17 lines
440 B
Rust
17 lines
440 B
Rust
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// exec-env:RUST_POISON_ON_FREE=1
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fn main() {
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let x: @mut @option<~int> = @mut @none;
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alt x {
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@@some(y) {
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// here, the refcount of `*x` is bumped so
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// `y` remains valid even if `*x` is modified.
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*x = @none;
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}
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@@none {
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// here, no bump of the ref count of `*x` is needed, but in
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// fact a bump occurs anyway because of how pattern marching
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// works.
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}
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}
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}
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