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//! A drop implementation runner.

/// Runs a closure on drop.
pub struct OnDrop<F: FnOnce()> {
    f: core::mem::MaybeUninit<F>,
}

impl<F: FnOnce()> OnDrop<F> {
    /// Make a new droppper given a closure.
    pub fn new(f: F) -> Self {
        Self {
            f: core::mem::MaybeUninit::new(f),
        }
    }

    /// Make it not run drop.
    pub fn defuse(self) {
        core::mem::forget(self)
    }
}

impl<F: FnOnce()> Drop for OnDrop<F> {
    fn drop(&mut self) {
        unsafe { self.f.as_ptr().read()() }
    }
}