Struct CompletableTask

pub struct CompletableTask<T> { /* private fields */ }

A CompletableTask is a one-time-use shuttle struct to enable tasks/threads to provide the result of an compute operation. Once the task is completed, any additional attempts to complete the task results in an error.

This is thread-safe equivalent to OnceCell<T>, but combines the ability to block the current thread until the task completes.

Implementations

impl<T> CompletableTask<T>

pub fn new() -> CompletableTask<T>

Creates a new CompletableTask

pub fn try_complete(&self, value: T) -> Result<(), T>

Attempt to complete this task with the specified value.

Returns Ok(()) if the task was successfully completed. Returns Err(value) with the provided value if:

• The task has already completed
• Any errors in locking or mutex poisoning prevented the completion

pub fn is_complete(&self) -> Result<bool, TaskError>

Checks if the task has been completed.

• Returns Ok(true) if the task has been completed
• Returns Ok(false) if the task has NOT been completed
• Returns Err(()) if any errors in locking prevented the checks

pub fn try_take(&self) -> Result<Poll<T>, TaskError>

Gets the result of the operation if it has been set. Does NOT block until the task is complete. Use CompletableTask::take_blocking for blocking requests.

Returns Ok(Poll::Ready(T)) if the task has been completed Returns Ok(Poll::Pending)) if the task has NOT been completed Returns Err(()) if the underlying mutex has been poisoned and is corrupt.

pub fn take_blocking(&self) -> Result<T, TaskError>

Gets the result of the operation, blocking until the operation is complete.

Returns Ok(T) if the operation completed, Returns Err(()) if any error happens.

Trait Implementations

impl<T: Clone> Clone for CompletableTask<T>

fn clone(&self) -> CompletableTask<T>

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<T> Default for CompletableTask<T>

fn default() -> Self

Returns the “default value” for a type.

impl<T> Future for CompletableTask<T>

type Output = Result<T, TaskError>

The type of value produced on completion.

fn poll(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output>

Attempts to resolve the future to a final value, registering the current task for wakeup if the value is not yet available.