# Trait bitflags::__core::error::Error [−] [src]

    pub trait Error: Reflect + Debug + Display {
        fn description(&self) -> &str;

        fn cause(&self) -> Option<&Error> { ... }
    }

Base functionality for all errors in Rust.

## Required Methods

### `fn description(&self) -> &str`

A short description of the error.

The description should not contain newlines or sentence-ending punctuation, to facilitate embedding in larger user-facing strings.

## Provided Methods

### `fn cause(&self) -> Option<&Error>`

The lower-level cause of this error, if any.

## Methods

### `impl Error + 'static`

#### `fn is<T>(&self) -> bool where T: 'static + Error` 1.3.0

Returns true if the boxed type is the same as `T`

#### `fn downcast_ref<T>(&self) -> Option<&T> where T: 'static + Error` 1.3.0

Returns some reference to the boxed value if it is of type `T`, or `None` if it isn't.

#### `fn downcast_mut<T>(&mut self) -> Option<&mut T> where T: 'static + Error` 1.3.0

Returns some mutable reference to the boxed value if it is of type `T`, or `None` if it isn't.

### `impl Error + 'static + Send`

#### `fn is<T>(&self) -> bool where T: 'static + Error` 1.3.0

Forwards to the method defined on the type `Any`.

#### `fn downcast_ref<T>(&self) -> Option<&T> where T: 'static + Error` 1.3.0

Forwards to the method defined on the type `Any`.

#### `fn downcast_mut<T>(&mut self) -> Option<&mut T> where T: 'static + Error` 1.3.0

Forwards to the method defined on the type `Any`.

### `impl Error + 'static + Send + Sync`

#### `fn is<T>(&self) -> bool where T: 'static + Error` 1.3.0

Forwards to the method defined on the type `Any`.

#### `fn downcast_ref<T>(&self) -> Option<&T> where T: 'static + Error` 1.3.0

Forwards to the method defined on the type `Any`.

#### `fn downcast_mut<T>(&mut self) -> Option<&mut T> where T: 'static + Error` 1.3.0

Forwards to the method defined on the type `Any`.

### `impl Error + 'static`

#### `fn downcast<T>(self: Box<Error + 'static>) -> Result<Box<T>, Box<Error + 'static>> where T: 'static + Error` 1.3.0

Attempt to downcast the box to a concrete type.

### `impl Error + 'static + Send`

#### `fn downcast<T>(self: Box<Error + 'static + Send>) -> Result<Box<T>, Box<Error + 'static + Send>> where T: 'static + Error` 1.3.0

Attempt to downcast the box to a concrete type.

### `impl Error + 'static + Send + Sync`

#### `fn downcast<T>(self: Box<Error + 'static + Send + Sync>) -> Result<Box<T>, Box<Error + 'static + Send + Sync>> where T: 'static + Error` 1.3.0

Attempt to downcast the box to a concrete type.

## Implementors

- `impl Error for ParseBoolError`
- `impl Error for Utf8Error`
- `impl Error for ParseIntError`
- `impl Error for ParseFloatError`
- `impl Error for FromUtf8Error`
- `impl Error for FromUtf16Error`
- `impl Error for ParseError`
- `impl Error for DecodeUtf16Error`
- `impl<T> Error for Box<T> where T: Error`
- `impl Error for VarError`
- `impl Error for JoinPathsError`
- `impl Error for NulError`
- `impl Error for IntoStringError`
- `impl<W> Error for IntoInnerError<W> where W: Send + Reflect + Debug`
- `impl Error for Error`
- `impl Error for CharsError`
- `impl Error for AddrParseError`
- `impl Error for StripPrefixError`
- `impl<T> Error for SendError<T> where T: Send + Reflect`
- `impl<T> Error for TrySendError<T> where T: Send + Reflect`
- `impl Error for RecvError`
- `impl Error for TryRecvError`
- `impl Error for SystemTimeError`
- `impl<T> Error for PoisonError<T> where T: Reflect`
- `impl<T> Error for TryLockError<T> where T: Reflect`

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