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use std::fmt::Debug;
use std::hash::Hash;
/// Represents some newtyped `usize` wrapper.
///
/// Purpose: avoid mixing indexes for different bitvector domains.
pub trait Idx: Copy + 'static + Eq + PartialEq + Debug + Hash {
fn new(idx: usize) -> Self;
fn index(self) -> usize;
#[inline]
fn increment_by(&mut self, amount: usize) {
*self = self.plus(amount);
}
#[inline]
#[must_use = "Use `increment_by` if you wanted to update the index in-place"]
fn plus(self, amount: usize) -> Self {
Self::new(self.index() + amount)
}
}
impl Idx for usize {
#[inline]
fn new(idx: usize) -> Self {
idx
}
#[inline]
fn index(self) -> usize {
self
}
}
impl Idx for u32 {
#[inline]
fn new(idx: usize) -> Self {
assert!(idx <= u32::MAX as usize);
idx as u32
}
#[inline]
fn index(self) -> usize {
self as usize
}
}