35 lines
875 B
Rust
35 lines
875 B
Rust
use gpui::{App, Application, Context, Entity, EventEmitter, prelude::*};
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struct Counter {
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count: usize,
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}
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struct Change {
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increment: usize,
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}
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impl EventEmitter<Change> for Counter {}
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fn main() {
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Application::new().run(|cx: &mut App| {
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let counter: Entity<Counter> = cx.new(|_cx| Counter { count: 0 });
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let subscriber = cx.new(|cx: &mut Context<Counter>| {
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cx.subscribe(&counter, |subscriber, _emitter, event, _cx| {
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subscriber.count += event.increment * 2;
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})
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.detach();
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Counter {
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count: counter.read(cx).count * 2,
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}
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});
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counter.update(cx, |counter, cx| {
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counter.count += 2;
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cx.notify();
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cx.emit(Change { increment: 2 });
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});
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assert_eq!(subscriber.read(cx).count, 4);
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});
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}
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