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//! # Signals
//!
//! [Signals](dioxus::prelude::Signal) are a state management solution built-in into Dioxus.
//!
//! They allow us to store values so that components can **read and subscribe** to any change done to the stored value.
//!
//! Signals can even be read and mutated from multiple components.
//!
//! They are usually created by using the [`use_signal`](dioxus::prelude::use_signal) hook.
//!
//! ### Example
//!
//! ```rust
//! # use freya::prelude::*;
//! fn app() -> Element {
//! // The closure passed to `use_signal` will be called only
//! // the first time this component renders,
//! // it will return the initial value for the Signal.
//! // This closure is to prevent having to create the initial value
//! // every time the component runs again, as it is only needed the first time.
//! let mut count = use_signal(|| 0);
//!
//! let onclick = move |_| {
//! count += 1; // Shorthand for count.write() += 1;
//! // The moment the signal is mutated, it will notify
//! // all the components that have a read subscription
//! // to this signal (in this case, only `app`)
//! // that there has been a change.
//! // When that happens these components will render again
//! // so that an updated UI is produced and ultimately presented to the user.
//! };
//!
//! rsx!(
//! label {
//! onclick,
//! "{count}"
//! // By embedding the `count` signal in here, we are effectively
//! // creating a read subscription. It is the same as if was doing `"{count.read()}"`.
//! }
//! )
//! }
//! ```
//!
//! #### You can now learn about [Global Signals](crate::_docs::state_management::global_signals).