Trait xmz_server::prelude::Error 1.0.0[−][src]
pub trait Error: Debug + Display { fn description(&self) -> &str { ... } fn cause(&self) -> Option<&Error> { ... } }
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, and may provide
cause chain information:
The cause method is generally used when errors cross "abstraction
boundaries", i.e. when a one module must report an error that is "caused"
by an error from a lower-level module. This setup makes it possible for the
high-level module to provide its own errors that do not commit to any
particular implementation, but also reveal some of its implementation for
debugging via cause chains.
Provided Methods
fn description(&self) -> &str
This method is soft-deprecated.
Although using it won’t cause compilation warning,
new code should use Display instead
and new impls can omit it.
To obtain error description as a string, use to_string().
Examples
match "xc".parse::<u32>() { Err(e) => { // Print `e` itself, not `e.description()`. println!("Error: {}", e); } _ => println!("No error"), }
fn cause(&self) -> Option<&Error>
The lower-level cause of this error, if any.
Examples
use std::error::Error; use std::fmt; #[derive(Debug)] struct SuperError { side: 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 description(&self) -> &str { "I'm the superhero of errors" } fn cause(&self) -> Option<&Error> { Some(&self.side) } } #[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 description(&self) -> &str { "I'm SuperError side kick" } } fn get_super_error() -> Result<(), SuperError> { Err(SuperError { side: SuperErrorSideKick }) } fn main() { match get_super_error() { Err(e) => { println!("Error: {}", e.description()); println!("Caused by: {}", e.cause().unwrap()); } _ => println!("No error"), } }
Methods
impl Error + 'static[src]
impl Error + 'staticpub fn is<T>(&self) -> bool where
T: 'static + Error, 1.3.0[src]
pub fn is<T>(&self) -> bool where
T: 'static + Error, Returns true if the boxed type is the same as T
pub fn downcast_ref<T>(&self) -> Option<&T> where
T: 'static + Error, 1.3.0[src]
pub fn downcast_ref<T>(&self) -> Option<&T> where
T: 'static + Error, Returns some reference to the boxed 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: 'static + Error, 1.3.0[src]
pub fn downcast_mut<T>(&mut self) -> Option<&mut T> where
T: 'static + Error, Returns some mutable reference to the boxed value if it is of type T, or
None if it isn't.
impl Error + 'static + Send[src]
impl Error + 'static + Sendpub fn is<T>(&self) -> bool where
T: 'static + Error, 1.3.0[src]
pub fn is<T>(&self) -> bool where
T: 'static + Error, Forwards to the method defined on the type Any.
pub fn downcast_ref<T>(&self) -> Option<&T> where
T: 'static + Error, 1.3.0[src]
pub fn downcast_ref<T>(&self) -> Option<&T> where
T: 'static + Error, Forwards to the method defined on the type Any.
pub fn downcast_mut<T>(&mut self) -> Option<&mut T> where
T: 'static + Error, 1.3.0[src]
pub fn downcast_mut<T>(&mut self) -> Option<&mut T> where
T: 'static + Error, Forwards to the method defined on the type Any.
impl Error + 'static + Sync + Send[src]
impl Error + 'static + Sync + Sendpub fn is<T>(&self) -> bool where
T: 'static + Error, 1.3.0[src]
pub fn is<T>(&self) -> bool where
T: 'static + Error, Forwards to the method defined on the type Any.
pub fn downcast_ref<T>(&self) -> Option<&T> where
T: 'static + Error, 1.3.0[src]
pub fn downcast_ref<T>(&self) -> Option<&T> where
T: 'static + Error, Forwards to the method defined on the type Any.
pub fn downcast_mut<T>(&mut self) -> Option<&mut T> where
T: 'static + Error, 1.3.0[src]
pub fn downcast_mut<T>(&mut self) -> Option<&mut T> where
T: 'static + Error, Forwards to the method defined on the type Any.
impl Error + 'static[src]
impl Error + 'staticpub fn downcast<T>(
self: Box<Error + 'static>
) -> Result<Box<T>, Box<Error + 'static>> where
T: 'static + Error, 1.3.0[src]
pub fn downcast<T>(
self: Box<Error + 'static>
) -> Result<Box<T>, Box<Error + 'static>> where
T: 'static + Error, Attempt to downcast the box to a concrete type.
impl Error + 'static + Send[src]
impl Error + 'static + Sendpub fn downcast<T>(
self: Box<Error + 'static + Send>
) -> Result<Box<T>, Box<Error + 'static + Send>> where
T: 'static + Error, 1.3.0[src]
pub fn downcast<T>(
self: Box<Error + 'static + Send>
) -> Result<Box<T>, Box<Error + 'static + Send>> where
T: 'static + Error, Attempt to downcast the box to a concrete type.
impl Error + 'static + Sync + Send[src]
impl Error + 'static + Sync + Sendpub fn downcast<T>(
self: Box<Error + 'static + Sync + Send>
) -> Result<Box<T>, Box<Error + 'static + Sync + Send>> where
T: 'static + Error, 1.3.0[src]
pub fn downcast<T>(
self: Box<Error + 'static + Sync + Send>
) -> Result<Box<T>, Box<Error + 'static + Sync + Send>> where
T: 'static + Error, Attempt to downcast the box to a concrete type.
