Struct TaskGroup 

pub struct TaskGroup { /* private fields */ }

Group of tasks to be waited on.

Implementations

impl TaskGroup

pub fn new() -> Self

Creates new task group

pub fn add(&self)

Increases the task counter by 1.

This is used to indicate an intention for an upcoming task. Call to this function should be matched by call to Self::done. If the call to done() needs to be done in a RAII manner use Self::add_work

pub fn add_n(&self, n: u32)

Increases the task counter by n.

This is used to indicate an intention for an upcoming task. Call to this function should be matched by call to Self::done. If the call to done() needs to be done in a RAII manner use Self::add_work

pub fn add_work(&self, n: u32) -> Work

Creates a work which does increment the task counter by n. The returned Work decrements the counter when dropped.

pub fn done(&self)

Decrements the task counter by 1.

pub fn done_n(&self, n: u32)

Decrements the task counter by n

pub fn wait(&self) -> WaitFuture

Returns the WaitFuture When awaited the future returns the internal counter, which can be 0 or -ve. A value can be -ve if there were more TaskGroup::done calls than TaskGroup::add. The caller can use this to maintain an invariant in case of any mis-behaving tasks.

The future when resolved also resets the internal counter to zero. The taskgroup then can be reused.

use taskwait::TaskGroup;
 
#[tokio::main]
async fn main() {
    let tg = TaskGroup::new();
     
    // ... Spawn tasks ...

    let n = tg.wait().await;
    if n < 0 {
        // Return Error
    }
}

Trait Implementations

impl Clone for TaskGroup

fn clone(&self) -> TaskGroup

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Default for TaskGroup

fn default() -> Self

Returns the “default value” for a type.