Struct Permits

pub struct Permits { /* private fields */ }

Implementations

impl Permits

pub fn new(limit: usize) -> Self

Make a new set of permits with limit maximum concurrent permits available.

pub fn limit(&self) -> usize

Returns the maximum number of permits allowed.

pub fn get(&self) -> Option<Permit>

Attempts to get a permit. Returns None if there are no permits available.

pub fn get_revokable( &self, revoked_fn: impl FnOnce() -> Permit + 'static + Send, ) -> Option<Permit>

Attempts to get a permit that is revokable. Revokable permits can be revoked at any time after this function returns and must return the Permit when asked. revoked_fn will be called to retrieve the permit when it is revoked.

pub fn take(&self) -> Option<Permit>

Attempts to get a permit. If a permit isn’t available, but one can be revoked, one will be revoked to return a permit. Revoked permits are returned here before reservations are filled.

pub fn seize(&self) -> Vec<Permit>

Attempts to reserve all permits, including revoking any permits to do so. Permits that are seized are prioritized over any reservations.

pub fn reserve(&self) -> Reservation

Reserve a spot in line to receive a permit once one becomes available. Returns a future that resolves to a permit Reservations are first-come-first-serve, but permits that are revoked ignore reservations.

pub fn reserve_revokable( &self, revoked_fn: impl FnOnce() -> Permit + 'static + Send, ) -> Reservation

Reserve a spot in line to receive a permit once one becomes available. Returns a future that resovles to a revokable permit. Once the permit has been returned from the Reservation, it can be revoked at any time afterwards.

Trait Implementations

impl Clone for Permits

fn clone(&self) -> Permits

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Permits

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

Formats the value using the given formatter.