pub struct MappedRwLockReadGuard<'a, T>
where T: 'a + ?Sized,
{ data: NonNull<T>, inner_lock: &'a RwLock, }
🔬This is a nightly-only experimental API. (mapped_lock_guards #117108)
Expand description

RAII structure used to release the shared read access of a lock when dropped, which can point to a subfield of the protected data.

This structure is created by the map and try_map methods on RwLockReadGuard.

Fields§

§data: NonNull<T>
🔬This is a nightly-only experimental API. (mapped_lock_guards #117108)
§inner_lock: &'a RwLock
🔬This is a nightly-only experimental API. (mapped_lock_guards #117108)

Implementations§

source§

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

source

pub fn map<U, F>( orig: MappedRwLockReadGuard<'a, T>, f: F ) -> MappedRwLockReadGuard<'a, U>
where F: FnOnce(&T) -> &U, U: ?Sized,

🔬This is a nightly-only experimental API. (mapped_lock_guards #117108)

Makes a MappedRwLockReadGuard for a component of the borrowed data, e.g. an enum variant.

The RwLock is already locked for reading, so this cannot fail.

This is an associated function that needs to be used as MappedRwLockReadGuard::map(...). A method would interfere with methods of the same name on the contents of the MappedRwLockReadGuard used through Deref.

§Panics

If the closure panics, the guard will be dropped (unlocked) and the RwLock will not be poisoned.

source

pub fn try_map<U, F>( orig: MappedRwLockReadGuard<'a, T>, f: F ) -> Result<MappedRwLockReadGuard<'a, U>, MappedRwLockReadGuard<'a, T>>
where F: FnOnce(&T) -> Option<&U>, U: ?Sized,

🔬This is a nightly-only experimental API. (mapped_lock_guards #117108)

Makes a MappedRwLockReadGuard for a component of the borrowed data. The original guard is returned as an Err(...) if the closure returns None.

The RwLock is already locked for reading, so this cannot fail.

This is an associated function that needs to be used as MappedRwLockReadGuard::try_map(...). A method would interfere with methods of the same name on the contents of the MappedRwLockReadGuard used through Deref.

§Panics

If the closure panics, the guard will be dropped (unlocked) and the RwLock will not be poisoned.

Trait Implementations§

source§

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

source§

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

Formats the value using the given formatter. Read more
source§

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

§

type Target = T

The resulting type after dereferencing.
source§

fn deref(&self) -> &T

Dereferences the value.
source§

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

source§

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

Formats the value using the given formatter. Read more
source§

impl<T> Drop for MappedRwLockReadGuard<'_, T>
where T: ?Sized,

source§

fn drop(&mut self)

Executes the destructor for this type. Read more
source§

impl<T> !Send for MappedRwLockReadGuard<'_, T>
where T: ?Sized,

source§

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

Auto Trait Implementations§

§

impl<'a, T: ?Sized> Freeze for MappedRwLockReadGuard<'a, T>

§

impl<'a, T: ?Sized> RefUnwindSafe for MappedRwLockReadGuard<'a, T>
where T: RefUnwindSafe,

§

impl<'a, T: ?Sized> Unpin for MappedRwLockReadGuard<'a, T>

§

impl<'a, T: ?Sized> UnwindSafe for MappedRwLockReadGuard<'a, T>
where T: RefUnwindSafe,

Blanket Implementations§

source§

impl<T> Any for T
where T: 'static + ?Sized,

source§

fn type_id(&self) -> TypeId

Gets the TypeId of self. Read more
source§

impl<T> Borrow<T> for T
where T: ?Sized,

source§

fn borrow(&self) -> &T

Immutably borrows from an owned value. Read more
source§

impl<T> BorrowMut<T> for T
where T: ?Sized,

source§

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

Mutably borrows from an owned value. Read more
source§

impl<T> From<T> for T

source§

fn from(t: T) -> T

Returns the argument unchanged.

source§

impl<T> Instrument for T

source§

fn instrument(self, span: Span) -> Instrumented<Self>

Instruments this type with the provided Span, returning an Instrumented wrapper. Read more
source§

fn in_current_span(self) -> Instrumented<Self>

Instruments this type with the current Span, returning an Instrumented wrapper. Read more
source§

impl<T, U> Into<U> for T
where U: From<T>,

source§

fn into(self) -> U

Calls U::from(self).

That is, this conversion is whatever the implementation of From<T> for U chooses to do.

source§

impl<T> ToString for T
where T: Display + ?Sized,

source§

default fn to_string(&self) -> String

Converts the given value to a String. Read more
source§

impl<T, U> TryFrom<U> for T
where U: Into<T>,

§

type Error = Infallible

The type returned in the event of a conversion error.
source§

fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>

Performs the conversion.
source§

impl<T, U> TryInto<U> for T
where U: TryFrom<T>,

§

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

The type returned in the event of a conversion error.
source§

fn try_into(self) -> Result<U, <U as TryFrom<T>>::Error>

Performs the conversion.
source§

impl<T> WithSubscriber for T

source§

fn with_subscriber<S>(self, subscriber: S) -> WithDispatch<Self>
where S: Into<Dispatch>,

Attaches the provided Subscriber to this type, returning a WithDispatch wrapper. Read more
source§

fn with_current_subscriber(self) -> WithDispatch<Self>

Attaches the current default Subscriber to this type, returning a WithDispatch wrapper. Read more