# Trait std::error::Error [−] [src]

    pub trait Error: Debug + Display + Reflect {
        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: Error + 'static>(&self) -> bool`

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

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

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

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

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: Error + 'static>(&self) -> bool`

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

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

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

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

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

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

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

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

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

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

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

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

### `impl Error`

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

Attempt to downcast the box to a concrete type.

### `impl Error + Send`

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

Attempt to downcast the box to a concrete type.

### `impl Error + Send + Sync`

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

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 VarError`
- `impl Error for JoinPathsError`
- `impl Error for NulError`
- `impl Error for IntoStringError`
- `impl<W: Reflect + Send + Debug> Error for IntoInnerError<W>`
- `impl Error for Error`
- `impl Error for CharsError`
- `impl Error for AddrParseError`
- `impl Error for StripPrefixError`
- `impl<T: Send + Reflect> Error for SendError<T>`
- `impl<T: Send + Reflect> Error for TrySendError<T>`
- `impl Error for RecvError`
- `impl Error for TryRecvError`
- `impl Error for SystemTimeError`
- `impl<T: Send + Reflect> Error for PoisonError<T>`
- `impl<T: Send + Reflect> Error for TryLockError<T>`

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