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//@ compile-flags: -Zvalidate-mir -C opt-level=3
//@ build-pass
#![feature(let_chains)]
struct TupleIter<T, I: Iterator<Item = T>> {
inner: I,
}
impl<T, I: Iterator<Item = T>> Iterator for TupleIter<T, I> {
type Item = (T, T, T);
fn next(&mut self) -> Option<Self::Item> {
let inner = &mut self.inner;
if let Some(first) = inner.next()
&& let Some(second) = inner.next()
&& let Some(third) = inner.next()
{
Some((first, second, third))
} else {
None
}
}
}
fn main() {
let vec: Vec<u8> = Vec::new();
let mut tup_iter = TupleIter {
inner: vec.into_iter(),
};
tup_iter.next();
}
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