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// -----------------------------------------------------------------------------
// This file is generated by `cargo run -p codegen -- --unsigned`.
// Do not edit manually.
// -----------------------------------------------------------------------------
#[cfg(test)]
mod tests;
use std::sync::Arc;
use int_interval::U64CO;
/// Read-only canonical interval set for `U64CO`.
///
/// A `U64COSet` stores a normalized collection of half-open `U64CO` intervals:
///
/// - intervals are sorted by `start`;
/// - intervals are non-overlapping;
/// - adjacent intervals are merged;
/// - all queries are performed against the sealed immutable array.
///
/// Construction is intentionally restricted. Use `U64COSetBuilder` for normal
/// construction.
pub mod set {
use super::*;
/// Immutable canonical interval set.
///
/// Internally this is an `Arc<[U64CO]>`, so cloning a `U64COSet` is cheap.
///
/// Canonical invariant:
///
/// ```text
/// for every adjacent pair a, b:
/// a.end_excl() < b.start()
/// ```
///
/// The strict `<` means both overlap and adjacency have already been merged.
#[repr(transparent)]
#[derive(Clone, Debug, Eq, PartialEq)]
pub struct U64COSet {
intervals: Arc<[U64CO]>,
}
// ------------------------------------------------------------
// basic api: construction / accessors
// ------------------------------------------------------------
mod basic {
use super::*;
impl U64COSet {
/// Builds a set from an already canonical interval vector.
///
/// # Safety
///
/// The caller must guarantee that `intervals` is canonical:
///
/// - intervals are sorted by ascending `start`;
/// - intervals are non-overlapping;
/// - contiguous intervals have already been merged;
/// - therefore, for every adjacent pair `a, b`,
/// `a.end_excl() < b.start()` holds.
///
/// Violating this invariant can make binary-search based queries
/// return incorrect results.
#[inline]
pub(in crate::u64) unsafe fn new_unchecked(intervals: Vec<U64CO>) -> Self {
debug_assert!(Self::is_canonical(&intervals));
Self {
intervals: Arc::from(intervals.into_boxed_slice()),
}
}
/// Checks the canonical invariant used by binary-search queries.
///
/// `U64CO` itself already guarantees single-interval validity. This
/// function only checks the relationship between adjacent intervals.
#[inline]
fn is_canonical(intervals: &[U64CO]) -> bool {
intervals.windows(2).all(|w| w[0].end_excl() < w[1].start())
}
}
impl U64COSet {
/// Returns the number of canonical intervals.
///
/// For the `U64CO` domain, the maximum canonical interval count is
/// 128, e.g. `[0, 1), [2, 3), ..., [254, 255)`.
#[inline]
pub fn interval_count(&self) -> u64 {
self.intervals.len() as u64
}
/// Returns whether the set contains no intervals.
#[inline]
pub fn is_empty(&self) -> bool {
self.intervals.is_empty()
}
/// Returns the canonical interval slice.
///
/// The returned slice is sorted, non-overlapping, and contains no
/// adjacent intervals.
#[inline]
pub fn as_slice(&self) -> &[U64CO] {
&self.intervals
}
/// Iterates over canonical intervals by value.
#[inline]
pub fn iter_intervals(&self) -> impl Iterator<Item = U64CO> {
self.intervals.iter().copied()
}
}
}
// ------------------------------------------------------------
// predicate api: yes/no queries
// ------------------------------------------------------------
mod predicates {
use super::*;
impl U64COSet {
/// Returns whether `x` is covered by any interval in the set.
///
/// Complexity: `O(log n)`.
#[inline]
pub fn contains_point(&self, x: u64) -> bool {
let i = self.intervals.partition_point(|iv| iv.start() <= x);
i != 0 && self.intervals[i - 1].contains(x)
}
/// Returns whether `query` is fully contained by one interval.
///
/// Since the set is canonical, a contained query interval can only
/// be contained by the interval immediately preceding or starting
/// at `query.start()`.
///
/// Complexity: `O(log n)`.
#[inline]
pub fn contains_interval(&self, query: U64CO) -> bool {
let i = self
.intervals
.partition_point(|iv| iv.start() <= query.start());
i != 0 && self.intervals[i - 1].contains_interval(query)
}
/// Returns whether `query` intersects any interval in the set.
///
/// Complexity: `O(log n)`.
#[inline]
pub fn intersects_interval(&self, query: U64CO) -> bool {
let i = self
.intervals
.partition_point(|iv| iv.end_excl() <= query.start());
self.intervals.get(i).is_some_and(|iv| iv.intersects(query))
}
}
}
// ------------------------------------------------------------
// search api: returning matched intervals
// ------------------------------------------------------------
mod search {
use super::*;
/// Point-based search APIs.
mod point {
use super::*;
impl U64COSet {
/// Returns the unique interval containing `x`, if any.
///
/// Because the set is canonical, at most one interval can
/// contain a single point.
///
/// Complexity: `O(log n)`.
#[inline]
pub fn interval_containing_point(&self, x: u64) -> Option<U64CO> {
let i = self.intervals.partition_point(|iv| iv.start() <= x);
if i == 0 {
return None;
}
let iv = self.intervals[i - 1];
iv.contains(x).then_some(iv)
}
}
}
/// Interval-based search APIs.
mod interval {
use super::*;
impl U64COSet {
/// Iterates over all canonical intervals intersecting `query`.
///
/// The iterator yields original intervals stored in the set,
/// not clipped intersection segments.
