Struct Lazy

pub struct Lazy<T, F = Pin<Box<dyn Future<Output = T> + Send>>> { /* private fields */ }

Lazy cell which is only instantiated upon first retreival of contained value

Implementations

impl<T> Lazy<T, Pin<Box<dyn Future<Output = T> + Send>>>

pub fn new(f: impl Future<Output = T> + 'static + Send) -> Self

Creates a new Lazy with the given instantiator.

Example

let lazy = Lazy::new(async {
    0 // Expensive calculation    
});
assert_eq!(lazy.get().await, &0);

impl<T> Lazy<T, Pin<Box<dyn Future<Output = T> + Send>>>

pub async fn get(&self) -> &T

Retreives the contents of the Lazy. If not instantiated, the instantiator block will be executed first.

Trait Implementations

impl<T: Debug, F> Debug for Lazy<T, F>

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

Formats the value using the given formatter.