#systems #bevy #events #macro #fallible #plugin #error

yanked bevy_fallable_derive

Proc macro crate for bevy_fallable

0.3.2 Nov 28, 2020
0.3.1 Nov 28, 2020
0.3.0 Nov 28, 2020

#37 in #fallible


Used in bevy_fallable

MIT license

5KB
84 lines

bevy_fallible

Crates.io Docs.rs License

A simple plugin to install fallible systems to bevy

API

Library provides two main components: #[fallible_system] attribute macro and SystemErrorEvent struct. Essentially, every fallible_system will generate a SystemErrorEvent event if it results in an error, and that's about it.

For simplier usage, there is fallibleSystemPlugin to register everything you'll need to recieve error events.

Example

// Some system that might fail
#[fallible_system]
fn system(asset_server: Res<AssetServer>) -> anyhow::Result<()> {
    let handle: Handle<Texture> = asset_server.load("texture")?;
}

// Let's make another system to read every event about other
// systems failures and report !
#[derive(Default)]
struct ReportSystemState{ reader: EventReader<SystemErrorEvent> }
fn report_system(mut state: Local<ReportSystemState>, mut events: ResMut<Events<SystemErrorEvent>>) {
    for event in state.reader.iter(&mut events) {
        println!("Error in {}: {}", event.system_name, event.error); 
    }
}

fn main() {
    App::build()
        .add_plugin(fallibleSystemPlugin)
        .add_startup_system(system.system())
        .add_system(report_system.system())
        .run();
}

Dependencies

~1.5MB
~36K SLoC