Trait Installer

Source

pub trait Installer {
    type Poller;

    // Required method
    fn install(self, world: &mut WorldBuilder) -> Self::Poller;
}

Expand description

Install-time trait for event sources.

An installer registers its resources into WorldBuilder and returns a concrete poller. The poller is a thin struct of pre-resolved ResourceIds — it knows how to reach into World but owns nothing.

Each poller defines its own poll() signature. This is intentional: different drivers need different parameters (e.g. a timer driver needs Instant, an IO driver does not).

§Examples

struct IoInstaller { capacity: usize }

struct IoPoller {
    poller_id: ResourceId,
    events_id: ResourceId,
}

impl Installer for IoInstaller {
    type Poller = IoPoller;

    fn install(self, world: &mut WorldBuilder) -> IoPoller {
        let poller_id = world.register(Poller::new());
        let events_id = world.register(MioEvents::with_capacity(self.capacity));
        IoPoller { poller_id, events_id }
    }
}

// Poller has its own poll signature — NOT a trait method.
impl IoPoller {
    fn poll(&mut self, world: &mut World) {
        // get resources via pre-resolved IDs, poll mio, dispatch
    }
}

let mut wb = WorldBuilder::new();
let io = wb.install_driver(IoInstaller { capacity: 1024 });
let mut world = wb.build();

loop {
    io.poll(&mut world);
}