Struct TaskCell 

pub struct TaskCell<const SIZE: usize> { /* private fields */ }

Generic, zero-allocation storage for one task’s Future state machine.

SIZE is a byte count, chosen by #[rivet::task(stack = SIZE)] (default DEFAULT_TASK_SIZE). The concrete future type is supplied only when polling, via a monomorphized generic method — this is what lets the byte size (and therefore the static declaration) be nameable without knowing the future’s real type.

Implementations

impl<const SIZE: usize> TaskCell<SIZE>

pub const fn new() -> Self

Create empty task storage.

pub fn is_completed(&self) -> bool

Whether this task’s future has completed (and been dropped). The executor uses this to skip completed tasks and track the live-task count (plan.md [B10]).

pub unsafe fn poll<F: Future<Output = ()> + 'static>( &self, init: fn() -> F, waker: &Waker, ) -> Poll<()>

Poll the task’s future, creating it on first call via init.

init is the task’s async fn, used as a zero-sized fn() -> F (so tasks currently take no arguments — shared state goes through statics, which is also the idiomatic embedded pattern for peripherals and shared queues).

Panics

Panics if F doesn’t fit in SIZE bytes or needs stricter alignment than TASK_CELL_ALIGN. Increase #[rivet::task(stack = N)] if this fires.

Safety

Must only ever be called with the same F on every invocation for a given TaskCell (true by construction: the proc macro generates one non-generic wrapper per task that always calls this with the same init function).

Trait Implementations

impl<const SIZE: usize> Default for TaskCell<SIZE>

fn default() -> Self

Returns the “default value” for a type.

impl<const SIZE: usize> Sync for TaskCell<SIZE>