pub struct OnceBool { /* private fields */ }
Expand description
A thread-safe cell which can be written to only once.
Implementations§
source§impl 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
pub fn get_or_init<F>(&self, f: F) -> 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>
pub fn get_or_try_init<F, E>(&self, f: F) -> 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§
source§impl<T> BorrowMut<T> for Twhere
T: ?Sized,
impl<T> BorrowMut<T> for Twhere
T: ?Sized,
source§fn borrow_mut(&mut self) -> &mut T
fn borrow_mut(&mut self) -> &mut T
Mutably borrows from an owned value. Read more