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Listener

ferro_rs

Trait Listener 

Source 
pub trait Listener<E>:
    Send
    + Sync
    + 'static
where
    E: Event,
{
    // Required method
    fn handle<'life0, 'life1, 'async_trait>(
        &'life0 self,
        event: &'life1 E,
    ) -> Pin<Box<dyn Future<Output = Result<(), Error>> + Send + 'async_trait>>
       where 'life0: 'async_trait,
             'life1: 'async_trait,
             Self: 'async_trait;

    // Provided methods
    fn name(&self) -> &'static str { ... }
    fn should_stop_propagation(&self) -> bool { ... }
}
Expand description

A listener that handles events of type E.

Listeners contain the logic that should run when an event is dispatched. They can be synchronous or asynchronous.

§Example

use ferro_events::{Event, Listener, Error, async_trait};

#[derive(Clone)]
struct UserRegistered { email: String }

impl Event for UserRegistered {
    fn name(&self) -> &'static str { "UserRegistered" }
}

struct SendWelcomeEmail;

#[async_trait]
impl Listener<UserRegistered> for SendWelcomeEmail {
    async fn handle(&self, event: &UserRegistered) -> Result<(), Error> {
        println!("Welcome, {}!", event.email);
        Ok(())
    }
}

Required Methods§

Source

fn handle<'life0, 'life1, 'async_trait>( &'life0 self, event: &'life1 E, ) -> Pin<Box<dyn Future<Output = Result<(), Error>> + Send + 'async_trait>>
where 'life0: 'async_trait, 'life1: 'async_trait, Self: 'async_trait,

Handle the event.

This method is called when the event is dispatched. It receives an immutable reference to the event data.

Provided Methods§

Source

fn name(&self) -> &'static str

Returns the name of the listener for logging and debugging.

Source

fn should_stop_propagation(&self) -> bool

Whether this listener should stop propagation to other listeners.

If this returns true after handling, no further listeners will be called for this event.

Dyn Compatibility§

This trait is dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety".

Implementors§