Struct tokio::sync::OwnedRwLockReadGuard [−][src]
sync
only.Expand description
Owned RAII structure used to release the shared read access of a lock when dropped.
This structure is created by the read_owned
method on
RwLock
.
Implementations
Make a new OwnedRwLockReadGuard
for a component of the locked data.
This operation cannot fail as the OwnedRwLockReadGuard
passed in
already locked the data.
This is an associated function that needs to be
used as OwnedRwLockReadGuard::map(...)
. A method would interfere with
methods of the same name on the contents of the locked data.
Examples
use std::sync::Arc; use tokio::sync::{RwLock, OwnedRwLockReadGuard}; #[derive(Debug, Clone, Copy, PartialEq, Eq)] struct Foo(u32); let lock = Arc::new(RwLock::new(Foo(1))); let guard = lock.read_owned().await; let guard = OwnedRwLockReadGuard::map(guard, |f| &f.0); assert_eq!(1, *guard);
Attempts to make a new OwnedRwLockReadGuard
for a component of the
locked data. The original guard is returned if the closure returns
None
.
This operation cannot fail as the OwnedRwLockReadGuard
passed in
already locked the data.
This is an associated function that needs to be used as
OwnedRwLockReadGuard::try_map(..)
. A method would interfere with
methods of the same name on the contents of the locked data.
Examples
use std::sync::Arc; use tokio::sync::{RwLock, OwnedRwLockReadGuard}; #[derive(Debug, Clone, Copy, PartialEq, Eq)] struct Foo(u32); let lock = Arc::new(RwLock::new(Foo(1))); let guard = lock.read_owned().await; let guard = OwnedRwLockReadGuard::try_map(guard, |f| Some(&f.0)).expect("should not fail"); assert_eq!(1, *guard);
Trait Implementations
Auto Trait Implementations
impl<T, U = T> !RefUnwindSafe for OwnedRwLockReadGuard<T, U>
impl<T: ?Sized, U: ?Sized> Unpin for OwnedRwLockReadGuard<T, U> where
T: Unpin,
impl<T, U = T> !UnwindSafe for OwnedRwLockReadGuard<T, U>