Struct futures::lock::MutexGuard  
source · pub struct MutexGuard<'a, T>where
    T: ?Sized,{ /* private fields */ }Expand description
An RAII guard returned by the lock and try_lock methods.
When this structure is dropped (falls out of scope), the lock will be
unlocked.
Implementations§
source§impl<'a, T> MutexGuard<'a, T>where
    T: ?Sized,
 
impl<'a, T> MutexGuard<'a, T>where
    T: ?Sized,
sourcepub fn map<U, F>(this: MutexGuard<'a, T>, f: F) -> MappedMutexGuard<'a, T, U>where
    F: FnOnce(&mut T) -> &mut U,
    U: ?Sized,
 
pub fn map<U, F>(this: MutexGuard<'a, T>, f: F) -> MappedMutexGuard<'a, T, U>where
    F: FnOnce(&mut T) -> &mut U,
    U: ?Sized,
Returns a locked view over a portion of the locked data.
Example
use futures::lock::{Mutex, MutexGuard};
let data = Mutex::new(Some("value".to_string()));
{
    let locked_str = MutexGuard::map(data.lock().await, |opt| opt.as_mut().unwrap());
    assert_eq!(&*locked_str, "value");
}