50 lines
1.1 KiB
Rust
50 lines
1.1 KiB
Rust
enum DropOption<T> {
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Some(T),
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None,
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}
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impl<T> Drop for DropOption<T> {
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fn drop(&mut self) {}
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}
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// Dropping opt could access the value behind the reference,
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fn drop_enum(opt: DropOption<&mut i32>) -> Option<&mut i32> {
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match opt {
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DropOption::Some(&mut ref mut r) => { //~ ERROR
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Some(r)
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},
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DropOption::None => None,
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}
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}
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fn optional_drop_enum(opt: Option<DropOption<&mut i32>>) -> Option<&mut i32> {
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match opt {
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Some(DropOption::Some(&mut ref mut r)) => { //~ ERROR
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Some(r)
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},
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Some(DropOption::None) | None => None,
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}
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}
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// Ok, dropping opt doesn't access the reference
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fn optional_tuple(opt: Option<(&mut i32, String)>) -> Option<&mut i32> {
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match opt {
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Some((&mut ref mut r, _)) => {
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Some(r)
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},
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None => None,
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}
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}
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// Ok, dropping res doesn't access the Ok case.
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fn different_variants(res: Result<&mut i32, String>) -> Option<&mut i32> {
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match res {
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Ok(&mut ref mut r) => {
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Some(r)
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},
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Err(_) => None,
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}
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}
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fn main() {}
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