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mod all;
mod none;
pub use self::all::All;
pub use self::none::None;
use crate::bit_set::{BitSet, Bits};
pub fn all() -> All {
self::all::All::default()
}
pub fn none() -> None {
self::none::None::default()
}
pub trait Mask: Sized {
type Iter: Iterator<Item = usize>;
fn test(&self, index: usize) -> bool;
fn iter(&self) -> Self::Iter;
fn join<I>(&self, iter: I) -> Join<Self::Iter, I::IntoIter>
where
Self: Sized,
I: IntoIterator,
{
Join {
mask: self.iter(),
right: iter.into_iter(),
last: 0,
}
}
}
impl<T> Mask for BitSet<T>
where
T: Bits,
{
type Iter = T::Iter;
#[inline]
fn test(&self, index: usize) -> bool {
<BitSet<T>>::test(self, index)
}
#[inline]
fn iter(&self) -> Self::Iter {
<BitSet<T>>::iter(self)
}
}
pub struct Join<A, B> {
mask: A,
right: B,
last: usize,
}
impl<A, B> Iterator for Join<A, B>
where
A: Iterator<Item = usize>,
B: Iterator,
{
type Item = B::Item;
fn next(&mut self) -> Option<Self::Item> {
let index = self.mask.next()?;
let offset = index - self.last;
let buf = self.right.nth(offset)?;
self.last = index + 1;
Some(buf)
}
}