rangeboundsmap

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This crate provides [RangeBoundsMap] and [RangeBoundsSet], Data Structures for storing non-overlapping intervals based of [BTreeMap].

Example using [Range]s

```rust use rangeboundsmap::RangeBoundsMap;

let mut map = RangeBoundsMap::new();

map.insertstrict(0..5, true); map.insertstrict(5..10, false);

asserteq!(map.overlaps(&(-2..12)), true); asserteq!(map.containspoint(&20), false); asserteq!(map.contains_point(&5), true); ```

Example using a custom [RangeBounds] type

```rust use std::ops::{Bound, RangeBounds};

use rangeboundsmap::RangeBoundsMap;

[derive(Debug)]

enum Reservation { // Start, End (Inclusive-Inclusive) Finite(u8, u8), // Start (Exclusive) Infinite(u8), }

// First, we need to implement RangeBounds impl RangeBounds for Reservation { fn startbound(&self) -> Bound<&u8> { match self { Reservation::Finite(start, _) => { Bound::Included(start) } Reservation::Infinite(start) => { Bound::Excluded(start) } } } fn endbound(&self) -> Bound<&u8> { match self { Reservation::Finite(, end) => Bound::Included(end), Reservation::Infinite() => Bound::Unbounded, } } }

// Next we can create a custom typed RangeBoundsMap let reservationmap = RangeBoundsMap::tryfrom([ (Reservation::Finite(10, 20), "Ferris".tostring()), (Reservation::Infinite(20), "Corro".tostring()), ]) .unwrap();

for (reservation, name) in reservation_map.overlapping(&(16..17)) { println!( "{name} has reserved {reservation:?} inside the range 16..17" ); }

for (reservation, name) in reservation_map.iter() { println!("{name} has reserved {reservation:?}"); }

asserteq!( reservationmap.overlaps(&Reservation::Infinite(0)), true ); ```

Key Definitions:

Invalid Ranges

Within this crate, not all ranges are considered valid ranges. The definition of the validity of a range used within this crate is that a range is only valid if it contains at least one value of the underlying domain.

For example, 4..6 is considered valid as it contains the values 4 and 5, however, 4..4 is considered invalid as it contains no values. Another example of invalid range are those whose start values are greater than their end values. such as 5..2 or 100..=40.

Here are a few examples of ranges and whether they are valid:

| range | valid | | -------------- | ----- | | 0..=0 | YES | | 0..0 | NO | | 0..1 | YES | | 9..8 | NO | | (0.4)..=(-0.2) | NO | | ..(-3) | YES | | 0.0003.. | YES | | .. | YES | | 400..=400 | YES |

Overlap

Two ranges are "overlapping" if there exists a point that is contained within both ranges.

Touching

Two ranges are "touching" if they do not overlap and there exists no value between them. For example, 2..4 and 4..6 are touching but 2..4 and 6..8 are not, neither are 2..6 and 4..8.

Merging

When a range "merges" other ranges it absorbs them to become larger.

Further Reading

See Wikipedia's article on mathematical Intervals: https://en.wikipedia.org/wiki/Interval_(mathematics)

Improvements/Caveats

Credit

I originally came up with the StartBound: [Ord] bodge on my own, however, I later stumbled across [rangemap] which also used a StartBound: [Ord] bodge. [rangemap] then became my main source of inspiration.

Later I then undid the [Ord] bodge and switched to my own full-code port of [BTreeMap], inspired and forked from [copse], for it's increased flexibility.

Origin

The aim for this library was to become a more generic superset of [rangemap], following from this issue and this pull request in which I changed [rangemap]'s [RangeMap] to use [RangeBounds]s as keys before I realized it might be easier and simpler to just write it all from scratch.

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