Struct smol::lock::RwLockWriteGuard

pub struct RwLockWriteGuard<'a, T> where
    T: ?Sized,  { /* fields omitted */ }

A guard that releases the write lock when dropped.

Implementations

impl<'a, T> RwLockWriteGuard<'a, T> where
    T: ?Sized, 

pub fn downgrade(guard: RwLockWriteGuard<'a, T>) -> RwLockReadGuard<'a, T>

Downgrades into a regular reader guard.

Examples

use async_lock::{RwLock, RwLockWriteGuard};

let lock = RwLock::new(1);

let mut writer = lock.write().await;
*writer += 1;

assert!(lock.try_read().is_none());

let reader = RwLockWriteGuard::downgrade(writer);
assert_eq!(*reader, 2);

assert!(lock.try_read().is_some());

pub fn downgrade_to_upgradable(
    guard: RwLockWriteGuard<'a, T>
) -> RwLockUpgradableReadGuard<'a, T>

Downgrades into an upgradable reader guard.

Examples

use async_lock::{RwLock, RwLockUpgradableReadGuard, RwLockWriteGuard};

let lock = RwLock::new(1);

let mut writer = lock.write().await;
*writer += 1;

assert!(lock.try_read().is_none());

let reader = RwLockWriteGuard::downgrade_to_upgradable(writer);
assert_eq!(*reader, 2);

assert!(lock.try_write().is_none());
assert!(lock.try_read().is_some());

assert!(RwLockUpgradableReadGuard::try_upgrade(reader).is_ok())

Trait Implementations

impl<'_, T> Debug for RwLockWriteGuard<'_, T> where
    T: Debug + ?Sized, 

fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter.

impl<'_, T> Deref for RwLockWriteGuard<'_, T> where
    T: ?Sized, 

type Target = T

The resulting type after dereferencing.

fn deref(&self) -> &T

Dereferences the value.

impl<'_, T> DerefMut for RwLockWriteGuard<'_, T> where
    T: ?Sized, 

fn deref_mut(&mut self) -> &mut T

Mutably dereferences the value.

impl<'_, T> Display for RwLockWriteGuard<'_, T> where
    T: Display + ?Sized, 

fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter.

impl<'_, T> Send for RwLockWriteGuard<'_, T> where
    T: Send + ?Sized, 

impl<'_, T> Sync for RwLockWriteGuard<'_, T> where
    T: Sync + ?Sized,