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