Overview

The h8io.stages.operators package holds the stages that wrap other stages. Each applies its inner stage once per run — for the operators that drive a whole cycle of it instead, see cycles.

Decorators

A decorator wraps one stage and keeps its type: an Alterator whose evolution is mapped so that the wrapping survives into the next generation.

Operator	What it changes
CompleteIfNone	turns a Yield.None with Success into one with Status.Complete
KeepLastOutput	re-emits the last output when the inner stage yields none
Lift	wraps the optional output into an Option, so a value is always produced
Safe	catches non-fatal exceptions and reports them as errors
LocalSoftDeadline	completes the run once the current unit of work is out of time

Binary Operators

These take two stages over a shared input and combine what both produced — see BinaryOperator for the shape they share.

Operator	Output	Right side
And	(LO, RO)	skipped when the left yields nothing
IAnd	(LO, RO)	always applied
Or	Either[LO, RO]	applied only when the left yields nothing

The inclusive-or of the family, IOr, lives in the stages-cats module, since its output type is cats.data.Ior.

Decorations

Identity and CompleteIfSome are not stages but Decorations — functions from a stage to a stage. Identity returns it untouched; CompleteIfSome appends Complete after it with ~>. Both are singletons with a typed apply[I, O, E], so they can be passed wherever a decoration is expected without allocating one.