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

euv_core/reactive/signal/
struct.rs
