# 1.0.0[−][src]Struct std::sync::PoisonError

    pub struct PoisonError<T> { /* fields omitted */ }

A type of error which can be returned whenever a lock is acquired.

Both `Mutex`es and `RwLock`s are poisoned whenever a thread fails while the lock is held. The precise semantics for when a lock is poisoned is documented on each lock, but once a lock is poisoned then all future acquisitions will return this error.

# Examples

    use std::sync::{Arc, Mutex};
    use std::thread;

    let mutex = Arc::new(Mutex::new(1));

    // poison the mutex
    let c_mutex = mutex.clone();
    let _ = thread::spawn(move || {
        let mut data = c_mutex.lock().unwrap();
        *data = 2;
        panic!();
    }).join();

    match mutex.lock() {
        Ok(_) => unreachable!(),
        Err(p_err) => {
            let data = p_err.get_ref();
            println!("recovered: {}", data);
        }
    };

Run

## Implementations

### `impl<T> PoisonError<T>`[src]

#### `pub fn new(guard: T) -> PoisonError<T>`1.2.0[src]

Creates a `PoisonError`.

This is generally created by methods like `Mutex::lock` or `RwLock::read`.

#### `pub fn into_inner(self) -> T` 1.2.0[src]

Consumes this error indicating that a lock is poisoned, returning the underlying guard to allow access regardless.

# Examples

    use std::collections::HashSet;
    use std::sync::{Arc, Mutex};
    use std::thread;

    let mutex = Arc::new(Mutex::new(HashSet::new()));

    // poison the mutex
    let c_mutex = mutex.clone();
    let _ = thread::spawn(move || {
        let mut data = c_mutex.lock().unwrap();
        data.insert(10);
        panic!();
    }).join();

    let p_err = mutex.lock().unwrap_err();
    let data = p_err.into_inner();
    println!("recovered {} items", data.len());

Run

#### `pub fn get_ref(&self) -> &T` 1.2.0[src]

Reaches into this error indicating that a lock is poisoned, returning a reference to the underlying guard to allow access regardless.

#### `pub fn get_mut(&mut self) -> &mut T` 1.2.0[src]

Reaches into this error indicating that a lock is poisoned, returning a mutable reference to the underlying guard to allow access regardless.

## Trait Implementations

### `impl<T> Debug for PoisonError<T>`[src]

#### `fn fmt(&self, f: &mut Formatter) -> Result`[src]

Formats the value using the given formatter. Read more

### `impl<T> Display for PoisonError<T>`[src]

#### `fn fmt(&self, f: &mut Formatter) -> Result`[src]

Formats the value using the given formatter. Read more

### `impl<T> Error for PoisonError<T>`[src]

#### `fn description(&self) -> &str`[src]

👎 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); }` Read more

#### `fn source(&self) -> Option<&(dyn Error + 'static)>`1.30.0[src]

The lower-level source of this error, if any. Read more

#### `fn backtrace(&self) -> Option<&Backtrace>`[src]

🔬 This is a nightly-only experimental API. (`backtrace` #53487)

Returns a stack backtrace, if available, of where this error occurred. Read more

#### `fn cause(&self) -> Option<&dyn Error>`[src]

👎 Deprecated since 1.33.0:

replaced by Error::source, which can support downcasting

### `impl<T> From<PoisonError<T>> for TryLockError<T>`[src]

#### `fn from(err: PoisonError<T>) -> TryLockError<T>`[src]

Performs the conversion.

## Auto Trait Implementations

### `impl<T> RefUnwindSafe for PoisonError<T> where
T: RefUnwindSafe,`

### `impl<T> Send for PoisonError<T> where
T: Send,`

### `impl<T> Sync for PoisonError<T> where
T: Sync,`

### `impl<T> Unpin for PoisonError<T> where
T: Unpin,`

### `impl<T> UnwindSafe for PoisonError<T> where
T: UnwindSafe,`

## Blanket Implementations

### `impl<T> Any for T where
T: 'static + ?Sized,` [src]

#### `fn type_id(&self) -> TypeId`[src]

Gets the `TypeId` of `self`. Read more

### `impl<T> Borrow<T> for T where
T: ?Sized,` [src]

#### `fn borrow(&self) -> &T`[src]

Immutably borrows from an owned value. Read more

### `impl<T> BorrowMut<T> for T where
T: ?Sized,` [src]

#### `fn borrow_mut(&mut self) -> &mut T`[src]

Mutably borrows from an owned value. Read more

### `impl<T> From<T> for T`[src]

#### `fn from(t: T) -> T`[src]

Performs the conversion.

### `impl<T, U> Into<U> for T where
U: From<T>,` [src]

#### `fn into(self) -> U`[src]

Performs the conversion.

### `impl<T> ToString for T where
T: Display + ?Sized,` [src]

#### `default fn to_string(&self) -> String`[src]

Converts the given value to a `String`. Read more

### `impl<T, U> TryFrom<U> for T where
U: Into<T>,` [src]

#### `type Error = Infallible`

The type returned in the event of a conversion error.

#### `fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>`[src]

Performs the conversion.

### `impl<T, U> TryInto<U> for T where
U: TryFrom<T>,` [src]

#### `type Error = <U as TryFrom<T>>::Error`

The type returned in the event of a conversion error.

#### `fn try_into(self) -> Result<U, <U as TryFrom<T>>::Error>`[src]

Performs the conversion.