Struct Lease

pub struct Lease<T> { /* private fields */ }

A handle to a leasable value.

Use poll_acquire to acquire the lease, take to grab the leased value, and restore to return the leased value when you’re done with it.

The code will panic if you attempt to access the S behind a Lease through Deref or DerefMut without having acquired the lease through poll_acquire first, or if you have called take.

The code will also panic if you attempt to drop a Lease without first restoring the leased value.

Implementations

impl<T> Lease<T>

pub fn poll_acquire(&mut self) -> Async<()>

Try to acquire the lease.

If the lease is not available, the current task is notified once it is.

pub fn release(&mut self)

Release the lease (if it has been acquired).

This provides a way of “undoing” a call to poll_ready should you decide you don’t need the lease after all, or if you only needed access by reference.

This method will panic if you attempt to release the lease after you have called take.

pub fn transfer(&mut self) -> Self

Leave behind a non-acquired lease in place of this one, and return this acquired lease.

This allows you to move a previously acquired lease into another context (like a Future) where you will later restore the leased value.

This method will panic if you attempt to call it without first having acquired the lease.

pub fn take(&mut self) -> T

Take the leased value.

This method will panic if you attempt to call it without first having acquired the lease.

Note that you must call restore on this lease before you drop it to return the leased value to other waiting clients. If you do not, dropping the lease will panic.

pub fn restore(&mut self, state: T)

Restore the leased value.

This method will panic if you attempt to call it without first having acquired the lease.

Note that once you return the leased value, the lease is no longer considered acquired.

Trait Implementations

impl<T> Clone for Lease<T>

fn clone(&self) -> Self

Returns a copy of the value.

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

Performs copy-assignment from source.

impl<T: Debug> Debug for Lease<T>

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

Formats the value using the given formatter.

impl<T> Default for Lease<T>

where T: Default,

fn default() -> Self

Returns the “default value” for a type.

impl<T> Deref for Lease<T>

type Target = T

The resulting type after dereferencing.

fn deref(&self) -> &Self::Target

Dereferences the value.

impl<T> DerefMut for Lease<T>

fn deref_mut(&mut self) -> &mut Self::Target

Mutably dereferences the value.

impl<T> Drop for Lease<T>

fn drop(&mut self)

Executes the destructor for this type.

impl<T> From<T> for Lease<T>

fn from(s: T) -> Self

Converts to this type from the input type.

impl<T> Send for Lease<T>

where T: Send,