///
/// Complexity: `O(log n + k)`, where `k` is the number of
/// returned intervals.
#[inline]
pub fn intervals_intersecting(&self, query: U64CO) -> impl Iterator<Item = U64CO> {
let i = self
.intervals
.partition_point(|iv| iv.end_excl() <= query.start());
self.intervals[i..]
.iter()
.copied()
.take_while(move |iv| iv.start() < query.end_excl())
}
/// Iterates over clipped intersection segments with `query`.
///
/// Example:
///
/// ```text
/// set: [10, 20), [30, 40)
/// query: [15, 35)
/// out: [15, 20), [30, 35)
/// ```
///
/// Complexity: `O(log n + k)`, where `k` is the number of
/// intersecting intervals.
#[inline]
pub fn intersections(&self, query: U64CO) -> impl Iterator<Item = U64CO> {
self.intervals_intersecting(query)
.filter_map(move |iv| iv.intersection(query))
}
}
}
}
// ------------------------------------------------------------
// coverage api: covered length / uncovered length / ratio
// ------------------------------------------------------------
mod coverage {
use super::*;
impl U64COSet {
/// Returns the covered length inside `query`.
///
/// Since `U64COSet` is canonical, all intersection segments are
/// disjoint, so summing their lengths is valid.
///
/// The result is always `<= query.len()`.
#[inline]
pub fn covered_len(&self, query: U64CO) -> u64 {
self.intersections(query).map(|iv| iv.len()).sum()
}
/// Returns the uncovered length inside `query`.
#[inline]
pub fn uncovered_len(&self, query: U64CO) -> u64 {
query.len() - self.covered_len(query)
}
/// Returns `covered_len(query) / query.len()` as `f32`.
///
/// `query.len()` is non-zero because `U64CO` cannot represent an
/// empty interval.
#[inline]
pub fn coverage_ratio(&self, query: U64CO) -> f32 {
self.covered_len(query) as f32 / query.len() as f32
}
}
}
}
/// Concurrent builder for `U64COSet`.
///
/// The builder accepts concurrent inserts into a skip list. During `seal`,
/// raw intervals are scanned in sorted order and merged into a canonical
/// immutable `U64COSet`.
pub mod builder {
use std::cmp::Ordering;
use crossbeam_skiplist::SkipSet;
use super::set::U64COSet;
use super::*;
/// Private ordering key for storing `U64CO` inside `SkipSet`.
///
/// `U64CO` does not need to implement `Ord` in its own crate. This wrapper
/// defines the ordering locally:
///
/// ```text
/// (start, end_excl)
/// ```
///
/// Because this is a set key, duplicate identical intervals are naturally
/// deduplicated during the build phase. That is correct for interval-set
/// semantics.
#[repr(transparent)]
#[derive(Copy, Clone, Debug, Eq, PartialEq)]
struct Key(U64CO);
impl Ord for Key {
#[inline]
fn cmp(&self, other: &Self) -> Ordering {
self.0
.start()
.cmp(&other.0.start())
.then_with(|| self.0.end_excl().cmp(&other.0.end_excl()))
}
}
impl PartialOrd for Key {
#[inline]
fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
Some(self.cmp(other))
}
}
/// Concurrent write-side builder for `U64COSet`.
///
/// Insertions are expected `O(log n)` through `crossbeam_skiplist`.
/// No merging is performed during insertion; normalization happens once
/// in `seal`.
#[repr(transparent)]
#[derive(Debug, Default)]
pub struct U64COSetBuilder {
raw: SkipSet<Key>,
}
impl U64COSetBuilder {
/// Creates an empty builder.
#[inline]
pub fn new() -> Self {
Self::default()
}
/// Inserts one interval into the builder.
///
/// This method is safe to call concurrently through shared references.
/// Identical intervals are deduplicated by the underlying `SkipSet`.
#[inline]
pub fn insert(&self, iv: U64CO) {
self.raw.insert(Key(iv));
}
/// Consumes the builder and returns a canonical immutable set.
///
/// The merge process is linear over the sorted skip-list iterator:
///
/// - maintain one pending interval `cur`;
/// - if the next interval overlaps or is adjacent, replace `cur` with
/// its convex hull;
/// - otherwise, push `cur` and start a new pending interval;
/// - finally, push the last pending interval.
pub fn seal(self) -> U64COSet {
let mut iter = self.raw.iter().map(|entry| entry.value().0);
let Some(mut cur) = iter.next() else {
// SAFETY:
// The empty interval list is canonical.
return unsafe { U64COSet::new_unchecked(Vec::new()) };
};
let mut out = Vec::new();
for iv in iter {
if cur.is_contiguous_with(iv) {
cur = cur.convex_hull(iv);
} else {
out.push(cur);
cur = iv;
}
}
out.push(cur);
// SAFETY:
// `self.raw` iterates keys in ascending `(start, end_excl)` order.
// The loop maintains one pending merged interval `cur`.
//
// If `iv` is contiguous with or overlaps `cur`, both are replaced
// by their convex hull, so no overlap or adjacency is emitted.
//
// If `iv` is disjoint from `cur`, then sorted order plus the failed
// contiguity test imply `cur.end_excl() < iv.start()`. Pushing
// `cur` therefore preserves the canonical invariant.
//
// After the loop, the final pending interval is pushed. Therefore
// `out` is sorted, non-overlapping, and contains no adjacent
// intervals.
unsafe { U64COSet::new_unchecked(out) }
}
}
}