Struct holochain::prelude::kitsune_p2p::dependencies::kitsune_p2p_types::dependencies::lair_keystore_api::dependencies::tokio::sync::mpsc::WeakSender
source · pub struct WeakSender<T> { /* private fields */ }
Expand description
A sender that does not prevent the channel from being closed.
If all Sender
instances of a channel were dropped and only WeakSender
instances remain, the channel is closed.
In order to send messages, the WeakSender
needs to be upgraded using
WeakSender::upgrade
, which returns Option<Sender>
. It returns None
if all Sender
s have been dropped, and otherwise it returns a Sender
.
#Examples
use tokio::sync::mpsc::channel;
#[tokio::main]
async fn main() {
let (tx, _rx) = channel::<i32>(15);
let tx_weak = tx.downgrade();
// Upgrading will succeed because `tx` still exists.
assert!(tx_weak.upgrade().is_some());
// If we drop `tx`, then it will fail.
drop(tx);
assert!(tx_weak.clone().upgrade().is_none());
}
Implementations§
Trait Implementations§
source§impl<T> Clone for WeakSender<T>
impl<T> Clone for WeakSender<T>
source§fn clone(&self) -> WeakSender<T>
fn clone(&self) -> WeakSender<T>
Returns a copy of the value. Read more
1.0.0 · source§fn clone_from(&mut self, source: &Self)
fn clone_from(&mut self, source: &Self)
Performs copy-assignment from
source
. Read moreAuto Trait Implementations§
impl<T> !RefUnwindSafe for WeakSender<T>
impl<T> Send for WeakSender<T>where T: Send,
impl<T> Sync for WeakSender<T>where T: Send,
impl<T> Unpin for WeakSender<T>
impl<T> !UnwindSafe for WeakSender<T>
Blanket Implementations§
§impl<T> ArchivePointee for T
impl<T> ArchivePointee for T
§type ArchivedMetadata = ()
type ArchivedMetadata = ()
The archived version of the pointer metadata for this type.
§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
fn borrow_mut(&mut self) -> &mut T
Mutably borrows from an owned value. Read more
§impl<F, W, T, D> Deserialize<With<T, W>, D> for Fwhere
W: DeserializeWith<F, T, D>,
D: Fallible + ?Sized,
F: ?Sized,
impl<F, W, T, D> Deserialize<With<T, W>, D> for Fwhere W: DeserializeWith<F, T, D>, D: Fallible + ?Sized, F: ?Sized,
§fn deserialize(
&self,
deserializer: &mut D
) -> Result<With<T, W>, <D as Fallible>::Error>
fn deserialize( &self, deserializer: &mut D ) -> Result<With<T, W>, <D as Fallible>::Error>
Deserializes using the given deserializer
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> 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> ⓘ
§impl<T> Pointable for T
impl<T> Pointable for T
§impl<SS, SP> SupersetOf<SS> for SPwhere
SS: SubsetOf<SP>,
impl<SS, SP> SupersetOf<SS> for SPwhere SS: SubsetOf<SP>,
§fn to_subset(&self) -> Option<SS>
fn to_subset(&self) -> Option<SS>
The inverse inclusion map: attempts to construct
self
from the equivalent element of its
superset. Read more§fn is_in_subset(&self) -> bool
fn is_in_subset(&self) -> bool
Checks if
self
is actually part of its subset T
(and can be converted to it).§fn to_subset_unchecked(&self) -> SS
fn to_subset_unchecked(&self) -> SS
Use with care! Same as
self.to_subset
but without any property checks. Always succeeds.§fn from_subset(element: &SS) -> SP
fn from_subset(element: &SS) -> SP
The inclusion map: converts
self
to the equivalent element of its superset.§impl<T> Upcastable for Twhere
T: Any + Send + Sync + 'static,
impl<T> Upcastable for Twhere T: Any + Send + Sync + 'static,
§fn upcast_any_ref(&self) -> &(dyn Any + 'static)
fn upcast_any_ref(&self) -> &(dyn Any + 'static)
upcast ref
§fn upcast_any_mut(&mut self) -> &mut (dyn Any + 'static)
fn upcast_any_mut(&mut self) -> &mut (dyn Any + 'static)
upcast mut ref