slimvec 0.4.9

Dynamic array with a smaller inline-size
Documentation 
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// Copyright © ickk, 2026

use ::core::{
  mem,
  ops::{Bound, Range, RangeBounds},
};

/// Internal trait used for specialisation
pub(crate) trait TypeMeta {
  /// This is `true` when `T` is a zero-sized-type. It is used to specialise
  /// the implementation so that [`RawSlimVec`]s containing ZST elements never
  /// allocate.
  const IS_ZST: bool;
}

impl<T> TypeMeta for T {
  const IS_ZST: bool = mem::size_of::<T>() == 0;
}

/// Conform `RangeBounds` to a `Range<usize>` bounded between `0..max`
///
/// # Panics
///
/// - Panics if `range.start_bound()` is greater than `range.end_bound()`.
/// - Panics if `range.end_bound()` is greater than `max`.
#[inline]
pub(crate) fn conform_range(
  range: impl RangeBounds<usize>,
  max: usize,
) -> Range<usize> {
  let end = match range.end_bound() {
    Bound::Excluded(&b) if b <= max => Some(b),
    Bound::Included(&b) if b < max => Some(b + 1),
    Bound::Unbounded => Some(max),
    _ => None,
  };
  let start = match range.start_bound() {
    Bound::Included(&b) if Some(b) <= end => Some(b),
    Bound::Excluded(&b) if Some(b) < end => Some(b + 1),
    Bound::Unbounded => Some(0),
    _ => None,
  };
  let (Some(start), Some(end)) = (start, end) else {
    panic!("invalid range")
  };
  start..end
}