pub struct Spawn<T: ?Sized> { /* private fields */ }
Expand description

Representation of a spawned future/stream.

This object is returned by the spawn function in this module. This represents a “fused task and future”, storing all necessary pieces of a task and owning the top-level future that’s being driven as well.

A Spawn can be poll’d for completion or execution of the current thread can be blocked indefinitely until a notification arrives. This can be used with either futures or streams, with different methods being available on Spawn depending which is used.

Implementations

Waits for the internal future to complete, blocking this thread’s execution until it does.

This function will call poll_future in a loop, waiting for the future to complete. When a future cannot make progress it will use thread::park to block the current thread.

Like wait_future, except only waits for the next element to arrive on the underlying stream.

Blocks the current thread until it’s able to send value on this sink.

This function will send the value on the sink that this task wraps. If the sink is not ready to send the value yet then the current thread will be blocked until it’s able to send the value.

Blocks the current thread until it’s able to flush this sink.

This function will call the underlying sink’s poll_complete method until it returns that it’s ready, proxying out errors upwards to the caller if one occurs.

The thread will be blocked until poll_complete returns that it’s ready.

Blocks the current thread until it’s able to close this sink.

This function will close the sink that this task wraps. If the sink is not ready to be close yet, then the current thread will be blocked until it’s closed.

Get a shared reference to the object the Spawn is wrapping.

Get a mutable reference to the object the Spawn is wrapping.

Consume the Spawn, returning its inner object

Calls the provided closure, scheduling notifications to be sent to the notify argument.

Polls the internal future, scheduling notifications to be sent to the notify argument.

This method will poll the internal future, testing if it’s completed yet. The notify argument is used as a sink for notifications sent to this future. That is, while the future is being polled, any call to task::current() will return a handle that contains the notify specified.

If this function returns NotReady, then the notify should have been scheduled to receive a notification when poll can be called again. Otherwise if Ready or Err is returned, the Spawn task can be safely destroyed.

Note that notify itself is passed as a shared reference, and is itself not required to be a NotifyHandle. The Clone and Into trait bounds will be used to convert this notify to a NotifyHandle if necessary. This construction can avoid an unnecessary atomic reference count bump in some situations.

Unsafety and id

This function and all other *_notify functions on this type will treat the id specified very carefully, explicitly calling functions like the notify argument’s clone_id and drop_id functions. It should be safe to encode a pointer itself into the id specified, such as an Arc<N> or a Box<N>. The clone_id and drop_id functions are then intended to be sufficient for the memory management related to that pointer.

Like poll_future_notify, except polls the underlying stream.

Invokes the underlying start_send method with this task in place.

If the underlying operation returns NotReady then the notify value passed in will receive a notification when the operation is ready to be attempted again.

Invokes the underlying poll_complete method with this task in place.

If the underlying operation returns NotReady then the notify value passed in will receive a notification when the operation is ready to be attempted again.

Invokes the underlying close method with this task in place.

If the underlying operation returns NotReady then the notify value passed in will receive a notification when the operation is ready to be attempted again.

Trait Implementations

Formats the value using the given formatter. Read more

Auto Trait Implementations

Blanket Implementations

Gets the TypeId of self. Read more

Immutably borrows from an owned value. Read more

Mutably borrows from an owned value. Read more

Returns the argument unchanged.

Calls U::from(self).

That is, this conversion is whatever the implementation of From<T> for U chooses to do.

The type returned in the event of a conversion error.

Performs the conversion.

The type returned in the event of a conversion error.

Performs the conversion.