Struct MergeOrderedHook 

pub struct MergeOrderedHook<T, B: Boundedness = Unbounded> { /* private fields */ }

A hook handle controlling a merge_ordered operator over streams of T elements.

The operator preserves the order of each input while interleaving the two inputs non-deterministically. A top-level decision releases the front element of one input’s buffer; inside a tick, a single decision supplies the complete interleaving. See hydro_lang::sim::hooks for the decisions offered.

Implementations

impl<T> MergeOrderedHook<T, Unbounded>

where T: Serialize + DeserializeOwned,

pub fn next_first(&self, value: T) -> DecisionFuture

Available on crate feature sim only.

Scripts a top-level merge_ordered action to release the front element of the first input’s buffer, which must equal value (per-input order is preserved, so a mismatch panics). Exactly one element is released, preserving opportunities for ticks and feedback to interleave with the remaining buffered input.

pub fn next_second(&self, value: T) -> DecisionFuture

Available on crate feature sim only.

Scripts a top-level merge_ordered action to release the front element of the second input’s buffer, which must equal value; see Self::next_first.

pub fn advance_first(&self) -> DecisionFuture

Available on crate feature sim only.

Scripts a top-level merge_ordered action to release the front element of the first input’s buffer, whatever it is (waiting for one to arrive if that input is empty). Unlike Self::next_first, this does not assert the released value; use next_first(value) to name it exactly and fail loudly on mis-synchronization.

pub fn advance_second(&self) -> DecisionFuture

Available on crate feature sim only.

Scripts a top-level merge_ordered action to release the front element of the second input’s buffer, whatever it is; see Self::advance_first.

pub fn pause(&self)

Available on crate feature sim only.

Declares that buffering at this operator is intended: while paused, the hook is exempt from the missing-decision error, never causes its tick to run, and — if its tick runs anyway because other hooks feed it — contributes its “nothing new” behavior each time. Scripting any decision implicitly resumes the hook.

A pause takes its place in the script like everything else: requested while a decision is still pending, the hold begins once that decision has been consumed.

pub fn resume(&self)

Available on crate feature sim only.

Ends a Self::pause (and clears Self::auto_pause mode).

pub fn auto_pause(&self)

Available on crate feature sim only.

Sets a standing mode where this hook only ever acts when scripted: it holds immediately, and every scripted decision leaves a fresh hold in place behind it.

This deliberately opts out of the forgotten-hook protection: if the test forgets a step, the operator silently holds its data instead of failing. The one auto_pause() line at the top of a test is the reviewer-visible marker that this hook’s timing is entirely script-driven, missed steps and all.

pub async fn pause_while<Fut: Future>(&self, body: Fut) -> Fut::Output

Available on crate feature sim only.

Pauses the hook exactly for the duration of body (resuming even on panic), so a bracketed buffering phase cannot leak a paused hook.

pub fn pause_until( &self, predicate: impl Fn(&MergeStatus) -> bool + Unpin, ) -> PauseUntilFuture<MergeStatus, impl Fn(&MergeStatus) -> bool + Unpin>

Available on crate feature sim only.

Pauses the hook and returns a future that resolves once the hook’s pending-input status satisfies predicate — a synchronization point for scripts where the right decision is not knowable upfront. The status is read on demand at every scheduling point. After the future resolves, the hook is unpaused; the ordinary missing-decision error applies from there on.

pub fn pause_until_count( &self, n: usize, ) -> PauseUntilFuture<MergeStatus, impl Fn(&MergeStatus) -> bool + Unpin>

Available on crate feature sim only.

Pauses a top-level merge hook until at least n elements are buffered (in total, across both inputs); see Self::pause_until.

impl<T> MergeOrderedHook<T, Bounded>

where T: Serialize + DeserializeOwned,

pub fn order( &self, values: impl IntoIterator<Item = (bool, T)>, ) -> DecisionFuture

Available on crate feature sim only.

Scripts an in-tick merge_ordered observation to consume its complete input in exactly this interleaving, with each value labeled by the input it is drawn from (false = first/left, true = second/right). Each input’s labeled values must be exactly that input’s tick-local batch, in order.

Trait Implementations

impl<T, B: Boundedness> Clone for MergeOrderedHook<T, B>

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl<T, B: Boundedness> Copy for MergeOrderedHook<T, B>

impl<T, B: Boundedness> Debug for MergeOrderedHook<T, B>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<T, B: Boundedness> SimHook for MergeOrderedHook<T, B>

where T: Serialize + DeserializeOwned + PartialEq,

fn create(next_id: &mut dyn FnMut() -> usize) -> Self

Creates every handle in this value, allocating fresh IDs via next_id.