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}
32
33/// A reactive signal handle.
34///
35/// Allows reading, writing, and subscribing to changes.
36/// Implements `Clone` and `Copy` for ergonomic use; all copies share the same
37/// underlying state. The inner state is heap-allocated via `Rc<RefCell<>>` and
38/// tracked in a global registry to prevent premature deallocation. The `Copy`
39/// semantics are safe because only the pointer address is copied — the actual
40/// `Rc` reference is held by the registry for the lifetime of the program.
41#[derive(CustomDebug, Data, Default, Eq, New, PartialEq)]
42pub struct Signal<T>
43where
44    T: Clone + PartialEq + 'static,
45{
46    /// Address of the heap-allocated inner state.
47    #[debug(skip)]
48    #[get(pub(crate), type(copy))]
49    #[get_mut(pub(crate))]
50    #[set(pub(crate))]
51    pub(crate) inner: usize,
52    /// Marker for the generic type parameter (uses fn pointer to be `Copy`
53    /// regardless of `T`).
54    #[debug(skip)]
55    #[get(pub(crate), type(copy))]
56    #[get_mut(pub(crate))]
57    #[set(pub(crate))]
58    pub(crate) _marker: std::marker::PhantomData<fn() -> T>,
59}
60
61/// A `Sync` wrapper for single-threaded global `Signal` access.
62///
63/// SAFETY: This type is only safe to use in single-threaded contexts
64/// (e.g., WASM). It implements `Sync` to allow usage as a `static`
65/// variable, but concurrent access from multiple threads would be
66/// undefined behavior.
67#[derive(CustomDebug, Data, New)]
68pub struct SignalCell<T>
69where
70    T: Clone + PartialEq + 'static,
71{
72    /// Interior-mutable storage for an optional signal handle.
73    #[debug(skip)]
74    #[get(pub(crate))]
75    #[get_mut(pub(crate))]
76    #[set(pub(crate))]
77    pub(crate) inner: UnsafeCell<Option<Signal<T>>>,
78}
79
80/// A `Sync` wrapper for single-threaded global `HashMap` access.
81///
82/// SAFETY: This type is only safe to use in single-threaded contexts
83/// (e.g., WASM). It implements `Sync` to allow usage as a `static mut`
84/// variable, but concurrent access from multiple threads would be
85/// undefined behavior.
86#[derive(Data, Debug, New)]
87pub(crate) struct SignalInnerRegistryCell(
88    /// Interior-mutable storage for the signal inner registry.
89    #[get(pub(crate))]
90    #[get_mut(pub(crate))]
91    #[set(pub(crate))]
92    pub(crate) UnsafeCell<Option<HashMap<usize, Rc<dyn Any>>>>,
93);
euv_core/reactive/signal/struct.rs

euv_core/reactive/signal/
struct.rs
