pub struct OnceBool { /* private fields */ }
Expand description
A thread-safe cell which can be written to only once.
Implementations
sourceimpl OnceBool
impl OnceBool
sourcepub fn set(&self, value: bool) -> Result<(), ()>
pub fn set(&self, value: bool) -> Result<(), ()>
Sets the contents of this cell to value
.
Returns Ok(())
if the cell was empty and Err(())
if it was
full.
sourcepub fn get_or_init<F>(&self, f: F) -> bool where
F: FnOnce() -> bool,
pub fn get_or_init<F>(&self, f: F) -> bool where
F: FnOnce() -> bool,
Gets the contents of the cell, initializing it with f
if the cell was
empty.
If several threads concurrently run get_or_init
, more than one f
can
be called. However, all threads will return the same value, produced by
some f
.
sourcepub fn get_or_try_init<F, E>(&self, f: F) -> Result<bool, E> where
F: FnOnce() -> Result<bool, E>,
pub fn get_or_try_init<F, E>(&self, f: F) -> Result<bool, E> where
F: FnOnce() -> Result<bool, E>,
Gets the contents of the cell, initializing it with f
if
the cell was empty. If the cell was empty and f
failed, an
error is returned.
If several threads concurrently run get_or_init
, more than one f
can
be called. However, all threads will return the same value, produced by
some f
.
Trait Implementations
Auto Trait Implementations
impl RefUnwindSafe for OnceBool
impl Send for OnceBool
impl Sync for OnceBool
impl Unpin for OnceBool
impl UnwindSafe for OnceBool
Blanket Implementations
sourceimpl<T> BorrowMut<T> for T where
T: ?Sized,
impl<T> BorrowMut<T> for T where
T: ?Sized,
const: unstable · sourcefn borrow_mut(&mut self) -> &mut T
fn borrow_mut(&mut self) -> &mut T
Mutably borrows from an owned value. Read more