Struct rbatis_core::runtime::sync::RwLockWriteGuard [−]
pub struct RwLockWriteGuard<'a, T> where
T: ?Sized, { /* fields omitted */ }Expand description
A guard that releases the write lock when dropped.
Implementations
impl<'a, T> RwLockWriteGuard<'a, T> where
T: ?Sized,
impl<'a, T> RwLockWriteGuard<'a, T> where
T: ?Sized,
pub fn downgrade(guard: RwLockWriteGuard<'a, T>) -> RwLockReadGuard<'a, T>
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>
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())