

impl<T> Error for CreationError<T>

where T: Debug,

Available on crate feature std only.

impl<T> Error for ForcePushError<T>

where T: Debug,

Available on crate feature std only.

impl<T> Error for PoisonError<T>

impl<T> Error for PollSendError<T>

where T: Debug,

impl<T> Error for PushError<T>

where T: Debug,

Available on crate feature std only.

impl<T> Error for std::sync::oneshot::RecvTimeoutError<T>

impl<T> Error for ReuniteError<T>

where T: Any,

Available on crate feature std only.

impl<T> Error for std::sync::mpsc::SendError<T>

impl<T> Error for SendError<T>

impl<T> Error for SendError<T>

impl<T> Error for SendError<T>

impl<T> Error for SendError<T>

Available on crate feature std only.

impl<T> Error for SendError<T>

where T: Debug,

impl<T> Error for std::sync::mpmc::error::SendTimeoutError<T>

impl<T> Error for SendTimeoutError<T>

Available on crate feature time only.

impl<T> Error for SetError<T>

where T: Debug,

impl<T> Error for SetOnceError<T>

where T: Debug,

impl<T> Error for ThinBox<T>

where T: Error + ?Sized,

impl<T> Error for TryFromBigIntError<T>

where T: Debug,

Available on crate feature std only.

impl<T> Error for std::sync::poison::TryLockError<T>

impl<T> Error for std::sync::oneshot::TryRecvError<T>

impl<T> Error for std::sync::mpsc::TrySendError<T>

impl<T> Error for TrySendError<T>

impl<T> Error for TrySendError<T>

impl<T> Error for TrySendError<T>

Available on crate feature std only.

impl<T> Error for TrySendError<T>

where T: Any,

impl<W> Error for IntoInnerError<W>

where W: Send + Debug,