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SemaphoreState

Struct SemaphoreState 

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pub struct SemaphoreState { /* private fields */ }
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Shared admission-control counter backing SEMAPHORE words. Clones share the backend, so every word naming one semaphore observes the same count. Lock-free atomics throughout: no mutex exists to poison, so Drop paths stay infallible on every path including unwinding. No waiter ever sleeps on the counter, so the non-blocking acquire adds zero wedge surface.

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impl SemaphoreState

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pub fn try_acquire(&self) -> bool

Non-blocking acquire: true and counted when a permit was free. Compare-and-swap loop, so only a winning CAS claims a slot.

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pub fn release(&self)

Release one permit. Saturating and infallible: exactly-once last-drop release (see PermitInner) keeps this exact, and the floor (never a wrap, never a panic) is the backstop.

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pub fn available(&self) -> usize

Permits currently free. Exact at read time, stale the instant the caller acts on it: observability only, never admission input.

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impl Debug for SemaphoreState

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fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter. Read more

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impl<T> Any for T
where T: 'static + ?Sized,

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fn type_id(&self) -> TypeId

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where T: ?Sized,

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fn borrow(&self) -> &T

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impl<T> BorrowMut<T> for T
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fn borrow_mut(&mut self) -> &mut T

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impl<T> From<T> for T

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fn from(t: T) -> T

Returns the argument unchanged.

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impl<T> Instrument for T

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type Error = !

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Performs the conversion.
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type Error = <U as TryFrom<T>>::Error

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