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use ecs::error::Error;
use ecs::event::component::{Changed, EventMatchExt};
use ecs::pair::Pair;
use ecs::phase::UPDATE;
use ecs::query::Query;
use ecs::system::observer::Observe;
use ecs::{Component, World, error};
use tracing::level_filters::LevelFilter;
use tracing_subscriber::EnvFilter;
use tracing_subscriber::fmt::time::ChronoLocal;
use tracing_subscriber::layer::SubscriberExt;
use tracing_subscriber::util::SubscriberInitExt;
#[derive(Component)]
struct State
{
value: u32,
}
fn do_something_fallible(query: Query<(&mut State,)>) -> Result<(), Error>
{
for (mut state,) in &query {
state.value += 1;
state.set_changed();
if state.value > 3 {
return Err(error!("Invalid state value {}", state.value));
}
}
Ok(())
}
fn handle_state_changed(observe: Observe<Pair<Changed, State>>) -> Result<(), Error>
{
for evt_match in &observe {
let state = evt_match.get_ent_target_comp();
if state.value > 3 {
return Err(error!("Invalid state value {}", state.value));
}
tracing::info!("State has valid value {}", state.value);
}
Ok(())
}
fn main()
{
tracing_subscriber::registry()
.with(
tracing_subscriber::fmt::layer()
.with_timer(ChronoLocal::new("%T%.6f".to_string())),
)
.with(
EnvFilter::builder()
.with_default_directive(LevelFilter::DEBUG.into())
.from_env()
.unwrap(),
)
.init();
let mut world = World::new();
world.set_err_handler(ecs::error::err_handler_log_error);
world.create_entity((State { value: 0 },));
world.register_system(*UPDATE, do_something_fallible);
world.register_observer(handle_state_changed);
world.step();
world.step();
world.step();
world.step();
}
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