Struct ScopedKey

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

Type representing a thread local storage key corresponding to a reference to the type parameter T.

Keys are statically allocated and can contain a reference to an instance of type T scoped to a particular lifetime. Keys provides two methods, set and with, both of which currently use closures to control the scope of their contents.

Implementations

impl<T> ScopedKey<T>

pub fn set<F, R>(&'static self, t: &T, f: F) -> R

where F: FnOnce() -> R,

Inserts a value into this scoped thread local storage slot for a duration of a closure.

While cb is running, the value t will be returned by get unless this function is called recursively inside of cb.

Upon return, this function will restore the previous value, if any was available.

pub fn with<F, R>(&'static self, f: F) -> R

where F: FnOnce(&T) -> R,

Gets a value out of this scoped variable.

This function takes a closure which receives the value of this variable.

pub fn try_with<F, R>(&'static self, f: F) -> R

where F: FnOnce(Option<&T>) -> R,

Gets a value out of this scoped variable.

pub fn is_set(&'static self) -> bool

Test whether this TLS key has been set for the current thread.

Trait Implementations

impl<T> Sync for ScopedKey<T>