Struct TaskGraph 

pub struct TaskGraph<T: Clone + Send + 'static> { /* private fields */ }

A directed acyclic graph of tasks with automatic parallel execution.

Tasks are added via add_task and executed via execute. Independent tasks (those whose dependencies are all satisfied) run concurrently on OS threads.

T must be Clone + Send + 'static so that results can be shared between threads and stored in the result map.

Implementations

impl<T: Clone + Send + 'static> TaskGraph<T>

pub fn new() -> Self

Create an empty task graph.

pub fn len(&self) -> usize

Number of tasks in the graph.

pub fn is_empty(&self) -> bool

Returns true if the graph contains no tasks.

pub fn contains_task(&self, name: &str) -> bool

Returns true if the graph contains a task with the given name.

pub fn dependencies(&self, name: &str) -> Option<&[String]>

Get the dependency names for a task.

pub fn add_task<F>( &mut self, name: &str, deps: &[&str], func: F, ) -> TaskGraphResult<()>

where F: FnOnce(&HashMap<String, T>) -> TaskGraphResult<T> + Send + 'static,

Add a task to the graph.

• name: unique identifier for the task.
• deps: names of tasks that must complete before this one.
• func: closure receiving a map of completed dependency results.

Errors

• CoreError::ValueError if name is already taken.
• CoreError::ValueError if any dependency name is not yet registered.
• CoreError::ComputationError if adding this task would create a cycle.

pub fn execute(self) -> TaskGraphResult<HashMap<String, T>>

Execute all tasks in the graph, respecting dependencies.

Tasks at the same dependency level run concurrently on OS threads. Returns a map from task name to result.

Errors

• If a task closure returns an error, execution continues for independent tasks but dependent tasks will not run.
• Returns the first error encountered.

pub fn execute_partial(self) -> TaskGraphResult<HashMap<String, T>>

Execute the graph and return only successfully completed results, ignoring failures (partial execution).

Unlike execute, this never returns an error for task failures. Tasks with unsatisfied dependencies are silently skipped.

pub fn execution_order(&self) -> Vec<String>

Return a topological ordering of task names.

Useful for debugging or inspection.

pub fn execution_levels(&self) -> Vec<Vec<String>>

Return task names grouped by execution level.

Tasks within the same level can execute concurrently.

Trait Implementations

impl<T: Clone + Send + 'static> Default for TaskGraph<T>

fn default() -> Self

Returns the “default value” for a type.