52 lines
1.0 KiB
Rust
52 lines
1.0 KiB
Rust
use core::mem;
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use core::mem::MaybeUninit;
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pub struct OnDrop<F: FnOnce()> {
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f: MaybeUninit<F>,
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}
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impl<F: FnOnce()> OnDrop<F> {
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pub fn new(f: F) -> Self {
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Self {
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f: MaybeUninit::new(f),
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}
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}
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pub fn defuse(self) {
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mem::forget(self)
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}
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}
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impl<F: FnOnce()> Drop for OnDrop<F> {
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fn drop(&mut self) {
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unsafe { self.f.as_ptr().read()() }
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}
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}
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/// An explosive ordinance that panics if it is improperly disposed of.
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///
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/// This is to forbid dropping futures, when there is absolutely no other choice.
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///
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/// To correctly dispose of this device, call the [defuse](struct.DropBomb.html#method.defuse)
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/// method before this object is dropped.
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pub struct DropBomb {
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_private: (),
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}
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impl DropBomb {
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pub fn new() -> Self {
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Self { _private: () }
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}
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/// Defuses the bomb, rendering it safe to drop.
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pub fn defuse(self) {
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mem::forget(self)
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}
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}
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impl Drop for DropBomb {
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fn drop(&mut self) {
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panic!("boom")
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}
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}
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