mirror of https://github.com/rust-lang/rust
22 lines
407 B
Rust
22 lines
407 B
Rust
//@ run-pass
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fn mut_head_tail<'a, A>(v: &'a mut [A]) -> Option<(&'a mut A, &'a mut [A])> {
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match *v {
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[ref mut head, ref mut tail @ ..] => {
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Some((head, tail))
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}
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[] => None
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}
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}
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fn main() {
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let mut v = [1,2,3,4];
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match mut_head_tail(&mut v) {
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None => {},
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Some((h,t)) => {
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*h = 1000;
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t.reverse();
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}
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}
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}
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