StepMount class

Everything the registry's CapabilityRegistry.host needs to mount one eligible CapabilityStep as an engine leaf.

Slimmed 2026-07-02 (the context rip-out): the work Bead and the session SiblingView are AMBIENT (mounted by WorkBead/SessionScope) — an effect reads them with the non-binding lookup, so the mount threads only the step's own identity + supervision params.

Constructors

StepMount({required CapabilityStep step, required String nodePath, required Circuit circuit, required String circuitPath, required SessionHandle session, required NodeCursor node, required Key key, int circuitRound = 0, Backoff backoff = Backoff.standard, int maxRestarts = 3, PersistedFailureEvidence? adoptedFailure, AdoptedFailureLatch? onAdoptedLatch})
Bundles the step, its full nodePath, the circuit it is a member of (+ that circuit's own circuitPath), the resolved session, the step's current node cursor (identity/incarnation for respawn — D-4), the incarnation-keyed reconcile key, and the owning circuit's supervision params (backoff/maxRestarts) the host uses to author the supervised-restart cursor on failure (D-5).
const

Properties

adoptedFailure → PersistedFailureEvidence?
Durable failure evidence that adoption must re-evaluate through the same per-kind policy path a live host uses. Null on every ordinary mount.
final
backoff → Backoff
The owning circuit's backoff schedule (D-5) — the host computes the cooldown for the next restart attempt from it on failure.
final
circuit → Circuit
The circuit this step is a MEMBER of — the graph a Rewind (tg-o90) resolves its named siblings + their transitive dependents against. A VALUE (config in the tree, ADR-0008 D-H), threaded by the inflater that owns it; REQUIRED, because a step always belongs to a circuit and a null-branch guard that can never fire in production is exactly the ceremony ADR-0008 D3 says to delete.
final
circuitPath → String
The node path of circuit's own root, i.e. nodePath == '$circuitPath/${step.stepId}' — the prefix every rewound sibling path is built from.
final
circuitRound → int
The session circuit incarnation for this step, derived from the active step bead's supersedes-chain depth.
final
hashCode → int
The hash code for this object.
no setterinherited
key → Key
The incarnation-keyed reconcile identity (ValueKey('$nodePath#$restartCount.$rewindCount')) — a supervised restart bumps restartCount (D-5) and a routing REWIND bumps rewindCount (tg-o90); either changes the key, so keyed reconcile unmounts the old incarnation and mounts the new.
final
maxRestarts → int
The owning circuit's restart budget (D-5) — at restartCount >= maxRestarts the host writes the exhausted failure (no cooldown) and SessionScope escalates.
final
node → NodeCursor
The step's current cursor entry (drives respawn-or-skip + the incarnation).
final
nodePath → String
The step's FULL path within the circuit tree ('$parentNodePath/$stepId') — the cursor key + the per-step provider-name segment.
final
onAdoptedLatch → AdoptedFailureLatch?
The existing SessionScope breaker-close seam used only when the shared policy returns ExhaustionBehavior.latchFailed.
final
runtimeType → Type
A representation of the runtime type of the object.
no setterinherited
session → SessionHandle
The adopt-or-minted session this leaf writes its cursor onto.
final
step → CapabilityStep
The eligible step to mount.
final

Methods

noSuchMethod(Invocation invocation) → dynamic
Invoked when a nonexistent method or property is accessed.
inherited
toString() → String
A string representation of this object.
inherited

Operators

operator ==(Object other) → bool
The equality operator.
inherited