euv_core/reactive/signal/
struct.rs

1use crate::*;
2
3/// Inner state of a signal, holding the value and subscribed listeners.
4///
5/// This struct is not exposed directly; use `Signal` instead.
6#[derive(CustomDebug, Data, New)]
7pub(crate) struct SignalInner<T>
8where
9    T: Clone,
10{
11    /// The current value of the signal.
12    #[debug(skip)]
13    #[get(pub(crate))]
14    #[get_mut(pub(crate))]
15    #[set(pub(crate))]
16    pub(crate) value: T,
17    /// Callbacks to invoke when the value changes.
18    #[debug(skip)]
19    #[get(pub(crate))]
20    #[get_mut(pub(crate))]
21    #[set(pub(crate))]
22    pub(crate) listeners: Vec<Box<dyn FnMut()>>,
23    /// Whether this signal is still active. Set to `false` by `clear_listeners()`
24    /// to make subsequent `set()` calls complete no-ops (no value update, no
25    /// listener invocation, no `schedule_signal_update()`), ensuring stale
26    /// closures like orphaned `setInterval` handlers become harmless.
27    #[get(pub(crate), type(copy))]
28    #[get_mut(pub(crate))]
29    #[set(pub(crate))]
30    pub(crate) alive: bool,
31    /// IDs of dynamic nodes that depend on this signal for precise dirty marking.
32    /// When this signal changes, only these dynamic nodes are marked dirty
33    /// instead of broadcasting to all registered dynamic nodes.
34    #[debug(skip)]
35    #[get(pub(crate))]
36    #[get_mut(pub(crate))]
37    #[set(pub(crate))]
38    #[new(skip)]
39    pub(crate) dependents: Vec<usize>,
40}
41
42/// A reactive signal handle.
43///
44/// Allows reading, writing, and subscribing to changes.
45/// Implements `Clone` and `Copy` for ergonomic use; all copies share the same
46/// underlying state. The inner state is heap-allocated via `Rc<RefCell<>>` and
47/// tracked in a global registry to prevent premature deallocation. The `Copy`
48/// semantics are safe because only the pointer address is copied — the actual
49/// `Rc` reference is held by the registry for the lifetime of the program.
50#[derive(CustomDebug, Data, Default, Eq, New, PartialEq)]
51pub struct Signal<T>
52where
53    T: Clone + PartialEq + 'static,
54{
55    /// Address of the heap-allocated inner state.
56    #[debug(skip)]
57    #[get(pub(crate), type(copy))]
58    #[get_mut(pub(crate))]
59    #[set(pub(crate))]
60    pub(crate) inner: usize,
61    /// Marker for the generic type parameter (uses fn pointer to be `Copy`
62    /// regardless of `T`).
63    #[debug(skip)]
64    #[get(pub(crate), type(copy))]
65    #[get_mut(pub(crate))]
66    #[set(pub(crate))]
67    pub(crate) _marker: std::marker::PhantomData<fn() -> T>,
68}
69
70/// A `Sync` wrapper for single-threaded global `Signal` access.
71///
72/// SAFETY: This type is only safe to use in single-threaded contexts
73/// (e.g., WASM). It implements `Sync` to allow usage as a `static`
74/// variable, but concurrent access from multiple threads would be
75/// undefined behavior.
76#[derive(CustomDebug, Data, New)]
77pub struct SignalCell<T>
78where
79    T: Clone + PartialEq + 'static,
80{
81    /// Interior-mutable storage for an optional signal handle.
82    #[debug(skip)]
83    #[get(pub(crate))]
84    #[get_mut(pub(crate))]
85    #[set(pub(crate))]
86    pub(crate) inner: UnsafeCell<Option<Signal<T>>>,
87}
88
89/// A `Sync` wrapper for single-threaded global `HashMap` access.
90///
91/// SAFETY: This type is only safe to use in single-threaded contexts
92/// (e.g., WASM). It implements `Sync` to allow usage as a `static mut`
93/// variable, but concurrent access from multiple threads would be
94/// undefined behavior.
95#[derive(Data, Debug, New)]
96pub(crate) struct SignalInnerRegistryCell(
97    /// Interior-mutable storage for the signal inner registry.
98    #[get(pub(crate))]
99    #[get_mut(pub(crate))]
100    #[set(pub(crate))]
101    pub(crate) UnsafeCell<Option<HashMap<usize, Rc<dyn Any>>>>,
102);
euv_core/reactive/signal/struct.rs

euv_core/reactive/signal/
struct.rs
