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

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

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.

Examples
#[macro_use]
extern crate scoped_tls;

scoped_thread_local!(static FOO: u32);

FOO.set(&100, || {
    let val = FOO.with(|v| *v);
    assert_eq!(val, 100);

    // set can be called recursively
    FOO.set(&101, || {
        // ...
    });

    // Recursive calls restore the previous value.
    let val = FOO.with(|v| *v);
    assert_eq!(val, 100);
});

Gets a value out of this scoped variable.

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

Panics

This function will panic if set has not previously been called.

Examples
#[macro_use]
extern crate scoped_tls;

scoped_thread_local!(static FOO: u32);

FOO.with(|slot| {
    // work with `slot`
});

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

Trait Implementations

Auto Trait Implementations

Blanket Implementations

Gets the TypeId of self. Read more

Immutably borrows from an owned value. Read more

Mutably borrows from an owned value. Read more

Returns the argument unchanged.

Calls U::from(self).

That is, this conversion is whatever the implementation of From<T> for U chooses to do.

The type returned in the event of a conversion error.

Performs the conversion.

The type returned in the event of a conversion error.

Performs the conversion.