pub fn init_time_source(ts: Rc<dyn TimeSource>)Expand description
Set the platform time source used for time-budget accounting.
If no TimeSource is registered the executor runs every flush to
completion without yielding, which is acceptable for short-running
workloads but may cause frame drops in the browser.
Examples found in repository?
examples/counter.rs (line 40)
37fn main() {
38 // One-time executor setup.
39 init_flush_scheduler(Rc::new(CliScheduler));
40 init_time_source(Rc::new(CliClock::new()));
41
42 // ---- Signal basics ----
43 println!("=== Signal basics ===");
44 let count = Signal::new(0);
45 println!("count = {}", count.read());
46 count.set(42);
47 println!("count = {}", count.read());
48
49 // ---- Memo (auto-tracking computed value) ----
50 println!("\n=== Memo ===");
51 let a = Signal::new(2);
52 let b = Signal::new(3);
53 let a2 = a.clone();
54 let b2 = b.clone();
55 let sum = Memo::new(move || a2.read() + b2.read());
56 println!("2 + 3 = {}", sum.read());
57 a.set(10);
58 println!("10 + 3 = {}", sum.read());
59
60 // ---- TaskScope: spawn a task that watches a signal ----
61 println!("\n=== TaskScope (scoped signal watcher) ===");
62 let messages = Signal::new(vec!["hello".to_string()]);
63
64 {
65 let scope = TaskScope::new();
66 let msgs = messages.clone();
67 scope.spawn(async move {
68 loop {
69 let val = msgs.changed().await;
70 println!(" task observed: {:?}", val);
71 }
72 });
73
74 messages.set(vec!["hello".to_string(), "world".to_string()]);
75 messages.set(vec![
76 "hello".to_string(),
77 "world".to_string(),
78 "!".to_string(),
79 ]);
80
81 // Explicit drop — cancels the task and cleans up resources.
82 drop(scope);
83 }
84 println!("(scope dropped — task and subscriptions cleaned up)");
85
86 // ---- Batch: multiple sets, one notification ----
87 println!("\n=== Batch ===");
88 let x = Signal::new(0);
89 let notifications = Rc::new(Cell::new(0u32));
90 let n = Rc::clone(¬ifications);
91 let x2 = x.clone();
92
93 let scope = TaskScope::new();
94 scope.spawn(async move {
95 loop {
96 x2.changed().await;
97 n.set(n.get() + 1);
98 }
99 });
100
101 batch(|| {
102 x.set(1);
103 x.set(2);
104 x.set(3);
105 });
106 println!(
107 "After 3 sets in a batch: {} notification(s)",
108 notifications.get()
109 );
110 // Should be 1 — not 3.
111
112 println!("\nDone.");
113}