Enum ExecutionStep 

pub enum ExecutionStep {
    ExecuteChild(usize, DonePredicate),
    Done(ArrayRef),
}

The result of a single execution step on an array encoding.

Instead of recursively executing children, encodings return an ExecutionStep that tells the scheduler what to do next. This enables the scheduler to manage execution iteratively using an explicit work stack, run cross-step optimizations, and cache shared sub-expressions.

Variants

ExecuteChild(usize, DonePredicate)

Request that the scheduler execute child at the given index, using the provided DonePredicate to determine when the child is “done”, then replace the child in this array and re-enter execution.

Between steps, the scheduler runs reduce/reduce_parent rules to fixpoint, enabling cross-step optimization (e.g., pushing scalar functions through newly-decoded children).

Use ExecutionStep::execute_child instead of constructing this variant directly.

Done(ArrayRef)

Execution is complete. The result may be in any encoding — not necessarily canonical. The scheduler will continue executing the result if it has not yet reached the target form.

Implementations

impl ExecutionStep

pub fn execute_child<M: Matcher>(child_idx: usize) -> Self

Request execution of child at child_idx until it matches the given Matcher.

pub fn done(result: ArrayRef) -> Self

Signal that execution is complete with the given result.

Trait Implementations

impl Debug for ExecutionStep

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

Formats the value using the given formatter.