Struct TaskGraph 

pub struct TaskGraph { /* private fields */ }

DAG of tasks with dependency tracking. Maintains an in-degree counter so ready_tasks() is O(1) amortized.

Implementations

impl TaskGraph

pub fn new() -> Self

pub fn add(&mut self, task: RuntimeTask, dependencies: Vec<usize>) -> usize

Add a task, returns its ID. Duplicate dependency entries are collapsed: in_degree counts entries but complete decrements once per completed dependency, so a duplicated entry would leave the node permanently below its own in-degree (a silent stall).

pub fn topological_sort(&self) -> Result<Vec<usize>>

Topological sort — returns ordered IDs or error if cycle detected.

pub fn ready_tasks(&self) -> Vec<usize>

Return IDs of tasks that are Ready (deps satisfied, not yet started).

pub fn start(&mut self, task_id: usize)

Mark a task as running.

pub fn set_ready(&mut self, task_id: usize)

Re-mark a (running) task as Ready without touching dependents — used to re-arm a loop node for its next iteration. Unlike complete, this does NOT decrement any in-degree, so the loop node’s dependents stay pending until the loop finally completes.

pub fn complete(&mut self, task_id: usize, result: LoopResult)

Mark a task as completed; promote dependents whose in-degree reaches 0.

Idempotent: a task already terminal (Completed/Failed) is left untouched — a duplicate completion (at-least-once event delivery, resume replay) must not double-decrement its dependents’ in-degree, which would underflow (debug panic) or over-promote gated nodes.

pub fn fail(&mut self, task_id: usize)

Mark a task as failed (dependents remain Pending — caller decides policy). Terminal states are sticky: failing an already-completed task must not un-complete it (idempotency twin of complete).

pub fn get(&self, task_id: usize) -> Option<&TaskNode>

pub fn len(&self) -> usize

pub fn is_empty(&self) -> bool

pub fn all_done(&self) -> bool

Trait Implementations

impl Default for TaskGraph

fn default() -> Self

Returns the “default value” for a type.