pub struct Value<'a, T> { /* private fields */ }
Expand description
Abstraction over some optional value T
that is stored in the dispatch context.
Implementations§
Source§impl<T> Value<'_, T>
impl<T> Value<'_, T>
Sourcepub fn set(&mut self, new_value: T)
pub fn set(&mut self, new_value: T)
Set to the given value.
Self::get
and Self::get_mut
will return new_value
afterwards.
Sourcepub fn or_default(&mut self) -> &mut Twhere
T: Default,
pub fn or_default(&mut self) -> &mut Twhere
T: Default,
Returns a mutable reference to the value.
If the internal value isn’t initialized, this will set it to Default::default()
before
returning the mutable reference.
Sourcepub fn clear(&mut self)
pub fn clear(&mut self)
Clear the internal value.
Self::get
and Self::get_mut
will return None
afterwards.
Auto Trait Implementations§
impl<'a, T> Freeze for Value<'a, T>where
T: Freeze,
impl<'a, T> RefUnwindSafe for Value<'a, T>where
T: RefUnwindSafe,
impl<'a, T> Send for Value<'a, T>where
T: Send,
impl<'a, T> Sync for Value<'a, T>where
T: Sync,
impl<'a, T> Unpin for Value<'a, T>where
T: Unpin,
impl<'a, T> !UnwindSafe for Value<'a, T>
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
Source§impl<T> CheckedConversion for T
impl<T> CheckedConversion for T
Source§impl<T> Instrument for T
impl<T> Instrument for T
Source§fn instrument(self, span: Span) -> Instrumented<Self>
fn instrument(self, span: Span) -> Instrumented<Self>
Source§fn in_current_span(self) -> Instrumented<Self>
fn in_current_span(self) -> Instrumented<Self>
Source§impl<T> IntoEither for T
impl<T> IntoEither for T
Source§fn into_either(self, into_left: bool) -> Either<Self, Self> ⓘ
fn into_either(self, into_left: bool) -> Either<Self, Self> ⓘ
Converts
self
into a Left
variant of Either<Self, Self>
if into_left
is true
.
Converts self
into a Right
variant of Either<Self, Self>
otherwise. Read moreSource§fn into_either_with<F>(self, into_left: F) -> Either<Self, Self> ⓘ
fn into_either_with<F>(self, into_left: F) -> Either<Self, Self> ⓘ
Converts
self
into a Left
variant of Either<Self, Self>
if into_left(&self)
returns true
.
Converts self
into a Right
variant of Either<Self, Self>
otherwise. Read moreSource§impl<Src, Dest> IntoTuple<Dest> for Srcwhere
Dest: FromTuple<Src>,
impl<Src, Dest> IntoTuple<Dest> for Srcwhere
Dest: FromTuple<Src>,
fn into_tuple(self) -> Dest
Source§impl<T, Outer> IsWrappedBy<Outer> for T
impl<T, Outer> IsWrappedBy<Outer> for T
Source§impl<T> SaturatedConversion for T
impl<T> SaturatedConversion for T
Source§fn saturated_from<T>(t: T) -> Selfwhere
Self: UniqueSaturatedFrom<T>,
fn saturated_from<T>(t: T) -> Selfwhere
Self: UniqueSaturatedFrom<T>,
Source§fn saturated_into<T>(self) -> Twhere
Self: UniqueSaturatedInto<T>,
fn saturated_into<T>(self) -> Twhere
Self: UniqueSaturatedInto<T>,
Consume self to return an equivalent value of
T
. Read moreSource§impl<T, U> TryIntoKey<U> for Twhere
U: TryFromKey<T>,
impl<T, U> TryIntoKey<U> for Twhere
U: TryFromKey<T>,
type Error = <U as TryFromKey<T>>::Error
fn try_into_key(self) -> Result<U, <U as TryFromKey<T>>::Error>
Source§impl<S, T> UncheckedInto<T> for Swhere
T: UncheckedFrom<S>,
impl<S, T> UncheckedInto<T> for Swhere
T: UncheckedFrom<S>,
Source§fn unchecked_into(self) -> T
fn unchecked_into(self) -> T
The counterpart to
unchecked_from
.Source§impl<T, S> UniqueSaturatedInto<T> for S
impl<T, S> UniqueSaturatedInto<T> for S
Source§fn unique_saturated_into(self) -> T
fn unique_saturated_into(self) -> T
Consume self to return an equivalent value of
T
.