Trait Implementations
impl Trait for Error + 'static + Send[src]
impl Trait for Error + 'static + Sendimpl Trait for Error + 'static + Sync[src]
impl Trait for Error + 'static + Syncimpl Trait for Error + 'static + Sync + Send[src]
impl Trait for Error + 'static + Sync + SendImplementations on Foreign Types
impl Error for TryFromSliceError[src]
impl Error for TryFromSliceErrorimpl Error for ParseFloatError[src]
impl Error for ParseFloatErrorimpl Error for JoinPathsError[src]
impl Error for JoinPathsErrorimpl<T> Error for Box<T> where
T: Error, [src]
impl<T> Error for Box<T> where
T: Error, impl<T> Error for TrySendError<T> where
T: Send, [src]
impl<T> Error for TrySendError<T> where
T: Send, impl Error for RecvError[src]
impl Error for RecvErrorimpl Error for CharsError[src]
impl Error for CharsErrorimpl Error for CannotReallocInPlace[src]
impl Error for CannotReallocInPlaceimpl Error for ParseBoolError[src]
impl Error for ParseBoolErrorimpl Error for BorrowMutError[src]
impl Error for BorrowMutErrorimpl<W> Error for IntoInnerError<W> where
W: Send + Debug, [src]
impl<W> Error for IntoInnerError<W> where
W: Send + Debug, impl Error for IntoStringError[src]
impl Error for IntoStringErrorimpl<T> Error for PoisonError<T>[src]
impl<T> Error for PoisonError<T>impl Error for RecvTimeoutError[src]
impl Error for RecvTimeoutErrorimpl Error for ![src]
impl Error for !impl Error for ParseCharError[src]
impl Error for ParseCharErrorimpl Error for FromUtf8Error[src]
impl Error for FromUtf8Errorimpl Error for FromUtf16Error[src]
impl Error for FromUtf16Errorimpl Error for TryRecvError[src]
impl Error for TryRecvErrorimpl Error for LayoutErr[src]
impl Error for LayoutErrimpl Error for CharTryFromError[src]
impl Error for CharTryFromErrorimpl Error for TryFromIntError[src]
impl Error for TryFromIntErrorimpl Error for Error[src]
impl Error for Errorimpl Error for ParseError[src]
impl Error for ParseErrorimpl Error for VarError[src]
impl Error for VarErrorimpl Error for ParseIntError[src]
impl Error for ParseIntErrorimpl<T> Error for TryLockError<T>[src]
impl<T> Error for TryLockError<T>impl Error for AddrParseError[src]
impl Error for AddrParseErrorimpl Error for DecodeUtf16Error[src]
impl Error for DecodeUtf16Errorimpl Error for NulError[src]
impl Error for NulErrorimpl Error for BorrowError[src]
impl Error for BorrowErrorimpl<T> Error for SendError<T> where
T: Send, [src]
impl<T> Error for SendError<T> where
T: Send, impl Error for FromBytesWithNulError[src]
impl Error for FromBytesWithNulErrorimpl Error for Utf8Error[src]
impl Error for Utf8Errorimpl Error for AllocErr[src]
impl Error for AllocErrimpl Error for SystemTimeError[src]
impl Error for SystemTimeErrorimpl Error for StripPrefixError[src]
impl Error for StripPrefixErrorimpl Error for Error[src]
impl Error for Errorimpl Error for Error[src]
impl Error for Errorimpl Error for DatetimeParseError[src]
impl Error for DatetimeParseErrorimpl Error for Error[src]
impl Error for Errorimpl Error for Error[src]
impl Error for Errorimpl Error for SetLoggerError[src]
impl Error for SetLoggerErrorimpl Error for ParseLevelError[src]
impl Error for ParseLevelErrorimpl Error for ErrorKind[src]
impl Error for ErrorKindimpl Error for TimerError[src]
impl Error for TimerErrorimpl Error for LaunchError[src]
impl Error for LaunchErrorimpl Error for ConfigError[src]
impl Error for ConfigErrorimpl Error for SetLoggerError[src]
impl Error for SetLoggerErrorimpl Error for ShutdownLoggerError[src]
impl Error for ShutdownLoggerErrorimpl Error for Error[src]
impl Error for Errorimpl Error for DecodeError[src]
impl Error for DecodeErrorimpl Error for OutOfRangeError[src]
impl Error for OutOfRangeErrorimpl Error for ParseError[src]
impl Error for ParseErrorimpl Error for ParseError[src]
impl Error for ParseErrorimpl Error for Error[src]
impl Error for Errorimpl Error for Error[src]
impl Error for Errorimpl Error for ParseError[src]
impl Error for ParseErrorimpl Error for Unspecified[src]
impl Error for Unspecifiedimpl Error for DecodeError[src]
impl Error for DecodeErrorimpl Error for Error[src]
impl Error for ErrorImplementors
impl Error for ServerErrorimpl Error for MesszelleErrorimpl Error for OutputErrorimpl Error for xmz_server::prelude::fmt::Error