Crate ps_range 

Generalized range abstractions.

This crate provides three capability traits, alongside the concrete range types that implement them:

• RangeStart describes a range with a defined inclusive lower bound; it is the shared base of the two extension traits.
• RangeExt describes a range bounded on both ends, exposing its upper bound in both the inclusive and the exclusive form.
• PartialRangeExt describes a range that may be unbounded above or empty, exposing its upper bound losslessly through RangeEnd along with clamping and intersection operations.
• Range is a concrete bounded range whose end is either inclusive or exclusive, as recorded by RangeEnd.
• PartialRange is a concrete possibly-unbounded range that also implements Iterator.

Each trait is implemented for the standard library range types, for shared and mutable references, and for the concrete types above, wherever the type’s shape supports it. RangeStart and PartialRangeExt are also implemented for Option, with None as the empty range, so a possibly-absent range remains usable as a range. The traits’ method names are disjoint, so all three can share scope.

Operations interpret Idx as a discrete domain in which x + one is the successor of x. A bound is converted between its inclusive and exclusive forms only where the converted bound is provably representable: clamping compares bounds through RangeEnd or against window ends that are themselves representable, so an inclusive end at the maximum index value is handled faithfully, without saturation or widening.

Examples

use ps_range::{PartialRange, PartialRangeExt, RangeExt};

// Clamp a slice request to a buffer's length.
let buffer = [0u8; 10];
let requested = 4usize..;

assert_eq!(requested.clamp_right_exclusive(buffer.len()), 4..10);
assert_eq!(buffer[requested.clamp_right_exclusive(buffer.len())].len(), 6);

// Clamping requires only minimal trait bounds on the index type.
assert_eq!((..8).clamp_right(6usize), 0..6);

// Iteration eventually leaves every range exhausted.
let mut range = PartialRange::from(254u8..);

assert_eq!(range.by_ref().collect::<Vec<_>>(), vec![254, 255]);
assert_eq!(range, PartialRange::Exhausted);

Structs

Range

A range bounded on both ends, with an inclusive start and an end whose inclusivity is recorded by RangeEnd.

Enums

PartialRange

A range that may be unbounded above, empty, or exhausted.

RangeEnd

The upper bound of a Range, either inclusive or exclusive.

Traits

PartialRangeExt

A range that may be unbounded above or empty.

RangeExt

A range bounded on both ends.

RangeStart

A range with a defined inclusive lower bound.