pub struct OnceBool { /* private fields */ }
Expand description
A thread-safe cell which can be written to only once.
Implementations§
§impl OnceBool
impl OnceBool
pub 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.
pub fn get_or_init<F>(&self, f: F) -> boolwhere
F: FnOnce() -> bool,
pub fn get_or_init<F>(&self, f: F) -> boolwhere 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
.
pub 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§
§impl<T, U> AsBindGroupShaderType<U> for Twhere
U: ShaderType,
&'a T: for<'a> Into<U>,
impl<T, U> AsBindGroupShaderType<U> for Twhere U: ShaderType, &'a T: for<'a> Into<U>,
§fn as_bind_group_shader_type(&self, _images: &RenderAssets<Image>) -> U
fn as_bind_group_shader_type(&self, _images: &RenderAssets<Image>) -> U
Return the
T
ShaderType
for self
. When used in AsBindGroup
derives, it is safe to assume that all images in self
exist.§impl<T> Downcast for Twhere
T: Any,
impl<T> Downcast for Twhere T: Any,
§fn into_any(self: Box<T, Global>) -> Box<dyn Any + 'static, Global>
fn into_any(self: Box<T, Global>) -> Box<dyn Any + 'static, Global>
Convert
Box<dyn Trait>
(where Trait: Downcast
) to Box<dyn Any>
. Box<dyn Any>
can
then be further downcast
into Box<ConcreteType>
where ConcreteType
implements Trait
.§fn into_any_rc(self: Rc<T>) -> Rc<dyn Any + 'static>
fn into_any_rc(self: Rc<T>) -> Rc<dyn Any + 'static>
Convert
Rc<Trait>
(where Trait: Downcast
) to Rc<Any>
. Rc<Any>
can then be
further downcast
into Rc<ConcreteType>
where ConcreteType
implements Trait
.§fn as_any(&self) -> &(dyn Any + 'static)
fn as_any(&self) -> &(dyn Any + 'static)
Convert
&Trait
(where Trait: Downcast
) to &Any
. This is needed since Rust cannot
generate &Any
’s vtable from &Trait
’s.§fn as_any_mut(&mut self) -> &mut (dyn Any + 'static)
fn as_any_mut(&mut self) -> &mut (dyn Any + 'static)
Convert
&mut Trait
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) to &Any
. This is needed since Rust cannot
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’s vtable from &mut Trait
’s.§impl<S> FromSample<S> for S
impl<S> FromSample<S> for S
fn from_sample_(s: S) -> S
§impl<T> FromWorld for Twhere
T: Default,
impl<T> FromWorld for Twhere T: Default,
§fn from_world(_world: &mut World) -> T
fn from_world(_world: &mut World) -> T
Creates
Self
using data from the given World