Struct ProgressToken 

pub struct ProgressToken { /* private fields */ }

A cheaply-cloneable progress token representing a portion of overall progress.

Progress is modeled as a float64 value in [0.0, 1.0]. A root token covers the full range. Calling split or subtoken subdivides this token’s range into children, which can be further subdivided recursively.

The hot path (set / fraction) is lock-free — a single atomic store or load. Structural changes (split/subtoken) and root observation (root_fraction) take a Mutex.

Example

let root = ProgressToken::new();
let subs = root.split(&[1, 2, 1]).unwrap(); // 25%, 50%, 25%
subs[0].set(1.0); // first task done  → root_fraction ≈ 0.25
subs[1].set(0.5); // second task half → root_fraction ≈ 0.50

Implementations

impl ProgressToken

pub fn new() -> ProgressToken

Create a root progress token at 0% covering the full [0.0, 1.0] range.

pub fn set(&self, fraction: f64)

Set this token’s progress fraction (clamped to [0.0, 1.0]).

Lock-free: single atomic store.

pub fn fraction(&self) -> f64

This token’s progress fraction in [0.0, 1.0].

pub fn width(&self) -> f64

This token’s width as a fraction of the root [0.0, 1.0] range.

pub fn is_complete(&self) -> bool

Whether this token’s progress is ≥ 1.0.

pub fn root_fraction(&self) -> f64

Overall progress across the entire tree: Σ(width × progress) for all intervals. Returns a value in [0.0, 1.0].

pub fn split(&self, weights: &[u32]) -> Result<Vec<ProgressToken>, CoreError>

Split this token into subtokens by relative weights.

This token’s width is set to 0 and its progress is reset. The children inherit proportional fractions of the original width.

Returns an error if weights is empty or any weight is 0.

pub fn subtoken(&self, frac_width: f64) -> ProgressToken

Create one child subtoken covering frac_width of this token’s range.

This token’s width shrinks by the amount given to the child. For example, token.subtoken(0.3) gives 30% of this token’s current width to the child.

Trait Implementations

impl Clone for ProgressToken

fn clone(&self) -> ProgressToken

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for ProgressToken

fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter.

impl Default for ProgressToken

fn default() -> ProgressToken

Returns the “default value” for a type.