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use crate::{Consumer, Iterable, IterableMap, IterableSeq};
#[must_use = "iterable adaptors are lazy and do nothing unless consumed"]
#[derive(Debug, Clone)]
pub struct LazySkipWhile<I, F> {
pub(crate) iterable: I,
pub(crate) f: F,
}
impl<I, F> Iterable for LazySkipWhile<I, F>
where
I: Iterable,
F: Fn(&I::Item) -> bool,
{
type C = I::C;
type CC<U> = I::CC<U>;
type F = I::C;
type CF<U> = I::CC<U>;
}
impl<I, F> IterableSeq for LazySkipWhile<I, F>
where
I: IterableSeq,
F: Fn(&I::Item) -> bool,
{
}
impl<K, V, I, F> IterableMap<K, V> for LazySkipWhile<I, F>
where
I: IterableMap<K, V>,
F: Fn(&(K, V)) -> bool,
{
type CCMap<X, Y> = I::CCMap<X, Y>;
}
impl<I, F> Consumer for LazySkipWhile<I, F>
where
I: Consumer,
F: Fn(&I::Item) -> bool,
{
type Item = I::Item;
type IntoIter = std::iter::SkipWhile<I::IntoIter, F>;
fn consume(self) -> Self::IntoIter {
self.iterable.consume().skip_while(self.f)
}
}
#[cfg(test)]
mod tests {
use super::*;
use crate::lazy::collect;
#[test]
fn smoke() {
let v = vec![1, 2, 3];
let res = collect(v.lazy_skip_while(|i| i < &3));
assert_eq!(res, vec![3]);
}
}