pub struct Empty;Expand description
An empty field.
This can be used to indicate that the value of a field is not currently present but will be recorded later.
When a field’s value is Empty. it will not be recorded.
Trait Implementations§
impl Eq for Empty
impl StructuralPartialEq for Empty
Auto Trait Implementations§
impl Freeze for Empty
impl RefUnwindSafe for Empty
impl Send for Empty
impl Sync for Empty
impl Unpin for Empty
impl UnwindSafe for Empty
Blanket Implementations§
Source§impl<T> ArchivePointee for T
impl<T> ArchivePointee for T
Source§type ArchivedMetadata = ()
type ArchivedMetadata = ()
The archived version of the pointer metadata for this type.
Source§fn pointer_metadata(
_: &<T as ArchivePointee>::ArchivedMetadata,
) -> <T as Pointee>::Metadata
fn pointer_metadata( _: &<T as ArchivePointee>::ArchivedMetadata, ) -> <T as Pointee>::Metadata
Converts some archived metadata to the pointer metadata for itself.
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
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Mutably borrows from an owned value. Read more
Source§impl<F, W, T, D> Deserialize<With<T, W>, D> for F
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impl<Q, K> Equivalent<K> for Q
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impl<Q, K> Equivalent<K> for Q
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Source§fn equivalent(&self, key: &K) -> bool
fn equivalent(&self, key: &K) -> bool
Compare self to
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impl<Q, K> Equivalent<K> for Q
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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>
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impl<T> LayoutRaw for T
Source§fn layout_raw(_: <T as Pointee>::Metadata) -> Result<Layout, LayoutError>
fn layout_raw(_: <T as Pointee>::Metadata) -> Result<Layout, LayoutError>
Gets the layout of the type.
Source§impl<T> Pointable for T
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Source§impl<SS, SP> SupersetOf<SS> for SPwhere
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impl<SS, SP> SupersetOf<SS> for SPwhere
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The inverse inclusion map: attempts to construct
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The inclusion map: converts
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upcast ref
Source§fn upcast_any_mut(&mut self) -> &mut (dyn Any + 'static)
fn upcast_any_mut(&mut self) -> &mut (dyn Any + 'static)
upcast mut ref