Struct TrialContext 

pub struct TrialContext { /* private fields */ }

Handle passed to a trial: reports intermediate metrics and asks whether the pruner wants the trial stopped.

report is the single channel for per-step metrics: it records the value on the trial, emits Event::TrialMetric, and — when the metric is the study’s objective — consults the pruner against the completed trials’ histories. Values are compared on a maximize scale (the runner pre-normalizes for Minimize).

The handle is cheaply cloneable (Arc-backed shared state) so it can outlive the borrow stack — e.g. cross into a Python callback.

Implementations

impl TrialContext

pub fn report(&self, name: &str, value: f64, step: usize) -> bool

Record an intermediate metric at step. Returns true when the trial should stop (pruned) — the executor should then return early; the runner marks the trial pruned regardless.

pub fn should_prune(&self) -> bool

Whether the pruner has decided to stop this trial.

pub fn metrics(&self) -> Vec<MetricRecord>

Metrics reported so far.

pub fn trial_id(&self) -> &str

Id of the trial this handle belongs to.

Trait Implementations

impl Clone for TrialContext

fn clone(&self) -> TrialContext

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.