Struct FlowLocal

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

A key for flow-local data stored in the execution context.

This type is generated by the flow_local! macro and performs very similarly to the thread_local! macro and std::thread::FlowLocal types. Data associated with a FlowLocal<T> is stored inside the current execution context and the data is destroyed when the execution context is destroyed.

Flow-local data can migrate between threads and hence requires a Send bound. Additionally, flow-local data also requires the 'static bound to ensure it lives long enough. When a key is accessed for the first time the flow’s data is initialized with the provided initialization expression to the macro.

Implementations

impl<T: Send + 'static> FlowLocal<T>

pub fn get(&self) -> FlowBox<T>

Access this flow-local.

This function will access this flow-local key to retrieve the data associated with the current flow and this key. If this is the first time this key has been accessed on this flow, then the key will be initialized with the initialization expression provided at the time the flow_local! macro was called.

Examples found in repository

examples/basic.rs (line 11)

fn main() {
    println!("the current locale is {}", LOCALE.get());
    LOCALE.set("de_DE".into());
    println!("changing locale to {}", LOCALE.get());

    let ec = ExecutionContext::capture();
    thread::spawn(move || {
        ec.run(|| {
            println!("the locale in the child thread is {}", LOCALE.get());
            LOCALE.set("fr_FR".into());
            println!("the new locale in the child thread is {}", LOCALE.get());
        });
    }).join().unwrap();

    println!("the locale of the parent thread is again {}", LOCALE.get());
}

pub fn set(&self, value: T)

Sets a new value for the flow-local.

Examples found in repository

examples/basic.rs (line 12)

fn main() {
    println!("the current locale is {}", LOCALE.get());
    LOCALE.set("de_DE".into());
    println!("changing locale to {}", LOCALE.get());

    let ec = ExecutionContext::capture();
    thread::spawn(move || {
        ec.run(|| {
            println!("the locale in the child thread is {}", LOCALE.get());
            LOCALE.set("fr_FR".into());
            println!("the new locale in the child thread is {}", LOCALE.get());
        });
    }).join().unwrap();

    println!("the locale of the parent thread is again {}", LOCALE.get());
}

Trait Implementations

impl<T> Debug for FlowLocal<T>

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

Formats the value using the given formatter.