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use crate::{Consumer, Iterable, IterableSeq};
#[must_use = "iterable adaptors are lazy and do nothing unless consumed"]
#[derive(Debug, Clone)]
pub struct LazyCloned<I> {
pub(crate) iterable: I,
}
impl<'a, I, T> Iterable for LazyCloned<I>
where
T: 'a + Clone,
I: Iterable<Item = &'a T>,
{
type C = I::CC<T>;
type CC<U> = I::CC<U>;
type F = I::CF<T>;
type CF<U> = I::CF<U>;
}
impl<'a, I, T> IterableSeq for LazyCloned<I>
where
T: 'a + Clone,
I: IterableSeq<Item = &'a T>,
{
}
impl<'a, I, T> Consumer for LazyCloned<I>
where
T: 'a + Clone,
I: Consumer<Item = &'a T>,
{
type Item = T;
type IntoIter = std::iter::Cloned<I::IntoIter>;
fn consume(self) -> Self::IntoIter {
self.iterable.consume().cloned()
}
}
#[cfg(test)]
mod tests {
use super::*;
use crate::assert_type;
use crate::lazy::collect;
#[test]
fn smoke() {
let v = vec![&1, &2, &3];
let res = collect(v.lazy_cloned());
assert_eq!(res, vec![1, 2, 3]);
}
#[test]
fn test_f() {
let v = [&1, &2, &3];
let res = v.lazy_cloned().rev();
assert_type::<[i32; 3]>(res);
}
#[test]
fn test_cf() {
let v = [&1, &2, &3];
let res = v.lazy_cloned().map(|x| x.to_string());
assert_type::<[String; 3]>(res);
}
}