Struct tokio::sync::MappedMutexGuard

#[must_use = "if unused the Mutex will immediately unlock"]
pub struct MappedMutexGuard<'a, T: ?Sized> { /* fields omitted */ }

A handle to a held Mutex that has had a function applied to it via MutexGuard::map.

This can be used to hold a subfield of the protected data.

Implementations

impl<'a, T: ?Sized> MappedMutexGuard<'a, T>

pub fn map<U, F>(this: Self, f: F) -> MappedMutexGuard<'a, U> where
    F: FnOnce(&mut T) -> &mut U, 

Makes a new MappedMutexGuard for a component of the locked data.

This operation cannot fail as the MappedMutexGuard passed in already locked the mutex.

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

pub fn try_map<U, F>(this: Self, f: F) -> Result<MappedMutexGuard<'a, U>, Self> where
    F: FnOnce(&mut T) -> Option<&mut U>, 

Attempts to make a new MappedMutexGuard for a component of the locked data. The original guard is returned if the closure returns None.

This operation cannot fail as the MappedMutexGuard passed in already locked the mutex.

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

Trait Implementations

impl<'a, T: ?Sized + Debug> Debug for MappedMutexGuard<'a, T>

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

Formats the value using the given formatter.

impl<'a, T: ?Sized> Deref for MappedMutexGuard<'a, T>

type Target = T

The resulting type after dereferencing.

fn deref(&self) -> &Self::Target

Dereferences the value.

impl<'a, T: ?Sized> DerefMut for MappedMutexGuard<'a, T>

fn deref_mut(&mut self) -> &mut Self::Target

Mutably dereferences the value.

impl<'a, T: ?Sized + Display> Display for MappedMutexGuard<'a, T>

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

Formats the value using the given formatter.

impl<'a, T: ?Sized> Drop for MappedMutexGuard<'a, T>

fn drop(&mut self)

Executes the destructor for this type.

impl<'a, T: ?Sized> Send for MappedMutexGuard<'a, T> where
    T: Send + 'a, 

impl<'a, T: ?Sized> Sync for MappedMutexGuard<'a, T> where
    T: Sync + 'a,